Search

Context: Hepatitis C virus (HCV) infection may resolve (viral clearance), persist without complications, or cause end-stage liver disease (ESLD). The frequency and determinants of these outcomes are poorly understood.Objective: To assess the incidence and determinants of viral clearance and ESLD among persons who acquired HCV infection from injection drug use.Design and Setting: Community-based prospective cohort study with enrollment in 1988-1989 and a median follow-up of 8.8 years.Subjects: A total of 1667 persons aged 17 years or older with a history of injection drug use and an HCV antibody-positive test result during follow-up.Main Outcome Measures: Viral clearance was assessed in a subset of 919 patients and defined as failure to detect HCV RNA in at least 2 consecutive samples collected 5 or more months apart. End-stage liver disease was assessed at semiannual visits and by review of medical records and death certificates and defined by the presence of ascites, esophageal varices, or hepatic encephalopathy, or when ESLD was stated as a cause of death.Results: Viral clearance was observed in 90 persons who were compared with 722 with persistent viremia, while the viremia of 107 was not resolved. Viral clearance occurred more often in nonblacks (adjusted odds ratio [OR], 5.15; 95% confidence interval [CI], 2.60-10.17) and those not infected with human immunodeficiency virus (HIV) (adjusted OR, 2.19; 95% CI, 1.26-3.47). Forty cases of ESLD were observed throughout follow-up (incidence, 3.1 per 1000 person-years). In a multivariate model, risk of ESLD was higher for persons aged 38 years or older at enrollment (adjusted relative incidence, 3.67; 95% CI, 1.96-6.88) and who reported ingestion of more than 260 g of alcohol per week (adjusted relative incidence, 3.60; 95% CI, 1.73-7.52). Of 210 patients without ESLD randomly selected for biopsy, only 2 had cirrhosis.Conclusions: Our results indicate that although HCV infection can be self-limited or associated with ESLD, the majority of adults have persistent viremia without clinically demonstrable liver disease. Further research is needed to explain the less frequent clearance of HCV infection among black persons and to improve utilization of treatment for those infected in the context of injection drug use. JAMA. 2000;284:450-456 [ABSTRACT FROM AUTHOR]

BACKGROUND: Human immunodeficiency virus (HIV) infection adversely affects all stages of hepatitis C virus (HCV) infection, leading to increased rates of viral persistence, higher levels of HCV viremia, and accelerated progression of HCV-related liver disease. These disease interactions may result in part from impairment of B cell function, which is CD4(+) T cell dependent. METHODS: To determine the effect of HIV infection on B cell function, we compared HCV antibody levels and specificities in 29 HCV-infected persons before and after they acquired HIV and assessed the temporal correlation of these changes with overall CD4(+) T lymphocyte counts. RESULTS: The pre-HIV infection HCV antibody titer was a predictor of the subsequent titer for all antigens, and decreasing CD4(+) T cell numbers was strongly associated with a decrease in anti-HCV titers for several antigens. CD4(+) T cells counts of <500 cells/mm(3) were significantly associated with lower HCV antibody end-point titers. Higher HCV end-point titers were associated with fewer years from HIV infection and, for Core antigen, current drug use. CONCLUSIONS: HCV-specific antibody production is impaired by HIV infection, and loss of antibody production depends on CD4(+) T cell depletion. However, the decrease in titers is less significant in those who continue to actively inject drugs. Copyright © 2007 Infectious Diseases Society of America [ABSTRACT FROM AUTHOR]

The cytokine tumor necrosis factor alpha (TNF-a) is important in generating an immune response against a hepatitis C virus (HCV) infection. The functions of TNF-a may be altered by single-nucleotide polymorphisms (SNPs) in its gene, TNF. We hypothesized that SNPs in TNF may be important in determining the outcome of an HCV infection. To test this hypothesis, we typed nine TNF SNPs in a cohort of individuals with well-defined HCV outcomes. Three of these SNPs were typed in a second cohort. Data were analyzed using logistic regression stratifying by ethnicity, since rates of HCV clearance differ in black subjects versus white subjects. The SNP -863A was associated with viral clearance in black subjects (odds ratios (OR) 0.52, 95% confidence interval (CI) 0.29-0.93). Furthermore, the common wild-type haplotype -863C/-308G was associated with viral persistence in black subjects (OR 1.91, 95% CI 1.24-2.95). These findings were independent of linkage with human leukocyte antigen (HLA) alleles. Further study of this polymorphism and haplotype is needed to understand these associations and the role of TNF-a in determining outcomes of HCV infection.Genes and Immunity (2004) 5, 294-300. doi:10.1038/sj.gene.6364072 Published online 8 April 2004 [ABSTRACT FROM AUTHOR]

To test the hypothesis that person-to-person variability in blood levels of hepatitis C virus (HCV) RNA can be explained, the quantity of HCV RNA was assessed in 969 persons who acquired HCV infection in the context of injection drug use. Serum HCV RNA levels ranged from 200,000 to >120 million equivalents/mL (the linear range of the assay). The median log10 HCV RNA level was 0.46 higher in 468 human immunodeficiency virus (HIV)-positive persons than in 501 HIV-negative persons (P<.001). In addition, among HIV-negative persons, lower HCV RNA levels were independently associated with younger age (P<.001), ongoing hepatitis B infection (P=.005), and the absence of needle sharing (P=.02). However, >90% of the person-to-person HCV RNA level variability was not explained by these sociodemographic, environmental, and virologic factors. Additional research is necessary to ascertain what determines the level of HCV RNA in blood. [ABSTRACT FROM AUTHOR]

A new test that measures interferon-gamma (IFN-gamma) release in whole blood following stimulation with tuberculin has the potential to detect tuberculosis infection using a single blood draw. The IFN-gamma release assay was compared with the standard tuberculin skin test (TST) among 467 intravenous drug users at risk for tuberculosis in urban Baltimore. Among 300 human immunodeficiency virus (HIV)-seronegative patients, the IFN-gamma release assay was positive in 177 (59%), whereas the TST was positive in 71 (24%), for a percent agreement of 59% (kappa=26%). Among 167 HIV-seropositive subjects, the IFN-gamma release assay identified 32 reactors (19%); the TST identified 16 reactors (9.6%), for a percent agreement of 82% (kappa=28%). The IFN-gamma release assay detected more reactors than did the TST, but its agreement with TST was weak. As the TST is an imperfect standard, further evaluation of the IFN-gamma release assay among uninfected persons and persons with culture-confirmed tuberculosis will be useful. Copyright © 1999 The University of Chicago [ABSTRACT FROM AUTHOR]

The article examines early onset periodontal disease from a genetic perspective. The authors discuss the complexity involved with determining the etiology of early onset periodontal disease. They note that understanding the disease poses similar obstacles to those faced by geneticists studying diabetes. These obstacles include determining external triggers and susceptibility. They outline some of the factors that contribute to the difficulty faced in determining a genetic basis for the condition.

A novel, whole blood interferon-gamma (IFN-gamma) assay was evaluated to determine its suitability for detecting Mycobacterium tuberculosis exposure in intravenous drug users with or without human immunodeficiency virus (HIV) infection. Whole heparinized blood was incubated overnight in separate wells with tuberculin purified protein derivative (PPD), saline, and mitogen controls. Levels of IFN-gamma in plasma supernatants were determined by rapid ELISA. Participants were then administered the tuberculin skin test (TST) and tested for cutaneous anergy. The whole blood IFN-gamma test agreed (89%-100%) with a positive TST in both HIV-seropositive and -seronegative subjects, but reactivity to PPD was more detectable by the whole blood assay among those with negative TSTs or anergy. TST induration diameter and IFN-gamma responses were correlated (Spearman's p = .45, P = .0001), but both responses were blunted by HIV infection. In summary, tuberculin reactivity appears to be more detectable by the whole blood IFN-gamma assay than by TST, and the assay requires no return visit for test reading. [ABSTRACT FROM AUTHOR]

In a survey of 1,057 active intravenous drug users in Baltimore, MD, who were recruited through extensive community outreach, 12 reported endocarditis and 113 reported subcutaneous abscesses in the 6 months before being interviewed. Of all the persons surveyed, 556 reported cleaning their skin prior to injection at any time and 173 reported cleaning their skin all the time in the 6 months before the interview. The frequency of subcutaneous abscesses was lower among those who reported skin cleaning all the time; a similar trend was noted for frequency of endocarditis. The relatively simple procedure of encouraging intravenous drug users to clean their skin prior to injection will not eliminate but might reduce the frequency of these serious and expensive infectious complications of intravenous drug use. [ABSTRACT FROM AUTHOR]

After recovery from a hepatitis B virus (HBV) infection, reactivation can occur with immunosuppression; thus, it is assumed that replication competent HBV persists in the liver. We sought to detect persistent HBV from 13 people with spontaneous recovery. We quantified HBV DNA and RNA in core liver biopsy specimens (median, 1.72 × 106 cells) from persons who inject drugs. Of 13 biopsy specimens, 8 (61%) had evidence of HBV DNA or RNA and 5 (38%) had both HBV DNA and RNA. Messenger RNAs were derived from covalently closed circular DNA and integrated HBV DNA. Here, we show prevalent HBV DNA and RNA despite clinical recovery in persons who inject drugs., Competing Interests: Potential conflicts of interest. T. G., A. B., and C. L. T. have a patent application for the assay to determine the source of HBV transcripts used in this work. 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) 2024. Published by Oxford University Press on behalf of Infectious Diseases Society of America. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Introduction: Given structural barriers, access to services is key for preventing drug-related harms and managing chronic disease among people who inject drugs (PWID). The Patient Activation Measure (PAM), a validated scale to assess self-efficacy in navigating one's own health care, was operationalised to improve service utilisation and outcomes but has not been assessed among PWID. We characterised PAM and its association with healthcare and harm reduction utilisation among PWID in the AIDS Linked to IntraVenous Experience cohort in Baltimore., Methods: From 2019 to 2020, participants completed surveys on PAM, service utilisation and drug use. We used log-binomial regression to identify correlates of "Lower" PAM and modelled the association between lower PAM and service utilisation, stratified by recent IDU., Results: Participants (n = 351) were primarily male (67%), Black (85%) and 24% reported recent IDU. Lower PAM was significantly more common in those reporting IDU (aPR 1.45; 95% CI 1.03, 2.04), heavy alcohol (aPR 1.77; 95% CI 1.24, 2.51) and marijuana (aPR: 1.70; 95% CI 1.23, 2.36) but less common among women (aPR 0.57; 95% CI 0.38, 0.84) and those living with HIV (APR 0.52; 95% CI 0.35, 0.78). In modelling service utilisation, lower PAM was associated with a lower prevalence of methadone utilisation (aPR 0.27; 95% CI 0.09, 0.84) among those reporting IDU, but a higher prevalence of methadone utilisation (aPR 2.72; 95% CI 1.46, 5.08) among those not reporting IDU, after controlling for correlates of PAM., Discussion and Conclusion: PAM-tailored interventions targeting methadone utilisation warrant consideration but should account for socio-structural barriers to utilisation and correlates of PAM among PWID., (© 2024 Australasian Professional Society on Alcohol and other Drugs.)

Hepatitis C virus (HCV) causes substantial morbidity and mortality, particularly among people who inject drugs (PWID). While elimination of HCV as a public health problem may be possible through treatment-as-prevention, reinfection can attenuate the impact of treatment scale-up. There is a need to better understand the distribution and temporal trends in HCV infection risk, including among HCV-seropositive individuals who will be eligible for treatment and at risk for subsequent reinfection. In this analysis of 840 seronegative and seropositive PWID in Baltimore, MD USA, we used random forest methods to develop a composite risk score of HCV infection from sociodemographic and behavioural risk factors. We characterised the individual heterogeneity and temporal trajectories in this composite risk score using latent class methods and compared that index with a simpler, conventional measure, injection drug use frequency. We found that 15% of the population remained at high risk of HCV infection and reinfection by the composite metric for at least 10 years from study enrolment, while others experienced transient periods of moderate and low risk. Membership in this high-risk group was strongly associated with higher rates of HCV seroconversion and post-treatment viraemia, as a proxy of reinfection risk. Injection frequency alone was a poor measure of risk, evidenced by the weak associations between injection frequency classes and HCV-associated outcomes. Together, our results indicate HCV infection risk is not equally distributed among PWID nor well captured by injection frequency alone. HCV elimination programmes should consider targeted, multifaceted interventions among high-risk individuals to reduce reinfection., (© 2024 John Wiley & Sons Ltd.)

Background: Overdoses involving opioids and stimulants are on the rise, yet few studies have examined longitudinal trends in use of both substances. We sought to describe use and co-use of opioids and stimulants, 2005-2019, in the AIDS Linked to the Intravenous Experience (ALIVE) cohort - a community-based cohort of people with a history of injection drug use living in or near Baltimore, MD., Methods: We included 2083 ALIVE participants, who had at least two visits during the study period. Our outcome was based on self-reported use of opioids and stimulants in the prior 6 months. We estimated prevalence of 4 categories of use (neither stimulants nor opioids, only stimulants, only opioids, stimulants and opioids), using a non-parametric multi-state model, accounting for the competing event of death and weighting for informative loss to follow-up. All analyses were stratified by enrollment cohort, with the main analysis including participants who enrolled prior to 2015 and a sub-analysis including participants who enrolled 2015-2018., Results: In the main analysis, prevalence of using stimulants and opioids decreased from 38 % in 2005 to 12 % 2013 but stabilized from 2014 onwards (13-19 %). The prevalence of using only stimulants (7-11 %) and only opioids (5-10 %) was stable across time. Participants who reported using both were more likely to report homelessness, depression, and other substance use (e.g., marijuana and heavy alcohol use) than participants in the other use categories. On average, 65 % of visits with use of both were followed by a subsequent visit with use of both; of participants transitioning out of using both, 13% transitioned to using neither., Conclusions: While use of stimulants and opioids declined in the cohort through 2013, a meaningful proportion of participants persistently used both. More research is needed to understand and develop strategies to mitigate harms associated with persistent use of both stimulants and opioids., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Background: Although hepatitis C virus (HCV) can be cured by direct acting antivirals (DAA), uptake is not well characterized for people who inject drugs (PWID)., Methods: Among 1,130 participants of a community-based cohort of PWID with chronic HCV, we longitudinally characterized HCV treatment uptake and cure early (2014-2016) and later (2017-2020)., Results: Cumulative HCV treatment uptake increased from 4% in 2014 to 68% in 2020 and the percent with HCV viremia declined from nearly 100% to 33%. Predictors of treatment uptake varied across periods. Age (incidence rate ratio [IRR] per 5-year increase: 1.28; 95% confidence interval [CI]: 1.15, 1.42), educational attainment (IRR for ≥ high school diploma: 1.31; 95% CI: 1.04, 1.66), HIV coinfection with suppressed viral load (IRR vs. HIV negative: 2.08; 95% CI: 1.63, 2.66) and alcohol dependence (IRR vs. no alcohol use: 0.63; 95% CI: 0.43, 0.91) were associated with treatment uptake in the early period, but not later. HIV coinfection with a detectable viral load (IRR vs. HIV negative: 0.46; 95% CI: 0.23, 0.95) and daily injecting (IRR: 0.46 vs. no injection; 95% CI: 0.27, 0.79) were significantly associated with lower treatment uptake later. Homelessness was associated with significantly reduced likelihood of viral clearance in the late DAA era (IRR: 0.51; 95% CI: 0.30, 0.88)., Conclusion: Treatment uptake improved substantially in this cohort of PWID in the first five years of DAA availability with commensurate declines in viremia. Additional efforts are needed to treat those actively injecting and unstably housed in order to realize elimination goals., Competing Interests: Conflict of Interest DT: medical editing for UpToDate; scientific advisor to Excision Bio, Evrys Bio, and Merck. OFN research grants from Abbvie paid to institution; scientific consulting for Gilead. SM: materials support from Abbott. Other authors: no conflict declared.

We evaluated the prospective association of mitochondrial DNA copy number (mtDNA CN) with markers of kidney function among a cohort of persons who inject drugs (PWID). This is a Prospective cohort study nested in the AIDS linked to the intravenous experience cohort (community-based cohort of PWID in Baltimore, MD). mtDNA CN was measured at two time-points 5 years apart using a real-time polymerase chain reaction. Kidney function (estimated glomerular filtration rate [eGFR], serum creatinine, urine protein) was measured annually. We used linear mixed effects models to evaluate kidney function trajectories (N = 946) and Cox regression models to assess hazard of incident CKD (eGFR < 60 at two consecutive visits, N = 739) and proteinuria (urine protein:creatinine ratio > 200, N = 573) by level of mtDNA CN (Low [lowest quartile], vs high [other three quartiles]. Models were adjusted for demographic and behavioral characteristics, HIV and/or HCV infection, and comorbidity burden. Low mtDNA CN was independently associated with higher hazard of incident CKD (aHR: 2.33, 95% CI 1.42, 3.80) and proteinuria (aHR: 1.42, 95% CI 1.04, 1.96). Participants with low mtDNA CN had greater declines in eGFR and greater increases in serum creatinine over time. Low mtDNA CN is associated with more rapid kidney function decline and risk of incident CKD and proteinuria., (© 2023. The Author(s).)

We evaluated geographic heterogeneity in hepatitis C virus (HCV) treatment penetration among people who inject drug (PWID) across Baltimore, MD since the advent of direct-acting antivirals (DAAs) using space-time clusters of HCV viraemia. Using data from a community-based cohort of PWID, the AIDS Linked to the IntraVenous Experience (ALIVE) study, we identified space-time clusters with higher-than-expected rates of HCV viraemia between 2015 and 2019 using scan statistics. We used Poisson regression to identify covariates associated with HCV viraemia and used the regression-fitted values to detect adjusted space-time clusters of HCV viraemia in Baltimore city. Overall, in the cohort, HCV viraemia fell from 77% in 2015 to 64%, 49%, 39% and 36% from 2016 to 2019. In Baltimore city, the percentage of census tracts where prevalence of HCV viraemia was ≥85% dropped from 57% to 34%, 25%, 22% and 10% from 2015 to 2019. We identified two clusters of higher-than-expected HCV viraemia in the unadjusted analysis that lasted from 2015 to 2017 in East and West Baltimore and one adjusted cluster of HCV viraemia in West Baltimore from 2015 to 2016. Neither differences in age, sex, race, HIV status, nor neighbourhood deprivation were able to explain the significant space-time clusters. However, residing in a cluster with higher-than-expected viraemia was associated with age, sex, educational attainment and higher levels of neighbourhood deprivation. Nearly 4 years after DAAs became available, HCV treatment has penetrated all PWID communities across Baltimore city. While nearly all census tracts experienced improvements, change was more gradual in areas with higher levels of poverty., (© 2023 The Authors. Journal of Viral Hepatitis published by John Wiley & Sons Ltd.)