162 results on '"Yiannoutsos CT"'
Search Results
2. Cerebrospinal fluid neopterin decay characteristics after initiation of antiretroviral therapy
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Yilmaz, A, Yiannoutsos, CT, Fuchs, D, Price, RW, Crozier, K, Hagberg, L, Spudich, S, and Gisslén, M
- Abstract
Background: Neopterin, a biomarker of macrophage activation, is elevated in the cerebrospinal fluid (CSF) of most HIV-infected individuals and decreases after initiation of antiretroviral therapy (ART). We studied decay characteristics of neopterin in CSF and blood after commencement of ART in HIV-infected subjects and estimated the set-point levels of CSF neopterin after ART-mediated viral suppression.Methods: CSF and blood neopterin were longitudinally measured in 102 neurologically asymptomatic HIV-infected subjects who were treatment-naïve or had been off ART for ≥ 6 months. We used a non-linear model to estimate neopterin decay in response to ART and a stable neopterin set-point attained after prolonged ART. Seven subjects with HIV-associated dementia (HAD) who initiated ART were studied for comparison.Results: Non-HAD patients were followed for a median 84.7 months. Though CSF neopterin concentrations decreased rapidly after ART initiation, it was estimated that set-point levels would be below normal CSF neopterin levels (
- Published
- 2013
3. Risk factors for death in HIV-infected adult african patients recieving anti-retroviral therapy
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Sika, AM, Wools-Kaloustian, K, Mwangi, AW, Kimaiyo, SN, Diero, LO, Ayuo, PO, Owino-Ong'or, WD, Sidle, JE, Einterz, RM, Yiannoutsos, CT, Musick, B, and Tierney, WN
- Abstract
Objective: To determine risk factors for death in HIV-infected African patients on anti-retroviral therapy (ART).Design: Retrospective Case-control study.Setting: The MOH-USAID-AMPATH Partnership ambulatory HIV-care clinics in western Kenya.Results: Between November 2001 and December 2005 demographic, clinical and laboratory data from 527 deceased and 1054 living patients receiving ART were compared to determine independent risk factors for death. Median age at ART initiation was 38 versus 36 years for the deceased and living patients respectively (p100/mm3 (HR=1.553. 95% CI (1.156, 2.087), p
- Published
- 2012
4. Sampling-Based Approaches to Improve Estimation of Mortality among Patient Dropouts: Experience from a Large PEPFAR-Funded Program in Western Kenya
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Spire B, Murray Sa, Ongolo-Zogo P, Morris L, Mahendra Vs, Grant E, Martin Jn, Kimaiyo S, Marcellin F, Cheng N, Moatti Jp, Carrieri Mp, Solomon S, Logie D, Tobi P, Montaner Js, Schmidt E, Wools-Kaloustian K, Mayer Kh, Kantor R, Bacon Mc, Daly C, Andia I, Ochieng, Venkatesh Kk, Guzman D, Gorman D, Merico F, Pepper L, Maier M, An Mw, Kumarasamy N, Phillips P, George G, Verma P, Hull Mw, Emenyonu N, Levin L, Braitstein P, Hogg Rs, Abe C, Ochieng D, Cecelia Aj, Bangsberg Dr, Kaida A, Pillay C, Abega Sc, Dia A, Buckton Aj, Pillay, Frangakis Ce, Brown L, Musick Bs, Koulla-Shiro S, Protopopescu C, Masura M, Boyer S, Renton A, Venter F, and Yiannoutsos Ct
- Subjects
Adult ,Male ,Program evaluation ,Patient Dropouts ,Anti-HIV Agents ,Population ,Public Health and Epidemiology ,lcsh:Medicine ,Public Health and Epidemiology/Infectious Diseases ,HIV Infections ,Public Health and Epidemiology/Health Policy ,03 medical and health sciences ,0302 clinical medicine ,Quality of life (healthcare) ,Acquired immunodeficiency syndrome (AIDS) ,Nursing ,Infectious Diseases/Viral Infections ,Infectious Diseases/Sexually Transmitted Diseases ,medicine ,Humans ,030212 general & internal medicine ,lcsh:Science ,education ,Selection Bias ,Reproductive health ,0303 health sciences ,education.field_of_study ,Multidisciplinary ,030306 microbiology ,business.industry ,lcsh:R ,Youth leaders ,Infectious Diseases/HIV Infection and AIDS ,medicine.disease ,Kenya ,Focus group ,Infectious Diseases ,lcsh:Q ,Female ,Mathematics/Statistics ,business ,Program Evaluation ,Research Article ,Qualitative research - Abstract
Background Monitoring and evaluation (M&E) of HIV care and treatment programs is impacted by losses to follow-up (LTFU) in the patient population. The severity of this effect is undeniable but its extent unknown. Tracing all lost patients addresses this but census methods are not feasible in programs involving rapid scale-up of HIV treatment in the developing world. Sampling-based approaches and statistical adjustment are the only scaleable methods permitting accurate estimation of M&E indices. Methodology/Principal Findings In a large antiretroviral therapy (ART) program in western Kenya, we assessed the impact of LTFU on estimating patient mortality among 8,977 adult clients of whom, 3,624 were LTFU. Overall, dropouts were more likely male (36.8% versus 33.7%; p = 0.003), and younger than non-dropouts (35.3 versus 35.7 years old; p = 0.020), with lower median CD4 count at enrollment (160 versus 189 cells/ml; p
- Published
- 2008
5. Selegiline and oxidative stress in HIV-associated cognitive impairment.
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Schifitto G, Yiannoutsos CT, Ernst T, Navia BA, Nath A, Sacktor N, Anderson C, Marra CM, Clifford DB, ACTG 5114 Team, Schifitto, G, Yiannoutsos, C T, Ernst, T, Navia, B A, Nath, A, Sacktor, N, Anderson, C, Marra, C M, and Clifford, D B
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- 2009
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6. Designs for clinical trials to test the efficacy of therapeutics in progressive multifocal leukoencephalopathy RID G-8810-2011
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Yiannoutsos, Ct and Andrea De Luca
7. Stereotactic body radiation therapy for early-stage non-small-cell lung carcinoma: four-year results of a prospective phase II study.
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Fakiris AJ, McGarry RC, Yiannoutsos CT, Papiez L, Williams M, Henderson MA, and Timmerman R
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- 2009
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8. A pilot trial of serial 18F-fluorodeoxyglucose positron emission tomography in patients with medically inoperable stage I non-small-cell lung cancer treated with hypofractionated stereotactic body radiotherapy.
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Henderson MA, Hoopes DJ, Fletcher JW, Lin PF, Tann M, Yiannoutsos CT, Williams MD, Fakiris AJ, McGarry RC, Timmerman RD, Henderson, Mark A, Hoopes, David J, Fletcher, James W, Lin, Pei-Fen, Tann, Mark, Yiannoutsos, Constantin T, Williams, Mark D, Fakiris, Achilles J, McGarry, Ronald C, and Timmerman, Robert D
- Abstract
Purpose: Routine assessment was made of tumor metabolic activity as measured by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in Stage I non-small-cell lung cancer (NSCLC). This report describes PET correlates prospectively collected after stereotactic body radiotherapy (SBRT) for patients with medically inoperable NSCLC.Methods and Materials: 14 consecutive patients with medically inoperable Stage I NSCLC were enrolled. All patients received SBRT to 60-66 Gy in three fractions. Patients underwent serial planned FDG-PET/computed tomography fusion imaging before SBRT and at 2, 26, and 52 weeks after SBRT.Results: With median follow-up of 30.2 months, no patients experienced local failure. One patient developed regional failure, 1 developed distant failure, and 1 developed a second primary. The median tumor maximum standardized uptake value (SUV(max)) before SBRT was 8.70. The median SUV(max) values at 2, 26, and 52 weeks after SBRT were 6.04, 2.80, and 3.58, respectively. Patients with low pre-SBRT SUV were more likely to experience initial 2-week rises in SUV, whereas patients with high pre-SBRT SUV commonly had SUV declines 2 weeks after treatment (p = 0.036). Six of 13 patients had primary tumor SUV(max) >3.5 at 12 months after SBRT but remained without evidence of local disease failure on further follow-up.Conclusions: A substantial proportion of patients may have moderately elevated FDG-PET SUV(max) at 12 months without evidence of local failure on further follow-up. Thus, slightly elevated PET SUV(max) should not be considered a surrogate for local treatment failure. Our data do not support routine serial FDG-PET/computed tomography for follow-up of patients receiving SBRT for Stage I NSCLC. [ABSTRACT FROM AUTHOR]- Published
- 2010
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9. Correcting mortality estimates among children and youth on antiretroviral therapy in southern Africa: A comparative analysis between a multi-country tracing study and linkage to a health information exchange.
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Nyakato P, Schomaker M, Boulle A, Euvrard J, Wood R, Eley B, Prozesky H, Christ B, Anderegg N, Ayakaka I, Rafael I, Kunzekwenyika C, Moore CB, van Lettow M, Chimbetete C, Mbewe S, Ballif M, Egger M, Yiannoutsos CT, Cornell M, and Davies MA
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- Humans, Adolescent, Child, Young Adult, Africa, Southern epidemiology, Male, Female, Child, Preschool, Infant, Anti-HIV Agents therapeutic use, Adult, HIV Infections drug therapy, HIV Infections mortality, Lost to Follow-Up
- Abstract
Objectives: The objective of this study is to assess the outcomes of children, adolescents and young adults with HIV reported as lost to follow-up, correct mortality estimates for children, adolescents and young adults with HIV for unascertained outcomes in those loss to follow-up (LTFU) based on tracing and linkage data separately using data from the International epidemiology Databases to Evaluate AIDS in Southern Africa., Methods: We included data from two different populations of children, adolescents and young adults with HIV; (1) clinical data from children, adolescents and young adults with HIV aged ≤24 years from Lesotho, Malawi, Mozambique, Zambia and Zimbabwe; (2) clinical data from children, adolescents and young adults with HIV aged ≤14 years from the Western Cape (WC) in South Africa. Outcomes of patients lost to follow-up were available from (1) a tracing study and (2) linkage to a health information exchange. For both populations, we compared six methods for correcting mortality estimates for all children, adolescents and young adults with HIV., Results: We found substantial variations of mortality estimates among children, adolescents and young adults with HIV reported as lost to follow-up versus those retained in care. Ascertained mortality was higher among lost and traceable children, adolescents and young adults with HIV and lower among lost and linkable than those retained in care (mortality: 13.4% [traced] vs. 12.6% [retained-other Southern Africa countries]; 3.4% [linked] vs. 9.4% [retained-WC]). A high proportion of lost to follow-up children, adolescents and young adults with HIV had self-transferred (21.0% and 47.0%) in the traced and linked samples, respectively. The uncorrected method of non-informative censoring yielded the lowest mortality estimates among all methods for both tracing (6.0%) and linkage (4.0%) approaches at 2 years from ART start. Among corrected methods using ascertained data, multiple imputation, incorporating ascertained data (MI(asc.)) and inverse probability weighting with logistic weights were most robust for the tracing approach. In contrast, for the linkage approach, MI(asc.) was the most robust., Conclusions: Our findings emphasise that lost to follow-up is non-ignorable and both tracing and linkage improved outcome ascertainment: tracing identified substantial mortality in those reported as lost to follow-up, whereas linkage did not identify out-of-facility deaths, but showed that a large proportion of those reported as lost to follow-up were self-transfers., (© 2024 The Author(s). Tropical Medicine & International Health published by John Wiley & Sons Ltd.)
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- 2024
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10. Modeling the HIV Cascade of Care Using Routinely Collected Clinical Data to Guide Programmatic Interventions and Policy Decisions.
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Bakoyannis G, Elul B, Wools-Kaloustian KK, Brown S, Semeere A, Castelnuovo B, Diero L, Nakigozi G, Lyamuya R, and Yiannoutsos CT
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- Humans, Adult, Female, Male, Young Adult, Middle Aged, Adolescent, Anti-HIV Agents therapeutic use, Africa, Eastern epidemiology, Health Policy, HIV Infections drug therapy, Viral Load
- Abstract
Background: The HIV care cascade is a framework to examine effectiveness of HIV programs and progress toward global targets to end the epidemic but has been conceptualized as a unidirectional process that ignores cyclical care patterns. We present a dynamic cascade that accounts for patient "churn" and apply novel analytic techniques to readily available clinical data to robustly estimate program outcomes and efficiently assess progress toward global targets., Methods: Data were assessed for 35,649 people living with HIV and receiving care at 78 clinics in East Africa between 2014 and 2020. Patients were aged ≥15 years and had ≥1 viral load measurements. We used multi-state models to estimate the probability of being in 1 of 5 states of a dynamic HIV cascade: (1) in HIV care but not on antiretroviral therapy (ART), (2) on ART, (3) virally suppressed, (4) in a gap-in-care, and (5) deceased and compared these among subgroups. To assess progress toward global targets, we summed those probabilities across patients and generated population-level proportions of patients on ART and virally suppressed in mid-2020., Results: One year after enrollment, 2.8% of patients had not initiated ART, 86.7% were receiving ART, 57.4% were virally suppressed, 10.2% were disengaged from care, and 0.3% had died. At 5 years, the proportion on ART remained steady but viral suppression increased to 77.2%. Of those aged 15-25, >20% had disengaged from care and <60% were virally suppressed. In mid-2020, 90.1% of the cohort was on ART, 90.7% of whom had suppressed virus., Conclusions: Novel analytic approaches can characterize patient movement through a dynamic HIV cascade and, importantly, by capitalizing on readily available data from clinical cohorts, offer an efficient approach to estimate population-level proportions of patients on ART and virally suppressed. Significant progress toward global targets was observed in our cohort but challenges remain among younger patients., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)
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- 2024
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11. Self-transfers, Hospital Admissions and Mortality Among Children and Adolescents Lost to Follow-up From Antiretroviral Therapy Programs in the Western Cape, South Africa Between 2004 and 2019: Linkage to Provincial Records.
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Nyakato P, Boulle A, Wood R, Eley B, Rabie H, Egger M, Yiannoutsos CT, Davies MA, and Cornell M
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- Humans, Male, Child, Adolescent, South Africa epidemiology, Retrospective Studies, Lost to Follow-Up, Hospitalization, Hospitals, HIV Infections drug therapy, HIV Infections epidemiology, Anti-HIV Agents therapeutic use
- Abstract
Background: Pediatric programs face a high rate of loss to follow-up (LTFU) among children and adolescents living with HIV (CAHIV). We assessed true outcomes and predictors of these among CAHIV who were LTFU using linkage to the Western Cape Provincial Health Data Centre at Western Cape sites of the International epidemiology Databases to Evaluate AIDS-Southern Africa collaboration., Methods: We examined factors associated with self-transfer, hospital admission and mortality using competing risks regression in a retrospective cohort of CAHIV initiating antiretroviral therapy <15 years old between 2004 and 2019 and deemed LTFU (no recorded visit at the original facility for ≥180 days from the last visit date before database closure and not known to have officially transferred out or deceased)., Results: Of the 1720 CAHIV deemed LTFU, 802 (46.6%) had self-transferred and were receiving care elsewhere within the Western Cape, 463 (26.9%) had been hospitalized and 45 (2.6%) CAHIV had died. The overall rates of self-transfer, hospitalization, mortality and LTFU were 9.4 [95% confidence interval (CI): 8.8-10.1], 5.4 (95% CI: 5.0-6.0), 0.5 (95% CI: 0.4-0.7) and 4.8 (95% CI: 4.4-5.3) per 100 person-years respectively. Increasing duration on antiretroviral therapy before LTFU was associated with self-transfers while male sex, older age at last visit (≥10 years vs. younger) were associated with hospital admission and immune suppression at last visit was associated with 5 times higher mortality., Conclusions: Nearly half of CAHIV classified as LTFU had self-transferred to another health facility, a quarter had been hospitalized and a small proportion had died., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2024
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12. Characterizing participants who respond to text, email, phone calls, or postcards in a SARS-CoV-2 prevalence study.
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Duszynski TJ, Fadel W, Dixon B, Yiannoutsos CT, Halverson P, and Menachemi N
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- Humans, Male, Female, Cross-Sectional Studies, Adult, Middle Aged, Indiana epidemiology, Young Adult, Adolescent, Aged, SARS-CoV-2, Prevalence, Telephone, Electronic Mail statistics & numerical data, Text Messaging statistics & numerical data, Surveys and Questionnaires, COVID-19 Testing statistics & numerical data, Contact Tracing statistics & numerical data, Postal Service, Patient Selection, COVID-19 epidemiology
- Abstract
Introduction: Multiple modalities and frequencies of contact are needed to maximize recruitment in many public health surveys. The purpose of this analysis is to characterize respondents to a statewide SARS-CoV-2 testing study whose participation followed either postcard, phone outreach or electronic means of invitation. In addition, we examine how participant characteristics differ based upon the number of contacts needed to elicit participation., Methods: This is a cross-sectional analysis of survey data collected from participants who were randomly selected to represent Indiana residents and were invited to be tested for Covid-19 in April 2020. Participants received invitations via postcard, text/emails, and/or robocalls/texts based upon available contact information. The modality, and frequency of contacts, that prompted participation was determined by when the notification was sent and when the participant responded and subsequently registered to participate in the study. Chi square analyses were used to determine differences between groups and significant findings were analyzed using multinomial logistic regression., Results: Respondents included 3,658 individuals and were stratified by postcards (7.9%), text/emails (26.5%), and robocalls/text (65.7%) with 19.7% registering after 1 contact, 47.9% after 2 contacts, and 32.4% after 3 contacts encouraging participation. Females made up 54.6% of the sample and responded at a higher rate for postcards (8.2% vs. 7.5%) and text/emails (28.1 vs. 24.6%) as compared to males (χ
2 = 7.43, p = 0.025). Compared to males, females responded at a higher percentage after 1 contact (21.4 vs. 17.9%, χ2 = 7.6, p = 0.023). Those over 60 years responded most often after 2 contacts (χ2 = 27.5, p < 0.001) when compared to others at younger age groups. In regression analysis, participant sex (p = 0.036) age (p = 0.005), educational attainment (p = < 0.0001), and being motivated by "free testing" (p = 0.036) were correlated with participation in the prevalence study., Discussion: Researchers should be aware that the modality of contact as well as the number of prompts used could influence differential participation in public health studies. Our findings can inform researchers developing studies that rely on selective participation by study subjects. We explore how to increase participation within targeted demographic groups using specific modalities and examining frequency of contact., (© 2024. The Author(s).)- Published
- 2024
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13. Adaptation of the Client Diagnostic Questionnaire for East Africa.
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Kwobah EK, Goodrich S, Kulzer JL, Kanyesigye M, Obatsa S, Cheruiyot J, Kiprono L, Kibet C, Ochieng F, Bukusi EA, Ofner S, Brown SA, Yiannoutsos CT, Atwoli L, and Wools-Kaloustian K
- Abstract
Research increasingly involves cross-cultural work with non-English-speaking populations, necessitating translation and cultural validation of research tools. This paper describes the process of translating and criterion validation of the Client Diagnostic Questionnaire (CDQ) for use in a multisite study in Kenya and Uganda. The English CDQ was translated into Swahili, Dholuo (Kenya) and Runyankole/Rukiga (Uganda) by expert translators. The translated documents underwent face validation by a bilingual committee, who resolved unclear statements, agreed on final translations and reviewed back translations to English. A diagnostic interview by a mental health specialist was used for criterion validation, and Kappa statistics assessed the strength of agreement between non-specialist scores and mental health professionals' diagnoses. Achieving semantic equivalence between translations was a challenge. Validation analysis was done with 30 participants at each site (median age 32.3 years (IQR = (26.5, 36.3)); 58 (64.4%) female). The sensitivity was 86.7%, specificity 64.4%, positive predictive value 70.9% and negative predictive value 82.9%. Diagnostic accuracy by the non-specialist was 75.6%. Agreement was substantial for major depressive episode and positive alcohol (past 6 months) and alcohol abuse (past 30 days). Agreement was moderate for other depressive disorders, panic disorder and psychosis screen; fair for generalized anxiety, drug abuse (past 6 months) and Post Traumatic Stress Disorder (PTSD); and poor for drug abuse (past 30 days). Variability of agreement between sites was seen for drug use (past 6 months) and PTSD. Our study successfully adapted the CDQ for use among people living with HIV in East Africa. We established that trained non-specialists can use the CDQ to screen for common mental health and substance use disorders with reasonable accuracy. Its use has the potential to increase case identification, improve linkage to mental healthcare, and improve outcomes. We recommend further studies to establish the psychometric properties of the translated tool., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Kwobah et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)
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- 2024
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14. Mortality Among HIV-Infected Adults on Antiretroviral Therapy in Southern Uganda.
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Nabukalu D, Yiannoutsos CT, Semeere A, Musick BS, Murungi T, Namulindwa JV, Waswa F, Nakigozi G, Sewankambo NK, Reynolds SJ, Lutalo T, Makumbi F, Kigozi G, Nalugoda F, and Wools-Kaloustian K
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- Adult, Humans, Female, Male, Uganda epidemiology, Lost to Follow-Up, Anti-Retroviral Agents therapeutic use, HIV Infections drug therapy, Anti-HIV Agents therapeutic use
- Abstract
Background: Monitoring and evaluation of clinical programs requires assessing patient outcomes. Numerous challenges complicate these efforts, the most insidious of which is loss to follow-up (LTFU). LTFU is a composite outcome, including individuals out of care, undocumented transfers, and unreported deaths. Incorporation of vital status information from routine patient outreach may improve the mortality estimates for those LTFU., Settings: We analyzed routinely collected clinical and patient tracing data for individuals (15 years or older) initiating antiretroviral treatment between January 2014 and December 2018 at 2 public HIV care clinics in greater Rakai, Uganda., Methods: We derived unadjusted mortality estimates using Kaplan-Meier methods. Estimates, adjusted for unreported deaths, applied weighting through the Frangakis and Rubin method to represent outcomes among LTFU patients who were successfully traced and for whom vital status was ascertained. Confidence intervals were determined through bootstrap methods., Results: Of 1969 patients with median age at antiretroviral treatment initiation of 31 years (interquartile range: 25-38), 1126 (57.2%) were female patients and 808 (41%) were lost. Of the lost patients, 640 patient files (79.2%) were found and reviewed, of which 204 (31.8%) had a tracing attempt. Within the electronic health records of the program, 28 deaths were identified with an estimated unadjusted mortality 1 year after antiretroviral treatment initiation of 2.5% (95% CI: 1.8% to 3.3%). Using chart review and patient tracing data, an additional 24 deaths (total 52) were discovered with an adjusted 1-year mortality of 3.8% (95% CI: 2.6% to 5.0%)., Conclusions: Data from routine outreach efforts by HIV care and treatment programs can be used to support plausible adjustments to estimates of client mortality. Mortality estimates without active ascertainment of vital status of LTFU patients may significantly underestimate program mortality., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)
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- 2024
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15. Joint modeling of longitudinal and competing-risk data using cumulative incidence functions for the failure submodels accounting for potential failure cause misclassification through double sampling.
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Thomadakis C, Meligkotsidou L, Yiannoutsos CT, and Touloumi G
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- Humans, Incidence, Bayes Theorem, Proportional Hazards Models, Computer Simulation, Models, Statistical
- Abstract
Most of the literature on joint modeling of longitudinal and competing-risk data is based on cause-specific hazards, although modeling of the cumulative incidence function (CIF) is an easier and more direct approach to evaluate the prognosis of an event. We propose a flexible class of shared parameter models to jointly model a normally distributed marker over time and multiple causes of failure using CIFs for the survival submodels, with CIFs depending on the "true" marker value over time (i.e., removing the measurement error). The generalized odds rate transformation is applied, thus a proportional subdistribution hazards model is a special case. The requirement that the all-cause CIF should be bounded by 1 is formally considered. The proposed models are extended to account for potential failure cause misclassification, where the true failure causes are available in a small random sample of individuals. We also provide a multistate representation of the whole population by defining mutually exclusive states based on the marker values and the competing risks. Based solely on the assumed joint model, we derive fully Bayesian posterior samples for state occupation and transition probabilities. The proposed approach is evaluated in a simulation study and, as an illustration, it is fitted to real data from people with HIV., (© The Author 2022. Published by Oxford University Press.)
- Published
- 2023
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16. Preswitch Regimens Influence the Rate of Weight Gain After Switch to Tenofovir Disoproxil Fumarate, Lamivudine, and Dolutegravir (TLD): Study From an East African Cohort.
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Bourgi K, Ofner S, Musick B, Wools-Kaloustian K, Humphrey JM, Diero L, Yiannoutsos CT, and Gupta SK
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Background: Switching from non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimens to dolutegravir (DTG) has been associated with greater weight gain., Methods: We conducted our analysis using a longitudinal cohort of people with HIV (PWH) in Western Kenya. We evaluated changes in the rate of weight gain among treatment-experienced, virally suppressed PWH who switched from NNRTI to tenofovir disoproxil fumarate, lamivudine, and dolutegravir (TLD). We modeled the weights pre- and postswitch using a 2-phase model with linear trend preswitch and an inverted exponential function postswitch. We estimated an 18-month excess weight gain by comparing the projected weight with that expected using the preswitch rate., Results: A total of 18 662 individuals were included in our analysis, with 55% switching from efavirenz (EFV) and 45% from nevirapine (NVP). Of the studied individuals, 51% were female, and the median age and body mass index (BMI) were 51 years and 22 kg/m2, respectively. For the overall population, the rate of weight gain increased from 0.47 kg/year preswitch to 0.77 kg/year, with higher increases for females (0.57 kg/year to 0.96 kg/year) than males (0.34 kg/year to 0.62 kg/year). The rate of weight gain for individuals switching from EFV-based regimens significantly increased from 0.57 kg/year preswitch to 1.11 kg/year postswitch but remained stable at 0.35 kg/year preswitch vs 0.32 kg/year postswitch for individuals switching from NVP-based regimens., Conclusions: Switching from NNRTI-based regimens to TLD is associated with a modest increase in the rate of weight gain, with the preswitch NNRTI being the key determinant of the amount of weight gain experienced postswitch., Competing Interests: Potential conflicts of interest. K.B. received research funding from Gilead Sciences and served on advisory boards for Gilead Sciences and Theratechnologies. All other authors report no potential conflicts. S.K.G. has received grant support from the National Institutes of Health and ViiV Healthcare and has participated in data safetymonitoring boards or advisory boards for Gilead Sciences and ViiV Healthcare., (© The Author(s) 2023. Published by Oxford University Press on behalf of Infectious Diseases Society of America.)
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- 2023
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17. Assessing HIV-infected patient retention in a program of differentiated care in sub-Saharan Africa: a G-estimation approach.
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Yiannoutsos CT, Wools-Kaloustian K, Musick BS, Kosgei R, Kimaiyo S, and Siika A
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- Humans, Male, Female, Kenya, Adult, Retention in Care statistics & numerical data, Africa South of the Sahara, Middle Aged, HIV Infections drug therapy
- Abstract
Differentiated care delivery aims to simplify care of people living with HIV, reflect their preferences, reduce burdens on the healthcare system, maintain care quality and preserve resources. However, assessing program effectiveness using observational data is difficult due to confounding by indication and randomized trials may be infeasible. Also, benefits can reach patients directly, through enrollment in the program, and indirectly, by increasing quality of and accessibility to care. Low-risk express care (LREC), the program under evaluation, is a nurse-centered model which assigns patients stable on ART to a nurse every two months and a clinician every third visit, reducing annual clinician visits by two thirds. Study population is comprised of 16,832 subjects from 15 clinics in Kenya. We focus on patient retention in care based on whether the LREC program is available at a clinic and whether the patient is enrolled in LREC. We use G-estimation to assess the effect on retention of two "strategies": (i) program availability but no enrollment; (ii) enrollment at an available program; versus no program availability. Compared to no availability, LREC results in a non-significant increase in patient retention, among patients not enrolled in the program (indirect effect), while enrollment in LREC is associated with a significant extension of the time retained in care (direct effect). G-estimation provides an analytical framework useful to the assessment of similar programs using observational data., (© 2023 Walter de Gruyter GmbH, Berlin/Boston.)
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- 2023
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18. Semiparametric marginal regression for clustered competing risks data with missing cause of failure.
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Zhou W, Bakoyannis G, Zhang Y, and Yiannoutsos CT
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- Humans, Likelihood Functions, Proportional Hazards Models, Computer Simulation, Incidence, Models, Statistical
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Clustered competing risks data are commonly encountered in multicenter studies. The analysis of such data is often complicated due to informative cluster size (ICS), a situation where the outcomes under study are associated with the size of the cluster. In addition, the cause of failure is frequently incompletely observed in real-world settings. To the best of our knowledge, there is no methodology for population-averaged analysis with clustered competing risks data with an ICS and missing causes of failure. To address this problem, we consider the semiparametric marginal proportional cause-specific hazards model and propose a maximum partial pseudolikelihood estimator under a missing at random assumption. To make the latter assumption more plausible in practice, we allow for auxiliary variables that may be related to the probability of missingness. The proposed method does not impose assumptions regarding the within-cluster dependence and allows for ICS. The asymptotic properties of the proposed estimators for both regression coefficients and infinite-dimensional parameters, such as the marginal cumulative incidence functions, are rigorously established. Simulation studies show that the proposed method performs well and that methods that ignore the within-cluster dependence and the ICS lead to invalid inferences. The proposed method is applied to competing risks data from a large multicenter HIV study in sub-Saharan Africa where a significant portion of causes of failure is missing., (© The Author 2022. Published by Oxford University Press.)
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- 2023
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19. The Effect of HIV Treatment Interruption on Subsequent Immunological Response.
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Thomadakis C, Yiannoutsos CT, Pantazis N, Diero L, Mwangi A, Musick BS, Wools-Kaloustian K, and Touloumi G
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- Humans, Anti-Retroviral Agents therapeutic use, CD4 Lymphocyte Count, Linear Models, HIV Infections drug therapy, HIV Infections epidemiology, Anti-HIV Agents therapeutic use
- Abstract
Recovery of CD4-positive T lymphocyte count after initiation of antiretroviral therapy (ART) has been thoroughly examined among people with human immunodeficiency virus infection. However, immunological response after restart of ART following care interruption is less well studied. We compared CD4 cell-count trends before disengagement from care and after ART reinitiation. Data were obtained from the East Africa International Epidemiology Databases to Evaluate AIDS (IeDEA) Collaboration (2001-2011; n = 62,534). CD4 cell-count trends before disengagement, during disengagement, and after ART reinitiation were simultaneously estimated through a linear mixed model with 2 subject-specific knots placed at the times of disengagement and treatment reinitiation. We also estimated CD4 trends conditional on the baseline CD4 value. A total of 10,961 patients returned to care after disengagement from care, with the median gap in care being 2.7 (interquartile range, 2.1-5.4) months. Our model showed that CD4 cell-count increases after ART reinitiation were much slower than those before disengagement. Assuming that disengagement from care occurred 12 months after ART initiation and a 3-month treatment gap, CD4 counts measured at 3 years since ART initiation would be lower by 36.5 cells/μL than those obtained under no disengagement. Given that poorer CD4 restoration is associated with increased mortality/morbidity, specific interventions targeted at better retention in care are urgently required., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.)
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- 2023
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20. Global HIV prevention, care and treatment services for children: a cross-sectional survey from the International Epidemiology Databases to Evaluate AIDS (IeDEA) consortium.
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Vreeman RC, Yiannoutsos CT, Yusoff NKN, Wester CW, Edmonds A, Ofner S, Davies MA, Leroy V, Lumbiganon P, de Menezes Succi RC, Twizere C, Brown S, Bolton-Moore C, Takassi OE, Scanlon M, Martin R, and Wools-Kaloustian K
- Subjects
- Pregnancy, Female, Humans, Child, Cross-Sectional Studies, Infectious Disease Transmission, Vertical, Counseling, Acquired Immunodeficiency Syndrome epidemiology, Acquired Immunodeficiency Syndrome prevention & control, HIV Infections drug therapy, HIV Infections epidemiology, HIV Infections prevention & control, Anti-HIV Agents therapeutic use
- Abstract
Objectives: To assess access children with HIV have to comprehensive HIV care services, to longitudinally evaluate the implementation and scale-up of services, and to use site services and clinical cohort data to explore whether access to these services influences retention in care., Methods: A cross-sectional standardised survey was completed in 2014-2015 by sites providing paediatric HIV care across regions of the International Epidemiology Databases to Evaluate AIDS (IeDEA) consortium. We developed a comprehensiveness score based on the WHO's nine categories of essential services to categorise sites as 'low' (0-5), 'medium', (6-7) or 'high' (8-9). When available, comprehensiveness scores were compared with scores from a 2009 survey. We used patient-level data with site services to investigate the relationship between the comprehensiveness of services and retention., Results: Survey data from 174 IeDEA sites in 32 countries were analysed. Of the WHO essential services, sites were most likely to offer antiretroviral therapy (ART) provision and counselling (n=173; 99%), co-trimoxazole prophylaxis (168; 97%), prevention of perinatal transmission services (167; 96%), outreach for patient engagement and follow-up (166; 95%), CD4 cell count testing (126; 88%), tuberculosis screening (151; 87%) and select immunisation services (126; 72%). Sites were less likely to offer nutrition/food support (97; 56%), viral load testing (99; 69%) and HIV counselling and testing (69; 40%). 10% of sites rated 'low', 59% 'medium' and 31% 'high' in the comprehensiveness score. The mean comprehensiveness of services score increased significantly from 5.6 in 2009 to 7.3 in 2014 (p<0.001; n=30). Patient-level analysis of lost to follow-up after ART initiation estimated the hazard was highest in sites rated 'low' and lowest in sites rated 'high'., Conclusion: This global assessment suggests the potential care impact of scaling-up and sustaining comprehensive paediatric HIV services. Meeting recommendations for comprehensive HIV services should remain a global priority., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2023
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21. Same-Day Antiretroviral Therapy Initiation as a Predictor of Loss to Follow-up and Viral Suppression Among People With Human Immunodeficiency Virus in Sub-Saharan Africa.
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Ross J, Brazier E, Fatti G, Jaquet A, Tanon A, Haas AD, Diero L, Castelnuovo B, Yiannoutsos CT, Nash D, Anastos KM, and Yotebieng M
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- Adult, Humans, HIV, Follow-Up Studies, Africa South of the Sahara epidemiology, HIV Infections drug therapy, HIV Infections epidemiology, Anti-HIV Agents therapeutic use
- Abstract
Background: Treat-All guidelines recommend initiation of antiretroviral therapy (ART) for all people with HIV (PWH) on the day of diagnosis when possible, yet uncertainty exists about the impact of same-day ART initiation on subsequent care engagement. We examined the association of same-day ART initiation with loss to follow-up and viral suppression among patients in 11 sub-Saharan African countries., Methods: We included ART-naive adult PWH from sites participating in the International epidemiology Databases to Evaluate AIDS (IeDEA) consortium who enrolled in care after Treat-All implementation and prior to January 2019. We used multivariable Cox regression to estimate the association between same-day ART initiation and loss to follow-up and Poisson regression to estimate the association between same-day ART initiation and 6-month viral suppression., Results: Among 29 017 patients from 63 sites, 18 584 (64.0%) initiated ART on the day of enrollment. Same-day ART initiation was less likely among those with advanced HIV disease versus early-stage disease. Loss to follow-up was significantly lower among those initiating ART ≥1 day of enrollment, compared with same-day ART initiators (20.6% vs 27.7%; adjusted hazard ratio: .66; 95% CI .57-.76). No difference in viral suppression was observed by time to ART initiation (adjusted rate ratio: 1.00; 95% CI: .98-1.02)., Conclusions: Patients initiating ART on the day of enrollment were more frequently lost to follow-up than those initiating later but were equally likely to be virally suppressed. Our findings support recent World Health Organization recommendations for providing tailored counseling and support to patients who accept an offer of same-day ART., Competing Interests: Potential conflicts of interest. D. N. received research support from Pfizer, Inc; payment or honoraria for lectures, presentations, speaker’s bureaus, manuscript writing, or educational events from various academic lectures at universities (paid to author); and consulting fees from Epidemic Intelligence, LLC, and Medscape. J. R. reports payment or honoraria for lectures, presentations, speaker’s bureaus, manuscript writing, or educational events for Grand Rounds speaker in 2019 (paid to author). E. B. reports support from the National Institutes of Health (NIH). G. F. reports support from International Epidemiologic Databases to Evaluate AIDS–Southern Africa, using funding provided by the NIH (funding provided to Kheth’Impilo AIDS Free Living [nonprofit]). B. C. reports support from NIH (D43 TW 009771: names of PD/Principal Investigators: Castelnuovo/Kambugu/Manabe) and the European & Developing Countries Clinical Trials Partnership (TWA 2017GSF-1936: Castelnuovo). C. T. Y. and K. M. A. report grants or contracts and support for attending meetings and/or travel from NIH (paid to institution). M. Y. reports grants or contracts from NIH: U01AI096299, R01HD087993, R01HD105526, and U54CA254568. All other authors report no potential conflicts. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed., (© The Author(s) 2022. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
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- 2023
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22. High Unreported Mortality in Children and Youth (<25 Years) Living With HIV Who Were Lost to Care From Antiretroviral Therapy Programs in Southern Africa: Results From a Multicountry Tracing Study.
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Nyakato P, Christ B, Anderegg N, Muhairwe J, Jefferys L, van Dijk J, Vinikoor MJ, van Lettow M, Chimbetete C, Phiri SJ, Egger M, Ballif M, Yiannoutsos CT, Schomaker M, Kassanjee R, Davies MA, and Cornell M
- Subjects
- Child, Infant, Young Adult, Humans, Adolescent, Anti-Retroviral Agents therapeutic use, Africa, Southern epidemiology, Proportional Hazards Models, Lost to Follow-Up, HIV Infections drug therapy, Anti-HIV Agents therapeutic use
- Abstract
Background: Antiretroviral therapy program mortality maybe underestimated if deceased patients are misclassified as lost., Methods: We used two-stage inverse probability weighting to account for probability of being: sampled for tracing and found by the tracer., Results: Among 680 children and youth aged <25 years on antiretroviral therapy who were lost and traced in Southern Africa between October 2017 and November 2019, estimated mortality was high at 9.1% (62/680). After adjusting for measured covariates and within-site clustering, mortality remained lower for young adults aged 20-24 years compared with infants aged <2 years [adjusted hazard ratio: 0.40 (95% confidence interval: 0.31 to 0.51)]., Conclusions: Our study confirms high unreported mortality in children and youth who are lost and the need for tracing to assess vital status among those who are lost to accurately report on program mortality., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2022 The Author(s). Published by Wolters Kluwer Health, Inc.)
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- 2022
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23. Weight Gain Among Treatment-Naïve Persons With HIV Receiving Dolutegravir in Kenya.
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Bourgi K, Ofner S, Musick B, Griffith B, Diero L, Wools-Kaloustian K, Yiannoutsos CT, and Gupta SK
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- Humans, Female, Male, Thinness drug therapy, Kenya, Heterocyclic Compounds, 3-Ring therapeutic use, Oxazines therapeutic use, Pyridones therapeutic use, Reverse Transcriptase Inhibitors therapeutic use, Weight Gain, HIV Infections drug therapy, HIV Infections epidemiology, Tuberculosis drug therapy, HIV Integrase Inhibitors therapeutic use
- Abstract
Background: Several recent studies have linked integrase strand transfer inhibitors (INSTI) with increased weight gain., Setting: The effects of sex on weight gain with dolutegravir (DTG)-based antiretroviral therapy (ART) among treatment-naïve participants in a lower-income, sub-Saharan population with high rates of pre-ART underweight and tuberculosis (TB) coinfection are unknown., Methods: Our analysis included treatment-naïve participants in Kenya and starting their first treatment regimen between January 1, 2015, and September 30, 2018. Participants were grouped into 2 cohorts based on the initial treatment regimen [DTG vs. nonnucleoside reverse transcriptase inhibitors (NNRTI)]. We modelled weight changes over time using a multivariable nonlinear mixed-effect model, with participant as a random effect. Logistic regression models were constructed to evaluate the association between different variables with extreme increase in body mass index (≥10% increase)., Results: Seventeen thousand forty-four participants met our inclusion criteria. Sixty-two percent of participants were women, 6% were receiving active TB therapy, and 97% were on NNRTI-based regimens. Participants starting DTG-based regimens were more likely to gain weight when compared with participants starting NNRTI-based regimens. Female participants starting DTG-based regimens experienced the highest weight gain compared with other participants (mean gain of 6.1 kgs at 18 months). Female participants receiving DTG-based regimens, along with participants with lower CD4 cell counts, underweight at baseline, and those receiving active TB therapy were also at higher risk for extreme body mass index increase., Conclusions: Our study in a lower-income sub-Saharan African population confirms higher weight gain with DTG-based regimens compared with traditional ART for treatment-naïve patients., Competing Interests: K.B. reports having received advisory fees and research grant funding from Gilead Sciences. S.K.G. reports having received advisory fees from Gilead Sciences and ViiV Healthcare and an unrestricted grant related to use of dolutegravir from ViiV Healthcare. The remaining authors have no conflicts of interest to disclose., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2022
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24. Contraceptive implant use duration is not associated with breakthrough pregnancy among women living with HIV and using efavirenz: a retrospective, longitudinal analysis.
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Stalter RM, Amorim G, Mocello AR, Jakait B, Shepherd BE, Musick B, Bernard C, Bukusi EA, Wools-Kaloustian K, Cohen CR, Yiannoutsos CT, and Patel RC
- Subjects
- Adolescent, Adult, Alkynes, Benzoxazines, Contraceptive Agents, Cyclopropanes, Female, Humans, Levonorgestrel pharmacokinetics, Levonorgestrel therapeutic use, Middle Aged, Pregnancy, Retrospective Studies, Young Adult, HIV Infections drug therapy, HIV Infections epidemiology, Nevirapine therapeutic use
- Abstract
Introduction: Contraceptive implants containing etonogestrel and levonorgestrel have emerged as popular contraceptive options among women in areas of high HIV burden in sub-Saharan Africa. However, recent pharmacokinetic data have shown drug-drug interactions between implants and efavirenz-containing antiretroviral therapy (ART), reducing the effectiveness of the implants. Here, we evaluated pregnancy incidence in 6-month intervals following implant initiation among women using efavirenz and contraceptive implants to assess whether the risk of breakthrough pregnancy is higher after specific periods of implant use., Methods: We used data from a retrospective longitudinal analysis of women living with HIV ages 18-45 years in western Kenya who attended HIV-care facilities between 2011 and 2015. We used Cox proportional hazard models to compute hazard ratios (HRs) for breakthrough pregnancy by implant type and ART regimen. Depending on the model, we adjusted for socio-demographic and clinical factors, programme, site and interaction between calendar time and ART regimen. We utilized inverse probability weights (IPWs) to account for three sampling phases (electronic medical record [EMR], chart review and phone interview) and calculated overall parameter estimates., Results: Women contributed 14,768 woman-years from the largest sampling phase (EMR). The median age was 31 years. Women used etonogestrel implants for 26-69% of the time and levonorgestrel implants for 7-31% of the time, depending on the sampling phase. Women used efavirenz, nevirapine or no ART for 27-33%, 40-46% and 15-26% of follow-ups, respectively. When combining sampling phases, there was little evidence to suggest that the relative hazard of pregnancy among efavirenz-containing ART users relative to nevirapine-containing ART changed with length of time on implants: IPW-adjusted HR of 3.1 (CI: [1.5; 6.4]) at 12 months, 3.4 (CI: [1.8; 6.3]) at 24 months, 3.8 (CI: [1.9; 7.7]) at 36 months and 4.2 (CI: [1.6; 11.1]) at 48 months (interaction p-value = 0.88). Similarly, no significant change in HRs over time was found when comparing women not using ART to nevirapine-containing ART users (interaction p-value = 0.49)., Conclusions: We did not find evidence to suggest implants being more fallible from drug-drug interactions with efavirenz at later time intervals of implant use. Thus, we would not recommend shortening the duration of implant use or replacing implants sooner when concomitantly used with efavirenz., (© 2022 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)
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- 2022
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25. Site-Level Comprehensiveness of Care Is Associated with Individual Clinical Retention Among Adults Living with HIV in International Epidemiology Databases to Evaluate AIDS, a Global HIV Cohort Collaboration, 2000-2016.
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Wada PY, Kim A, Jayathilake K, Duda SN, Abo Y, Althoff KN, Cornell M, Musick B, Brown S, Sohn AH, Chan YJ, Wools-Kaloustian KK, Nash D, Yiannoutsos CT, Cesar C, McGowan CC, and Rebeiro PF
- Subjects
- Adult, Cohort Studies, Female, Humans, Infectious Disease Transmission, Vertical, Acquired Immunodeficiency Syndrome drug therapy, Anti-HIV Agents therapeutic use, HIV Infections drug therapy, HIV Infections epidemiology, Retention in Care
- Abstract
Retention in care (RIC) reduces HIV transmission and associated morbidity and mortality. We examined whether delivery of comprehensive services influenced individual RIC within the International epidemiology Databases to Evaluate AIDS (IeDEA) network. We collected site data through IeDEA assessments 1.0 (2000-2009) and 2.0 (2010-2016). Each site received a comprehensiveness score for service availability (1 = present, 0 = absent), with tallies ranging from 0 to 7. We obtained individual-level cohort data for adults with at least one visit from 2000 to 2016 at sites responding to either assessment. Person-time was recorded annually, with RIC defined as completing two visits at least 90 days apart in each calendar year. Multivariable modified Poisson regression clustered by site yielded risk ratios and predicted probabilities for individual RIC by comprehensiveness. Among 347,060 individuals in care at 122 sites with 1,619,558 person-years of follow-up, 69.8% of person-time was retained in care, varying by region from 53.8% (Asia-Pacific) to 82.7% (East Africa); RIC improved by about 2% per year from 2000 to 2016 ( p = 0.012). Every site provided CD4
+ count testing, and >90% of individuals received care at sites that provided combination antiretroviral therapy adherence measures, prevention of mother-to-child transmission, tuberculosis screening, HIV-related prevention, and community tracing services. In adjusted models, individuals at sites with more comprehensive services had higher probabilities of RIC (0.71, 0.74, and 0.83 for scores 5, 6, and 7, respectively; p = 0.019). Within IeDEA, greater site-level comprehensiveness of services was associated with improved individual RIC. Much work remains in exploring this relationship, which may inform HIV clinical practice and health systems planning.- Published
- 2022
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26. Semiparametric regression on cumulative incidence function with interval-censored competing risks data and missing event types.
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Park J, Bakoyannis G, Zhang Y, and Yiannoutsos CT
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- Cohort Studies, Computer Simulation, Humans, Monte Carlo Method, Probability, Incidence
- Abstract
Competing risk data are frequently interval-censored, that is, the exact event time is not observed but only known to lie between two examination time points such as clinic visits. In addition to interval censoring, another common complication is that the event type is missing for some study participants. In this article, we propose an augmented inverse probability weighted sieve maximum likelihood estimator for the analysis of interval-censored competing risk data in the presence of missing event types. The estimator imposes weaker than usual missing at random assumptions by allowing for the inclusion of auxiliary variables that are potentially associated with the probability of missingness. The proposed estimator is shown to be doubly robust, in the sense that it is consistent even if either the model for the probability of missingness or the model for the probability of the event type is misspecified. Extensive Monte Carlo simulation studies show good performance of the proposed method even under a large amount of missing event types. The method is illustrated using data from an HIV cohort study in sub-Saharan Africa, where a significant portion of events types is missing. The proposed method can be readily implemented using the new function ciregic_aipw in the R package intccr., (© The Author 2021. Published by Oxford University Press.)
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- 2022
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27. Factors that differentiate COVID-19 vaccine intentions among Indiana parents: Implications for targeted vaccine promotion.
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Head KJ, Zimet GD, Yiannoutsos CT, Silverman RD, Sanner L, and Menachemi N
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- COVID-19 Vaccines, Child, Humans, Indiana, Intention, Parents, SARS-CoV-2, Vaccination, COVID-19 prevention & control, Vaccines
- Abstract
Given low rates of uptake of the COVID-19 vaccine for children 12-17 and 5-11 years old, research is needed to understand parental behaviors and behavioral intentions related to COVID-19 vaccination for their children. In the state of Indiana, we conducted a non-random, online survey of parents or caregivers (N = 10,266) about their COVID-19 vaccine intentions or behaviors, demographic characteristics, and potential motivating reasons for getting the vaccine. In terms of behaviors/intentions, 44.8% of participants indicated they were vaccine acceptors (i.e., had already had their children vaccinated or would as soon as it was possible), 13.0% indicated they were vaccine hesitators (i.e., wanted to wait and see), and 42.2% indicated they were vaccine rejecters (i.e., would not vaccinate or only would if mandated). Compared to vaccine rejecters, vaccine hesitators were more likely to be motivated by perceptions of vaccine safety and efficacy, normative influences such as close friends/family who had been vaccinated and a recommendation from a provider, as well as if they were vaccinated themselves. These findings have implications for the development of targeted vaccine promotion strategies, such as social norms messaging and a focus on vaccine safety, in order to increase COVID-19 vaccination for eligible children., (Copyright © 2022 Elsevier Inc. All rights reserved.)
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- 2022
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28. Virologic non-suppression and early loss to follow up among pregnant and non-pregnant adolescents aged 15-19 years initiating antiretroviral therapy in South Africa: a retrospective cohort study.
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Nyakato P, Schomaker M, Fatti G, Tanser F, Euvrard J, Sipambo N, Fox MP, Haas AD, Yiannoutsos CT, Davies MA, and Cornell M
- Subjects
- Adolescent, Female, Follow-Up Studies, Humans, Male, Pregnancy, Retrospective Studies, Risk Factors, South Africa epidemiology, HIV Infections drug therapy, HIV Infections epidemiology
- Abstract
Introduction: Older adolescents aged 15-19 years continue to have high rates of loss to follow up (LTFU), and high rates of virologic non-suppression (VNS) compared to younger adolescents and adults. Adolescent females are at risk of pregnancy, which puts those living with HIV at a dual vulnerability. Our study assessed the factors associated with VNS and LTFU in older adolescents (including pregnant females) who initiated antiretroviral therapy (ART) in South Africa., Methods: We included adolescents aged 15-19 years initiating ART between 2004 and 2019, with ≥ one viral load (VL) measurement between 4 and 24.5 months, and ≥ 6 months follow-up, from six South African cohorts of the International epidemiology Databases to Evaluate AIDS-Southern Africa (IeDEA-SA). We defined VNS as VL ≥400 copies/ml and LTFU as not being in care for ≥180 days from ART start and not known as transferred out of the clinic or dead in the first 24 months on ART. We examined factors associated with VNS and LTFU using Fine&Gray competing risk models., Results: We included a total of 2733 adolescents, 415 (15.2%) males, median (IQR) age at ART start of 18.6 (17.3, 19.4) years. Among females, 585/2318 (25.2%) were pregnant. Over the 24-month follow-up, 424 (15.5%) of all adolescents experienced VNS: range (11.1% pregnant females and 20.5% males). Over half of all adolescents were LTFU before any other event could occur. The hazard of VNS reduced with increasing age and CD4 count above 200 cells/μl at ART initiation among all adolescents having adjusted for all measured patient characteristics [adjusted sub-distribution hazard ratio (aSHR) 19 vs. 15 years: 0.50 (95% CI: 0.36, 0.68), aSHR: >500 vs. ≤200 cells/μl: 0.22 (95% CI: 0.16, 0.31)]. The effect of CD4 count persisted in pregnant females. Increasing age and CD4 count >200 cells/μl were risk factors for LTFU among all adolescents., Conclusions: Older adolescents had a high risk of LTFU shortly after ART start and a low risk of VNS, especially those initiating treatment during pregnancy. Interventions addressing adherence and retention should be incorporated into adolescent-friendly services to prevent VNS and LTFU and endeavour to trace lost adolescents as soon as they are identified., (© 2022 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)
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- 2022
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29. Effects of National Adoption of Treat-All Guidelines on Pre-Antiretroviral Therapy (ART) CD4 Testing and Viral Load Monitoring After ART initiation: A Regression Discontinuity Analysis.
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Brazier E, Tymejczyk O, Zaniewski E, Egger M, Wools-Kaloustian K, Yiannoutsos CT, Jaquet A, Althoff KN, Lee JS, Caro-Vega Y, Luz PM, Tanuma J, Niyongabo T, and Nash D
- Subjects
- Adolescent, Adult, Anti-Retroviral Agents therapeutic use, Antiretroviral Therapy, Highly Active, CD4 Lymphocyte Count, Child, Humans, Viral Load, Anti-HIV Agents therapeutic use, HIV Infections drug therapy
- Abstract
Background: The World Health Organization's Treat-All guidance recommends CD4 testing before initiating antiretroviral therapy (ART), and routine viral load (VL) monitoring (over CD4 monitoring) for patients on ART., Methods: We used regression discontinuity analyses to estimate changes in CD4 testing and VL monitoring among 547 837 ART-naive patients enrolling in human immunodeficiency virus (HIV) care during 2006-2018 at 225 clinics in 26 countries where Treat-All policies were adopted. We examined CD4 testing within 12 months before and VL monitoring 6 months after ART initiation among adults (≥20 years), adolescents (10-19 years), and children (0-9 years) in low/lower-middle-income countries (L/LMICs) and high/upper-middle-income countries (H/UMICs)., Results: Treat-All adoption led to an immediate decrease in pre-ART CD4 testing among adults in L/LMICs, from 57.0% to 48.1% (-8.9 percentage points [pp]; 95% CI: -11.0, -6.8), and a small increase in H/UMICs, from 90.1% to 91.7% (+1.6pp; 95% CI: 0.2, 3.0), with no changes among adolescents or children; decreases in pre-ART CD4 testing accelerated after Treat-All adoption in L/LMICs. In L/LMICs, VL monitoring after ART initiation was low among all patients in L/LMICs before Treat-All; while there was no immediate change at Treat-All adoption, VL monitoring trends significantly increased afterwards. VL monitoring increased among adults immediately after Treat-All adoption, from 58.2% to 61.1% (+2.9pp; 95% CI: 0.5, 5.4), with no significant changes among adolescents/children., Conclusions: While on-ART VL monitoring has improved in L/LMICs, Treat-All adoption has accelerated and disparately worsened suboptimal pre-ART CD4 monitoring, which may compromise care outcomes for individuals with advanced HIV., (© The Author(s) 2021. Published by Oxford University Press for the Infectious Diseases Society of America.)
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- 2021
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30. Achieving consistency in measures of HIV-1 viral suppression across countries: derivation of an adjustment based on international antiretroviral treatment cohort data.
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Johnson LF, Kariminia A, Trickey A, Yiannoutsos CT, Ekouevi DK, Minga AK, Pascom ARP, Han WM, Zhang L, Althoff KN, Rebeiro PF, Murenzi G, Ross J, Hsiao NY, and Marsh K
- Subjects
- Adult, Anti-Retroviral Agents therapeutic use, Child, Humans, Viral Load, Acquired Immunodeficiency Syndrome drug therapy, Anti-HIV Agents therapeutic use, HIV Infections drug therapy, HIV Infections epidemiology, HIV-1
- Abstract
Introduction: The third of the Joint United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 targets is to achieve a 90% rate of viral suppression (HIV viral load <1000 HIV-1 RNA copies/ml) in patients on antiretroviral treatment (ART) by 2020. However, some countries use different thresholds when reporting viral suppression, and there is thus a need for an adjustment to standardize estimates to the <1000 threshold. We aim to propose such an adjustment, to support consistent monitoring of progress towards the "third 90" target., Methods: We considered three possible distributions for viral loads in ART patients: Weibull, Pareto and reverse Weibull (imposing an upper limit but no lower limit on the log scale). The models were fitted to data on viral load distributions in ART patients in the International epidemiology Databases to Evaluate AIDS (IeDEA) collaboration (representing seven global regions) and the ART Cohort Collaboration (representing Europe), using separate random effects models for adults and children. The models were validated using data from the World Health Organization (WHO) HIV drug resistance report and the Brazilian national ART programme., Results: Models were calibrated using 921,157 adult and 37,431 paediatric viral load measurements, over 2010-2019. The Pareto and reverse Weibull models provided the best fits to the data, but for all models, the "shape" parameters for the viral load distributions differed significantly between regions. The Weibull model performed best in the validation against the WHO drug resistance survey data, while the Pareto model produced uncertainty ranges that were too narrow, relative to the validation data. Based on these analyses, we recommend using the reverse Weibull model. For example, if a country reports an 80% rate of viral suppression at <200 copies/ml, this model estimates the proportion virally suppressed at <1000 copies/ml is 88.3% (0.80
0.56 ), with uncertainty range 85.5-90.6% (0.800.70 -0.800.44 )., Conclusions: Estimates of viral suppression can change substantially depending on the threshold used in defining viral suppression. It is, therefore, important that viral suppression rates are standardized to the same threshold for the purpose of assessing progress towards UNAIDS targets. We have proposed a simple adjustment that allows this, and this has been incorporated into UNAIDS modelling software., (© 2021 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)- Published
- 2021
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31. Global HIV mortality trends among children on antiretroviral treatment corrected for under-reported deaths: an updated analysis of the International epidemiology Databases to Evaluate AIDS collaboration.
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Kassanjee R, Johnson LF, Zaniewski E, Ballif M, Christ B, Yiannoutsos CT, Nyakato P, Desmonde S, Edmonds A, Sudjaritruk T, Pinto J, Vreeman R, Dahourou DL, Twizere C, Kariminia A, Carlucci JG, Kasozi C, and Davies MA
- Subjects
- Adolescent, Africa, Southern, Anti-Retroviral Agents therapeutic use, Child, Cohort Studies, Humans, Acquired Immunodeficiency Syndrome drug therapy, Anti-HIV Agents therapeutic use, HIV Infections drug therapy, HIV Infections epidemiology
- Abstract
Introduction: The Joint United Nations Programme on HIV/AIDS (UNAIDS) projections of paediatric HIV prevalence and deaths rely on the International epidemiology Databases to Evaluate AIDS (IeDEA) consortium for mortality estimates among children living with HIV (CHIV) receiving antiretroviral therapy (ART). Previous estimates, based on data through 2014, may no longer be accurate due to expanded paediatric HIV care and treatment eligibility, and the possibility of unreported deaths in CHIV considered lost to follow-up (LTFU). We therefore estimated all-cause mortality and its trends in CHIV (<15 years old) on ART using extended and new IeDEA data., Methods: We analysed (i) IeDEA observational data from CHIV in routine care globally, and (ii) novel data from an IeDEA tracing study that determined outcomes in a sample of CHIV after being LTFU in southern Africa. We included 45,711 CHIV on ART during 2004 to 2017 at 72 programmes in Africa, Asia-Pacific and Latin America. We used mixed effects Poisson regression to estimate mortality by age, sex, CD4 at ART start, time on ART, region and calendar year. For Africa, in an adjusted analysis that accounts for unreported deaths among those LTFU, we first modified the routine data by simulating mortality outcomes within six months after LTFU, based on a Gompertz survival model fitted to the tracing data (n = 221)., Results: Observed mortality rates were 1.8 (95% CI: 1.7 to 1.9) and 9.4 (6.3 to 13.4) deaths per 100 person-years in the routine and tracing data, respectively. We found strong evidence of higher mortality at shorter ART durations, lower CD4 values, and in infancy. Averaging over covariate patterns, the adjusted mortality rate was 54% higher than the unadjusted rate. In unadjusted analyses, mortality reduced by an average 60% and 73% from 2005 to 2017, within and outside of Africa, respectively. In the adjusted analysis for Africa, this temporal reduction was 42%., Conclusions: Mortality rates among CHIV have decreased substantially over time. However, when accounting for worse outcomes among those LTFU, mortality estimates increased and temporal improvements were slightly reduced, suggesting caution in interpreting analyses based only on programme data. The improved and updated IeDEA estimates on mortality among CHIV on ART support UNAIDS efforts to accurately model global HIV statistics., (© 2021 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)
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- 2021
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32. Pregnancies among women living with HIV using contraceptives and antiretroviral therapy in western Kenya: a retrospective, cohort study.
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Patel RC, Amorim G, Jakait B, Shepherd BE, Mocello AR, Musick B, Bernard C, Onono M, Bukusi EA, Wools-Kaloustian K, Cohen CR, and Yiannoutsos CT
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- Cohort Studies, Female, Humans, Kenya epidemiology, Pregnancy, Retrospective Studies, Contraceptive Agents, HIV Infections drug therapy, HIV Infections epidemiology
- Abstract
Background: Preventing unintended pregnancies is paramount for women living with HIV (WLHIV). Previous studies have suggested that efavirenz-containing antiretroviral therapy (ART) reduces contraceptive effectiveness of implants, but there are uncertainties regarding the quality of the electronic medical record (EMR) data used in these prior studies., Methods: We conducted a retrospective, cohort study of EMR data from 2011 to 2015 among WLHIV of reproductive age accessing HIV care in public facilities in western Kenya. We validated a large subsample of records with manual chart review and telephone interviews. We estimated adjusted incidence rate ratios (aIRRs) with Poisson regression accounting for the validation sampling using inverse probability weighting and generalized raking., Results: A total of 85,324 women contributed a total of 170,845 women-years (w-y) of observation time; a subset of 5080 women had their charts reviewed, and 1285 underwent interviews. Among implant users, the aIRR of pregnancy for efavirenz- vs. nevirapine-containing ART was 1.9 (95% CI 1.6, 2.4) using EMR data only and 3.2 (95% CI 1.8, 5.7) when additionally using both chart review and interview validated data. Among efavirenz users, the aIRR of pregnancy for depomedroxyprogesterone acetate (DMPA) vs. implant use was 1.8 (95% CI 1.5, 2.1) in EMR only and 2.4 (95% CI 1.0, 6.1) using validated data., Conclusion: Pregnancy rates are higher when contraceptive implants are concomitantly used with efavirenz-containing ART, though rates were similar to leading alternative contraceptive methods such as DMPA. Our data provides policymakers, program staff, and WLHIV greater confidence in guiding their decision-making around contraceptive and ART options. Our novel, 3-phase validation sampling provides an innovative tool for using routine EMR data to improve the robustness of data quality., (© 2021. The Author(s).)
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- 2021
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33. Outcomes of retained and disengaged pregnant women living with HIV in Uganda.
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Kiragga AN, Twinomuhwezi E, Banturaki G, Achieng M, Nampala J, Bagaya I, Kigozi J, Castelnuovo B, Musick BS, Hazra R, Yiannoutsos CT, and Wools-Kaloustian KK
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- Adult, Breast Feeding, Female, Humans, Postpartum Period, Pregnancy, Pregnant Women, Uganda epidemiology, Viral Load, Young Adult, HIV Infections epidemiology, Pregnancy Complications, Infectious epidemiology
- Abstract
Introduction: Loss-to-follow-up among women living with HIV (WLWHIV) may lead to unfavorable outcomes for both mother and exposed infant. This study traced WLWHIV disengaged from care and their infants and compared their outcomes with those retained in care., Methods: The study included WLWHIV who initiated ART during pregnancy at six public clinics in Uganda. A woman was defined as disengaged (DW) if she had not attended her 6-week post-partum visit by 10 weeks after her estimated date of delivery. DW were matched with retained women (RW) by age and duration on ART. Nurse counselors traced all selected DW via telephone and community visits to assess vital status, infant HIV sero-status and maternal HIV viral load through blood draws., Results: Between July 2017 and July 2018, 734 women (359 DW and 375 RW) were identified for the study. Tracing was attempted on 349 DW and 160 (44.6%) were successfully located and enrolled in the study. They were matched with 162 RW. Among DW, 52 (32.5%) transferred to another health facility. Very few DW, 39.0% were HIV virally suppressed (<1000 copies/ml) compared to RW 89.5%, P<0.001). Among 138 babies born to DW, 4.3% tested positive for HIV compared to 1.4% among babies born to RW (P = 0.163)., Conclusion: Pregnant and breastfeeding WLWHIV who disengage from care are difficult to find in urban environments. Many have detectable viral loads, leading to the potential for an increased risk of MTCT. Efforts to reduce disengagement from care are critical for the successful elimination of MTCT in resource-limited settings., Competing Interests: The authors have declared that no competing interests exist.
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- 2021
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34. Compartmentalization of cerebrospinal fluid inflammation across the spectrum of untreated HIV-1 infection, central nervous system injury and viral suppression.
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Gisslen M, Keating SM, Spudich S, Arechiga V, Stephenson S, Zetterberg H, Di Germanio C, Blennow K, Fuchs D, Hagberg L, Norris PJ, Peterson J, Shacklett BL, Yiannoutsos CT, and Price RW
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- Adult, Anti-Retroviral Agents therapeutic use, Antiretroviral Therapy, Highly Active methods, Biomarkers blood, CD4-Positive T-Lymphocytes, CD8-Positive T-Lymphocytes, Central Nervous System immunology, Central Nervous System injuries, Cross-Sectional Studies, Female, HIV Infections cerebrospinal fluid, HIV Infections virology, HIV-1 pathogenicity, Humans, Inflammation immunology, Leukocyte Count, Male, Middle Aged, Neurofilament Proteins cerebrospinal fluid, RNA, Viral blood, Serum Albumin analysis, Sustained Virologic Response, HIV Infections immunology, HIV-1 immunology, Inflammation cerebrospinal fluid
- Abstract
Objective: To characterize the evolution of central nervous system (CNS) inflammation in HIV-1 infection applying a panel of cerebrospinal fluid (CSF) inflammatory biomarkers to grouped subjects representing a broad spectrum of systemic HIV-1 immune suppression, CNS injury and viral control., Methods: This is a cross-sectional analysis of archived CSF and blood samples, assessing concentrations of 10 functionally diverse soluble inflammatory biomarkers by immunoassays in 143 HIV-1-infected subjects divided into 8 groups: untreated primary HIV-1 infection (PHI); four untreated groups defined by their blood CD4+ T lymphocyte counts; untreated patients presenting with subacute HIV-associated dementia (HAD); antiretroviral-treated subjects with ≥1 years of plasma viral suppression; and untreated elite controllers. Twenty HIV-1-uninfected controls were included for comparison. Background biomarkers included blood CD4+ and CD8+ T lymphocytes, CSF and blood HIV-1 RNA, CSF white blood cell (WBC) count, CSF/blood albumin ratio, CSF neurofilament light chain (NfL), and CSF t-tau., Findings: HIV-1 infection was associated with a broad compartmentalized CSF inflammatory response that developed early in its course and changed with systemic disease progression, development of neurological injury, and viral suppression. CSF inflammation in untreated individuals without overt HAD exhibited at least two overall patterns of inflammation as blood CD4+ T lymphocytes decreased: one that peaked at 200-350 blood CD4+ T cells/μL and associated with lymphocytic CSF inflammation and HIV-1 RNA concentrations; and a second that steadily increased through the full range of CD4+ T cell decline and associated with macrophage responses and increasing CNS injury. Subacute HAD was distinguished by a third inflammatory profile with increased blood-brain barrier permeability and robust combined lymphocytic and macrophage CSF inflammation. Suppression of CSF and blood HIV-1 infections by antiretroviral treatment and elite viral control were associated with reduced CSF inflammation, though not fully to levels found in HIV-1 seronegative controls., Competing Interests: The authors have no competing interests that influenced the contents of this paper. However, the authors list the following general potential conflicts of interest: RWP had been a consultant to Merck and Co and had received an honorarium and travel support from AbbVie and Gilead Sciences for meeting presentations during part of the time of sample collections. MG has received research grants from Abbott, Baxter, Bristol-Myers Squibb, Gilead Sciences, GlaxoSmithKline, Merck, Pfizer, Roche and Tibotec, and he has received honoraria as a speaker and/or scientific advisor from Abbott/Abbvie, Amgen, Biogen, Bioinvent, Boehringer-Ingelheim, Bristol-Myers Squibb, Gilead Sciences, GlaxoSmithKline, Janssen-Cilag, MSD, Novocure, Novo Nordic, Pfizer, Roche and Tibotec. HZ has served at scientific advisory boards for Denali, Roche Diagnostics, Wave, Samumed, Siemens Healthineers, Pinteon Therapeutics and CogRx, has given lectures in symposia sponsored by Fujirebio, Alzecure and Biogen, and is a co-founder of Brain Biomarker Solutions in Gothenburg AB (BBS), which is a part of the GU Ventures Incubator Program. KB has served as a consultant, at advisory boards, or at data monitoring committees for Abcam, Axon, Biogen, JOMDD/Shimadzu. Julius Clinical, Lilly, MagQu, Novartis, Roche Diagnostics, and Siemens Healthineers, and is a co-founder of Brain Biomarker Solutions in Gothenburg AB (BBS), which is a part of the GU Ventures Incubator Program. Dr. Spudich has received an honorarium and travel support from AbbVie, Inc. for a meeting presentation. BLS has received research grants from Gilead Sciences, and an honorarium and travel support from Merck. SMK, SSS, VA, SS, CDG, DF, LH, JP, PJN, BLS and CTY report no conflicts. In no case were the above-listed activities related directly to the submitted work—neither to the conceptualization, study design, data collection, analysis, or manuscript preparation. This does not alter our adherence to PLOS ONE policies on sharing data and materials.
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- 2021
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35. How Many SARS-CoV-2-Infected People Require Hospitalization? Using Random Sample Testing to Better Inform Preparedness Efforts.
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Menachemi N, Dixon BE, Wools-Kaloustian KK, Yiannoutsos CT, and Halverson PK
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- Adolescent, Adult, Aged, Aged, 80 and over, Female, Forecasting, Humans, Indiana epidemiology, Male, Middle Aged, Prevalence, SARS-CoV-2, Young Adult, COVID-19 epidemiology, COVID-19 therapy, Civil Defense organization & administration, Civil Defense statistics & numerical data, Hospitalization statistics & numerical data, Hospitalization trends, Population Surveillance
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Context: Existing hospitalization ratios for COVID-19 typically use case counts in the denominator, which problematically underestimates total infections because asymptomatic and mildly infected persons rarely get tested. As a result, surge models that rely on case counts to forecast hospital demand may be inaccurately influencing policy and decision-maker action., Objective: Based on SARS-CoV-2 prevalence data derived from a statewide random sample (as opposed to relying on reported case counts), we determine the infection-hospitalization ratio (IHR), defined as the percentage of infected individuals who are hospitalized, for various demographic groups in Indiana. Furthermore, for comparison, we show the extent to which case-based hospitalization ratios, compared with the IHR, overestimate the probability of hospitalization by demographic group., Design: Secondary analysis of statewide prevalence data from Indiana, COVID-19 hospitalization data extracted from a statewide health information exchange, and all reported COVID-19 cases to the state health department., Setting: State of Indiana as of April 30, 2020., Main Outcome Measures: Demographic-stratified IHRs and case-hospitalization ratios., Results: The overall IHR was 2.1% and varied more by age than by race or sex. Infection-hospitalization ratio estimates ranged from 0.4% for those younger than 40 years to 9.2% for those older than 60 years. Hospitalization rates based on case counts overestimated the IHR by a factor of 10, but this overestimation differed by demographic groups, especially age., Conclusions: In this first study of the IHR based on population prevalence, our results can improve forecasting models of hospital demand-especially in preparation for the upcoming winter period when an increase in SARS CoV-2 infections is expected., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2021
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36. Virologic response of adolescents living with perinatally acquired HIV receiving antiretroviral therapy in the period of early adolescence (10-14 years) in South Africa.
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Nyakato P, Schomaker M, Sipambo N, Technau KG, Fatti G, Rabie H, Tanser F, Eley B, Euvrard J, Wood R, Tsondai PR, Yiannoutsos CT, Cornell M, and Davies MA
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- Adolescent, Adult, Africa, Southern, Child, Female, Humans, Male, Retrospective Studies, South Africa epidemiology, Viral Load, Anti-HIV Agents therapeutic use, HIV Infections drug therapy
- Abstract
Background and Objectives: Adolescents living with perinatally acquired HIV (ALPHIV) on antiretroviral therapy (ART) have been noted to have poorer adherence, retention and virologic control compared to adolescents with non-perinatally acquired HIV, children or adults. We aimed to describe and examine factors associated with longitudinal virologic response during early adolescence., Design: A retrospective cohort study., Methods: We included ALPHIV who initiated ART before age 9.5 years in South African cohorts of the International epidemiology Database to Evaluate AIDS-Southern Africa (IeDEA-SA) collaboration (2004-2016); with viral load (VL) values <400 copies/ml at age 10 years and at least one VL measurement after age 10 years. We used a log-linear quantile mixed model to assess factors associated with elevated (75th quantile) VLs., Results: We included 4396 ALPHIV, 50.7% were male, with median (interquartile range) age at ART start of 6.5 (4.5, 8.1) years. Of these, 74.9% were on a non-nucleoside reverse transcriptase inhibitor (NNRTI) at age 10 years. After adjusting for other patient characteristics, the 75th quantile VLs increased with increasing age being 3.13-fold (95% CI 2.66, 3.68) higher at age 14 versus age 10, were 3.25-fold (95% CI 2.81, 3.75) higher for patients on second-line protease-inhibitor and 1.81-fold for second-line NNRTI-based regimens (versus first-line NNRTI-based regimens). There was no difference by sex., Conclusions: As adolescents age between 10 and 14 years, they are increasingly likely to experience higher VL values, particularly if receiving second-line protease inhibitor or NNRTI-based regimens, which warrant adherence support interventions., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
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- 2021
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37. Bayesian estimation of SARS-CoV-2 prevalence in Indiana by random testing.
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Yiannoutsos CT, Halverson PK, and Menachemi N
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- Bayes Theorem, COVID-19 ethnology, COVID-19 virology, COVID-19 Testing statistics & numerical data, Hispanic or Latino statistics & numerical data, Humans, Indiana epidemiology, Indiana ethnology, Polymerase Chain Reaction, Prevalence, SARS-CoV-2 genetics, White People statistics & numerical data, COVID-19 diagnosis, COVID-19 epidemiology, SARS-CoV-2 isolation & purification
- Abstract
From 25 to 29 April 2020, the state of Indiana undertook testing of 3,658 randomly chosen state residents for the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus, the agent causing COVID-19 disease. This was the first statewide randomized study of COVID-19 testing in the United States. Both PCR and serological tests were administered to all study participants. This paper describes statistical methods used to address nonresponse among various demographic groups and to adjust for testing errors to reduce bias in the estimates of the overall disease prevalence in Indiana. These adjustments were implemented through Bayesian methods, which incorporated all available information on disease prevalence and test performance, along with external data obtained from census of the Indiana statewide population. Both adjustments appeared to have significant impact on the unadjusted estimates, mainly due to upweighting data in study participants of non-White races and Hispanic ethnicity and anticipated false-positive and false-negative test results among both the PCR and antibody tests utilized in the study., Competing Interests: The authors declare no competing interest., (Copyright © 2021 the Author(s). Published by PNAS.)
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- 2021
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38. Infection Fatality Ratios for COVID-19 Among Noninstitutionalized Persons 12 and Older: Results of a Random-Sample Prevalence Study.
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Blackburn J, Yiannoutsos CT, Carroll AE, Halverson PK, and Menachemi N
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- Adolescent, Adult, Aged, Child, Female, Humans, Indiana epidemiology, Male, Middle Aged, Pandemics, Prevalence, SARS-CoV-2, United States epidemiology, COVID-19 mortality, Independent Living
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- 2021
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39. A pseudo-likelihood method for estimating misclassification probabilities in competing-risks settings when true-event data are partially observed.
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Mpofu PB, Bakoyannis G, Yiannoutsos CT, Mwangi AW, and Mburu M
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- Adolescent, Adult, Aged, Aged, 80 and over, Bias, Female, Humans, Incidence, Male, Middle Aged, Probability, Young Adult, Likelihood Functions, Outcome Assessment, Health Care, Research Design
- Abstract
Outcome misclassification occurs frequently in binary-outcome studies and can result in biased estimation of quantities such as the incidence, prevalence, cause-specific hazards, cumulative incidence functions, and so forth. A number of remedies have been proposed to address the potential misclassification of the outcomes in such data. The majority of these remedies lie in the estimation of misclassification probabilities, which are in turn used to adjust analyses for outcome misclassification. A number of authors advocate using a gold-standard procedure on a sample internal to the study to learn about the extent of the misclassification. With this type of internal validation, the problem of quantifying the misclassification also becomes a missing data problem as, by design, the true outcomes are only ascertained on a subset of the entire study sample. Although, the process of estimating misclassification probabilities appears simple conceptually, the estimation methods proposed so far have several methodological and practical shortcomings. Most methods rely on missing outcome data to be missing completely at random (MCAR), a rather stringent assumption which is unlikely to hold in practice. Some of the existing methods also tend to be computationally-intensive. To address these issues, we propose a computationally-efficient, easy-to-implement, pseudo-likelihood estimator of the misclassification probabilities under a missing at random (MAR) assumption, in studies with an available internal-validation sample. We present the estimator through the lens of studies with competing-risks outcomes, though the estimator extends beyond this setting. We describe the consistency and asymptotic distributional properties of the resulting estimator, and derive a closed-form estimator of its variance. The finite-sample performance of this estimator is evaluated via simulations. Using data from a real-world study with competing-risks outcomes, we illustrate how the proposed method can be used to estimate misclassification probabilities. We also show how the estimated misclassification probabilities can be used in an external study to adjust for possible misclassification bias when modeling cumulative incidence functions., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)
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- 2020
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40. Lower rates of ART initiation and decreased retention among ART-naïve patients who consume alcohol enrolling in HIV care and treatment programs in Kenya and Uganda.
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Patsis I, Goodrich S, Yiannoutsos CT, Brown SA, Musick BS, Diero L, Kulzer JL, Bwana MB, Oyaro P, and Wools-Kaloustian KK
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- Adolescent, Adult, Female, HIV Infections epidemiology, Humans, Kenya epidemiology, Male, Middle Aged, Prevalence, Prospective Studies, Surveys and Questionnaires, Uganda epidemiology, Young Adult, Alcohol Drinking epidemiology, HIV Infections drug therapy, Patient Acceptance of Health Care statistics & numerical data
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Objectives: Almost 13 million people are estimated to be on antiretroviral therapy in Eastern and Southern Africa, and their disease course and program effectiveness could be significantly affected by the concurrent use of alcohol. Screening for alcohol use may be important to assess the prevalence of alcohol consumption and its impact on patient and programmatic outcomes., Methods: As part of this observational study, data on patient characteristics and alcohol consumption were collected on a cohort of 765 adult patients enrolling in HIV care in East Africa. Alcohol consumption was assessed with the AUDIT questionnaire at enrollment. Subjects were classified as consuming any alcohol (AUDIT score >0), hazardous drinkers (AUDIT score ≥8) and hyper drinkers (AUDIT score ≥16). The effects of alcohol consumption on retention in care, death and delays in antiretroviral therapy (ART) initiation were assessed through competing risk (Fine & Gray) models., Results: Of all study participants, 41.6% consumed alcohol, 26.7% were classified as hazardous drinkers, and 16.0% as hyper drinkers. Depending on alcohol consumption classification, men were 3-4 times more likely to consume alcohol compared to women. Hazardous drinkers (median age 32.8 years) and hyper drinkers (32.7 years) were slightly older compared to non-hazardous drinkers (30.7 years) and non-hyper drinkers (30.8 years), (p-values = 0.014 and 0.053 respectively). Median CD4 at enrollment was 330 cells/μl and 16% were classified World Health Organization (WHO) stage 3 or 4. There was no association between alcohol consumption and CD4 count or WHO stage at enrollment. Alcohol consumption was associated with significantly lower probability of ART initiation (adjusted sub-distribution hazard ratio aSHR = 0.77 between alcohol consumers versus non-consumers; p-value = 0.008), and higher patient non-retention in care (aSHR = 1.77, p-value = 0.023)., Discussion: Alcohol consumption is associated with significant delays in ART initiation and reduced retention in care for patients enrolling in HIV care and treatment programs in East Africa. Consequently, interventions that target alcohol consumption may have a significant impact on the HIV care cascade., Competing Interests: The authors have declared that no competing interests exist.
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- 2020
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41. Semiparametric regression and risk prediction with competing risks data under missing cause of failure.
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Bakoyannis G, Zhang Y, and Yiannoutsos CT
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- Cohort Studies, Computer Simulation, Humans, Likelihood Functions, Proportional Hazards Models, Risk Assessment methods
- Abstract
The cause of failure in cohort studies that involve competing risks is frequently incompletely observed. To address this, several methods have been proposed for the semiparametric proportional cause-specific hazards model under a missing at random assumption. However, these proposals provide inference for the regression coefficients only, and do not consider the infinite dimensional parameters, such as the covariate-specific cumulative incidence function. Nevertheless, the latter quantity is essential for risk prediction in modern medicine. In this paper we propose a unified framework for inference about both the regression coefficients of the proportional cause-specific hazards model and the covariate-specific cumulative incidence functions under missing at random cause of failure. Our approach is based on a novel computationally efficient maximum pseudo-partial-likelihood estimation method for the semiparametric proportional cause-specific hazards model. Using modern empirical process theory we derive the asymptotic properties of the proposed estimators for the regression coefficients and the covariate-specific cumulative incidence functions, and provide methodology for constructing simultaneous confidence bands for the latter. Simulation studies show that our estimators perform well even in the presence of a large fraction of missing cause of failures, and that the regression coefficient estimator can be substantially more efficient compared to the previously proposed augmented inverse probability weighting estimator. The method is applied using data from an HIV cohort study and a bladder cancer clinical trial.
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- 2020
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42. A semiparametric method for the analysis of outcomes during a gap in HIV care under incomplete outcome ascertainment.
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Bakoyannis G, Diero L, Mwangi A, Wools-Kaloustian KK, and Yiannoutsos CT
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Objectives: Estimation of the cascade of HIV care is essential for evaluating care and treatment programs, informing policy makers and assessing targets such as 90-90-90. A challenge to estimating the cascade based on electronic health record concerns patients "churning" in and out of care. Correctly estimating this dynamic phenomenon in resource-limited settings, such as those found in sub-Saharan Africa, is challenging because of the significant death under-reporting. An approach to partially recover information on the unobserved deaths is a double-sampling design, where a small subset of individuals with a missed clinic visit is intensively outreached in the community to actively ascertain their vital status. This approach has been adopted in several programs within the East Africa regional IeDEA consortium, the context of our motivating study. The objective of this paper is to propose a semiparametric method for the analysis of competing risks data with incomplete outcome ascertainment., Methods: Based on data from double-sampling designs, we propose a semiparametric inverse probability weighted estimator of key outcomes during a gap in care, which are crucial pieces of the care cascade puzzle., Results: Simulation studies suggest that the proposed estimators provide valid estimates in settings with incomplete outcome ascertainment under a set of realistic assumptions. These studies also illustrate that a naïve complete-case analysis can provide seriously biased estimates. The methodology is applied to electronic health record data from the East Africa IeDEA Consortium to estimate death and return to care during a gap in care., Conclusions: The proposed methodology provides a robust approach for valid inferences about return to care and death during a gap in care, in settings with death under-reporting. Ultimately, the resulting estimates will have significant consequences on program construction, resource allocation, policy and decision making at the highest levels., Competing Interests: Competing interests: Authors state no conflict of interest.
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- 2020
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43. Population Point Prevalence of SARS-CoV-2 Infection Based on a Statewide Random Sample - Indiana, April 25-29, 2020.
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Menachemi N, Yiannoutsos CT, Dixon BE, Duszynski TJ, Fadel WF, Wools-Kaloustian KK, Unruh Needleman N, Box K, Caine V, Norwood C, Weaver L, and Halverson PK
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- Adolescent, Adult, Aged, Aged, 80 and over, COVID-19, Child, Coronavirus Infections ethnology, Ethnicity statistics & numerical data, Female, Humans, Indiana epidemiology, Male, Middle Aged, Pandemics, Pneumonia, Viral ethnology, Prevalence, Racial Groups statistics & numerical data, Young Adult, Coronavirus Infections epidemiology, Pneumonia, Viral epidemiology, Public Health Surveillance methods
- Abstract
Population prevalence of persons infected with SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), varies by subpopulation and locality. U.S. studies of SARS-CoV-2 infection have examined infections in nonrandom samples (1) or seroprevalence in specific populations* (2), which are limited in their generalizability and cannot be used to accurately calculate infection-fatality rates. During April 25-29, 2020, Indiana conducted statewide random sample testing of persons aged ≥12 years to assess prevalence of active infection and presence of antibodies to SARS-CoV-2; additional nonrandom sampling was conducted in racial and ethnic minority communities to better understand the impact of the virus in certain racial and ethnic minority populations. Estimates were adjusted for nonresponse to reflect state demographics using an iterative proportional fitting method. Among 3,658 noninstitutionalized participants in the random sample survey, the estimated statewide point prevalence of active SARS-CoV-2 infection confirmed by reverse transcription-polymerase chain reaction (RT-PCR) testing was 1.74% (95% confidence interval [CI] = 1.10-2.54); 44.2% of these persons reported no symptoms during the 2 weeks before testing. The prevalence of immunoglobulin G (IgG) seropositivity, indicating past infection, was 1.09% (95% CI = 0.76-1.45). The overall prevalence of current and previous infections of SARS-CoV-2 in Indiana was 2.79% (95% CI = 2.02-3.70). In the random sample, higher overall prevalences were observed among Hispanics and those who reported having a household contact who had previously been told by a health care provider that they had COVID-19. By late April, an estimated 187,802 Indiana residents were currently or previously infected with SARS-CoV-2 (9.6 times higher than the number of confirmed cases [17,792]) (3), and 1,099 residents died (infection-fatality ratio = 0.58%). The number of reported cases represents only a fraction of the estimated total number of infections. Given the large number of persons who remain susceptible in Indiana, adherence to evidence-based public health mitigation and containment measures (e.g., social distancing, consistent and correct use of face coverings, and hand hygiene) is needed to reduce surge in hospitalizations and prevent morbidity and mortality from COVID-19., Competing Interests: All authors have completed and submitted the International Committee of Medical Journal Editors form for disclosure of potential conflicts of interest. Nir Menachemi reports a grant from State of Indiana which funded this study. Virginia Caine reports that she is a member of the MMWR Editorial Board. Brian E. Dixon and William F. Fadel report grants from the Indiana State Department of Health. Paul K. Halverson reports a grant from the State of Indiana. No other potential conflicts of interest were disclosed.
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- 2020
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44. Weight-for-age distributions among children with HIV on antiretroviral therapy in the International epidemiology Databases to Evaluate AIDS (IeDEA) multiregional consortium.
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Jesson J, Desmonde S, Yiannoutsos CT, Patten G, Malateste K, Duda SN, Kumarasamy N, Yotebieng M, Davies MA, Musick B, Leroy V, and Ciaranello A
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- Acquired Immunodeficiency Syndrome epidemiology, Adolescent, Africa, Central, Africa, Eastern, Africa, Southern, Age Distribution, Asia, Southeastern, Caribbean Region, Central America, Child, Child, Preschool, Cohort Studies, Databases, Factual, Female, HIV Infections epidemiology, Humans, Infant, Male, South America, World Health Organization, Acquired Immunodeficiency Syndrome drug therapy, Anti-HIV Agents therapeutic use, HIV Infections drug therapy
- Abstract
Objective: Pediatric antiretroviral therapy (ART) for children with HIV (CHIV) must be dosed appropriately for children's changing weights as they grow. To inform accurate estimates of ART formulations and doses needed, we described weight-for-age distributions among CHIV on ART in the IeDEA global pediatric collaboration between 2004 and 2016, using data from six regions (East, West, Central, and Southern Africa, Asia-Pacific, and Central/South America and the Caribbean)., Results: Overall, 59,862 children contributed to the analysis. Age and weight data were available from 530,080 clinical encounters for girls and 537,894 for boys. For each one-year age stratum from 0 to 15 years, we calculated the proportion of children in each of the weight bands designated by the World Health Organization as relevant to pediatric ART formulations: 0 to < 3 kg, 3 to < 6 kg, 6 to < 10 kg, 10 to < 14 kg, 14 to < 20 kg, 20 to < 25 kg, 25 to < 30 kg, 30 to < 35 kg, 35 to < 40 kg, 40 to < 45 kg, 45 to < 50 kg, 50 to < 55 kg, 55 to < 60 kg, and ≥ 60 kg. Data are reported for the entire cohort, as well as stratified by sex and IeDEA region, calendar year of ART use, and duration on ART at time of assessment (< 12 or ≥ 12 months), provided in data tables. These data are critical to improve the accuracy of forecasting and procurement of pediatric ART formulations as the pediatric HIV epidemic and pediatric HIV treatment strategies evolve.
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- 2020
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45. PS-SiZer map to investigate significant features of body-weight profile changes in HIV infected patients in the IeDEA Collaboration.
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Harezlak J, Sarwat S, Wools-Kaloustian K, Schomaker M, Balestre E, Law M, Kiertiburanakul S, Fox M, Huis In 't Veld D, Musick BS, and Yiannoutsos CT
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- Adult, Africa, Africa, Southern, Anti-HIV Agents therapeutic use, Biomarkers blood, Computer Simulation, Data Interpretation, Statistical, Female, Humans, Longitudinal Studies, Male, Anti-HIV Agents pharmacology, Body Weight drug effects, HIV Infections drug therapy, HIV Infections physiopathology, Weight Gain
- Abstract
Objectives: We extend the method of Significant Zero Crossings of Derivatives (SiZer) to address within-subject correlations of repeatedly collected longitudinal biomarker data and the computational aspects of the methodology when analyzing massive biomarker databases. SiZer is a powerful visualization tool for exploring structures in curves by mapping areas where the first derivative is increasing, decreasing or does not change (plateau) thus exploring changes and normalization of biomarkers in the presence of therapy., Methods: We propose a penalized spline SiZer (PS-SiZer) which can be expressed as a linear mixed model of the longitudinal biomarker process to account for irregularly collected data and within-subject correlations. Through simulations we show how sensitive PS-SiZer is in detecting existing features in longitudinal data versus existing versions of SiZer. In a real-world data analysis PS-SiZer maps are used to map areas where the first derivative of weight change after antiretroviral therapy (ART) start is significantly increasing, decreasing or does not change, thus exploring the durability of weight increase after the start of therapy. We use weight data repeatedly collected from persons living with HIV initiating ART in five regions in the International Epidemiologic Databases to Evaluate AIDS (IeDEA) worldwide collaboration and compare the durability of weight gain between ART regimens containing and not containing the drug stavudine (d4T), which has been associated with shorter durability of weight gain., Results: Through simulations we show that the PS-SiZer is more accurate in detecting relevant features in longitudinal data than existing SiZer variants such as the local linear smoother (LL) SiZer and the SiZer with smoothing splines (SS-SiZer). In the illustration we include data from 185,010 persons living with HIV who started ART with a d4T (53.1%) versus non-d4T (46.9%) containing regimen. The largest difference in durability of weight gain identified by the SiZer maps was observed in Southern Africa where weight gain in patients treated with d4T-containing regimens lasted 59.9 weeks compared to 133.8 weeks for those with non-d4T-containing regimens. In the other regions, persons receiving d4T-containing regimens experienced weight gains lasting 38-62 weeks versus 55-93 weeks in those receiving non-d4T-based regimens., Discussion: PS-SiZer, a SiZer variant, can handle irregularly collected longitudinal data and within-subject correlations and is sensitive in detecting even subtle features in biomarker curves., Competing Interests: The authors have declared that no competing interests exist.
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- 2020
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46. Nonparametric estimation of the cumulative incidence function under outcome misclassification using external validation data.
- Author
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Edwards JK, Bakoyannis G, Yiannoutsos CT, Mburu MW, and Cole SR
- Subjects
- Bias, Biostatistics, Computer Simulation, Confidence Intervals, HIV Infections therapy, Humans, Incidence, Kenya epidemiology, Monte Carlo Method, Outcome Assessment, Health Care classification, Statistics, Nonparametric, Validation Studies as Topic, Models, Statistical, Outcome Assessment, Health Care statistics & numerical data
- Abstract
Misclassification of outcomes or event types is common in health sciences research and can lead to serious bias when estimating the cumulative incidence functions in settings with competing risks. Recent work has shown how to estimate nonparametric cumulative incidence functions in the presence of nondifferential outcome misclassification when the misclassification probabilities are known. Here, we extend this approach to account for misclassification that is differential with respect to important predictors of the outcome using misclassification probabilities estimated from external validation data. Moreover, we propose a bootstrap approach in which the observations from both the main study data and the external validation study are resampled to allow the uncertainty in the misclassification probabilities to propagate through the analysis into the final confidence intervals, ensuring appropriate confidence interval coverage probabilities. The proposed estimator is shown to be uniformly consistent and simulation studies indicate that both the estimator and the standard error estimation approach perform well in finite samples. The methodology is applied to estimate the cumulative incidence of death and disengagement from HIV care in a large cohort of HIV infected individuals in sub-Saharan Africa, where a significant death underreporting issue leads to outcome misclassification. This analysis uses external validation data from a separate study conducted in the same country., (© 2019 John Wiley & Sons, Ltd.)
- Published
- 2019
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47. NONPARAMETRIC INFERENCE FOR MARKOV PROCESSES WITH MISSING ABSORBING STATE.
- Author
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Bakoyannis G, Zhang Y, and Yiannoutsos CT
- Abstract
This paper deals with the issue of nonparametric estimation of the transition probability matrix of a non-homogeneous Markov process with finite state space and partially observed absorbing state. We impose a missing at random assumption and propose a computationally efficient nonparametric maximum pseudolikelihood estimator (NPMPLE). The estimator depends on a parametric model that is used to estimate the probability of each absorbing state for the missing observations based, potentially, on auxiliary data. For the latter model we propose a formal goodness-of-fit test based on a residual process. Using modern empirical process theory we show that the estimator is uniformly consistent and converges weakly to a tight mean-zero Gaussian random field. We also provide methodology for simultaneous confidence band construction. Simulation studies show that the NPMPLE works well with small sample sizes and that it is robust against some degree of misspecification of the parametric model for the missing absorbing states. The method is illustrated using HIV data from sub-Saharan Africa to estimate the transition probabilities of death and disengagement from HIV care.
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- 2019
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48. Changes in rapid HIV treatment initiation after national "treat all" policy adoption in 6 sub-Saharan African countries: Regression discontinuity analysis.
- Author
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Tymejczyk O, Brazier E, Yiannoutsos CT, Vinikoor M, van Lettow M, Nalugoda F, Urassa M, Sinayobye JD, Rebeiro PF, Wools-Kaloustian K, Davies MA, Zaniewski E, Anderegg N, Liu G, Ford N, and Nash D
- Subjects
- Adult, Africa South of the Sahara epidemiology, Female, Health Policy legislation & jurisprudence, Humans, Longitudinal Studies, Male, Middle Aged, Regression Analysis, Time Factors, Anti-HIV Agents therapeutic use, HIV Infections drug therapy, HIV Infections epidemiology, Health Policy trends
- Abstract
Background: Most countries have formally adopted the World Health Organization's 2015 recommendation of universal HIV treatment ("treat all"). However, there are few rigorous assessments of the real-world impact of treat all policies on antiretroviral treatment (ART) uptake across different contexts., Methods and Findings: We used longitudinal data for 814,603 patients enrolling in HIV care between 1 January 2004 and 10 July 2018 in 6 countries participating in the global International epidemiology Databases to Evaluate AIDS (IeDEA) consortium: Burundi (N = 11,176), Kenya (N = 179,941), Malawi (N = 84,558), Rwanda (N = 17,396), Uganda (N = 96,286), and Zambia (N = 425,246). Using a quasi-experimental regression discontinuity design, we assessed the change in the proportion initiating ART within 30 days of enrollment in HIV care (rapid ART initiation) after country-level adoption of the treat all policy. A modified Poisson model was used to identify factors associated with failure to initiate ART rapidly under treat all. In each of the 6 countries, over 60% of included patients were female, and median age at enrollment ranged from 32 to 36 years. In all countries studied, national adoption of treat all was associated with large increases in rapid ART initiation. Significant increases in rapid ART initiation immediately after treat all policy adoption were observed in Rwanda, from 44.4% to 78.9% of patients (34.5 percentage points [pp], 95% CI 27.2 to 41.7; p < 0.001), Kenya (25.7 pp, 95% CI 21.8 to 29.5; p < 0.001), Burundi (17.7 pp, 95% CI 6.5 to 28.9; p = 0.002), and Malawi (12.5 pp, 95% CI 7.5 to 17.5; p < 0.001), while no immediate increase was observed in Zambia (0.4 pp, 95% CI -2.9 to 3.8; p = 0.804) and Uganda (-4.2 pp, 95% CI -9.0 to 0.7; p = 0.090). The rate of rapid ART initiation accelerated sharply following treat all policy adoption in Malawi, Uganda, and Zambia; slowed in Kenya; and did not change in Rwanda and Burundi. In post hoc analyses restricted to patients enrolling under treat all, young adults (16-24 years) and men were at increased risk of not rapidly initiating ART (compared to older patients and women, respectively). However, rapid ART initiation following enrollment increased for all groups as more time elapsed since treat all policy adoption. Study limitations include incomplete data on potential ART eligibility criteria, such as clinical status, pregnancy, and enrollment CD4 count, which precluded the assessment of rapid ART initiation specifically among patients known to be eligible for ART before treat all., Conclusions: Our analysis indicates that adoption of treat all policies had a strong effect on increasing rates of rapid ART initiation, and that these increases followed different trajectories across the 6 countries. Young adults and men still require additional attention to further improve rapid ART initiation., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2019
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49. Semiparametric competing risks regression under interval censoring using the R package intccr.
- Author
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Park J, Bakoyannis G, and Yiannoutsos CT
- Subjects
- Adult, Africa, Algorithms, Computer Simulation, Data Interpretation, Statistical, Databases, Factual, Female, HIV Infections therapy, Humans, Incidence, Likelihood Functions, Male, Models, Statistical, Monte Carlo Method, Odds Ratio, Programming Languages, Proportional Hazards Models, Regression Analysis, Software, Biometry methods, HIV Infections epidemiology, Risk Assessment methods
- Abstract
Background and Objective: Competing risk data are frequently interval-censored in real-world applications, that is, the exact event time is not precisely observed but is only known to lie between two time points such as clinic visits. This type of data requires special handling because the actual event times are unknown. To deal with this problem we have developed an easy-to-use open-source statistical software., Methods: An approach to perform semiparametric regression analysis of the cumulative incidence function with interval-censored competing risks data is the sieve maximum likelihood method based on B-splines. An important feature of this approach is that it does not impose restrictive parametric assumptions. Also, this methodology provides semiparametrically efficient estimates. Implementation of this methodology can be easily performed using our new R package intccr., Results: The R package intccr performs semiparametric regression analysis of the cumulative incidence function based on interval-censored competing risks data. It supports a large class of models including the proportional odds and the Fine-Gray proportional subdistribution hazards model as special cases. It also provides the estimated cumulative incidence functions for a particular combination of covariate values. The package also provides some data management functionality to handle data sets which are in a long format involving multiple lines of data per subject., Conclusions: The R package intccr provides a convenient and flexible software for the analysis of the cumulative incidence function based on interval-censored competing risks data., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)
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- 2019
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50. Research priorities to inform "Treat All" policy implementation for people living with HIV in sub-Saharan Africa: a consensus statement from the International epidemiology Databases to Evaluate AIDS (IeDEA).
- Author
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Yotebieng M, Brazier E, Addison D, Kimmel AD, Cornell M, Keiser O, Parcesepe AM, Onovo A, Lancaster KE, Castelnuovo B, Murnane PM, Cohen CR, Vreeman RC, Davies MA, Duda SN, Yiannoutsos CT, Bono RS, Agler R, Bernard C, Syvertsen JL, Sinayobye JD, Wikramanayake R, Sohn AH, von Groote PM, Wandeler G, Leroy V, Williams CF, Wools-Kaloustian K, and Nash D
- Subjects
- Africa South of the Sahara epidemiology, Databases, Factual, HIV Infections economics, HIV Infections epidemiology, HIV Infections immunology, Health Policy, Humans, Policy Making, Public Health economics, Public Health legislation & jurisprudence, HIV Infections drug therapy
- Abstract
Introduction: "Treat All" - the treatment of all people with HIV, irrespective of disease stage or CD4 cell count - represents a paradigm shift in HIV care that has the potential to end AIDS as a public health threat. With accelerating implementation of Treat All in sub-Saharan Africa (SSA), there is a need for a focused agenda and research to identify and inform strategies for promoting timely uptake of HIV treatment, retention in care, and sustained viral suppression and addressing bottlenecks impeding implementation., Methods: The Delphi approach was used to develop consensus around research priorities for Treat All implementation in SSA. Through an iterative process (June 2017 to March 2018), a set of research priorities was collectively formulated and refined by a technical working group and shared for review, deliberation and prioritization by more than 200 researchers, implementation experts, policy/decision-makers, and HIV community representatives in East, Central, Southern and West Africa., Results and Discussion: The process resulted in a list of nine research priorities for generating evidence to guide Treat All policies, implementation strategies and monitoring efforts. These priorities highlight the need for increased focus on adolescents, men, and those with mental health and substance use disorders - groups that remain underserved in SSA and for whom more effective testing, linkage and care strategies need to be identified. The priorities also reflect consensus on the need to: (1) generate accurate national and sub-national estimates of the size of key populations and describe those who remain underserved along the HIV-care continuum; (2) characterize the timeliness of HIV care and short- and long-term HIV care continuum outcomes, as well as factors influencing timely achievement of these outcomes; (3) estimate the incidence and prevalence of HIV-drug resistance and regimen switching; and (4) identify cost-effective and affordable service delivery models and strategies to optimize uptake and minimize gaps, disparities, and losses along the HIV-care continuum, particularly among underserved populations., Conclusions: Reflecting consensus among a broad group of experts, researchers, policy- and decision-makers, PLWH, and other stakeholders, the resulting research priorities highlight important evidence gaps that are relevant for ministries of health, funders, normative bodies and research networks., (© 2019 The Authors. Journal of the International AIDS Society published by John Wiley & Sons Ltd on behalf of the International AIDS Society.)
- Published
- 2019
- Full Text
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