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Time‐to‐event data such as time to death are broadly used in medical research and drug development to understand the efficacy of a therapeutic. For time‐to‐event data, right censoring (data only observed up to a certain point of time) is common and easy to recognize. Methods that use right censored data, such as the Kaplan–Meier estimator and the Cox proportional hazard model, are well established. Time‐to‐event data can also be left truncated, which arises when patients are excluded from the sample because their events occur before a specific milestone, potentially resulting in an immortal time bias. For example, in a study evaluating the association between biomarker status and overall survival, patients who did not live long enough to receive a genomic test were not observed in the study. Left truncation causes selection bias and often leads to an overestimate of survival time. In this tutorial, we used a nationwide electronic health record‐derived de‐identified database to demonstrate how to analyze left truncated and right censored data without bias using example code from SAS and R. [ABSTRACT FROM AUTHOR]

Abstract Background As low and middle-income countries such as Vietnam experience the health transition from infectious to chronic diseases, the morbidity and mortality from stroke will rise. In line with the recommendation of the Institute of Medicine’s report on “Promoting Cardiovascular Health in the Developing World” to “improve local data”, we sought to investigate patient characteristics and clinical predictors of mortality among stroke inpatients at Da Nang Hospital in Vietnam. Methods A stroke registry was developed and implemented at Da Nang Hospital utilizing the World Health Organization’s Stroke STEPS instrument for data collection. Results 754 patients were hospitalized for stroke from March 2010 through February 2011 and admitted to either the intensive care unit or cardiology ward. Mean age was 65 years, and 39% were female. Nearly 50% of strokes were hemorrhagic. At 28-day follow-up, 51.0% of patients with hemorrhagic stroke died whereas 20.3% of patients with ischemic stroke died. A number of factors were independently associated with 28-day mortality; the two strongest independent predictors were depressed level of consciousness on presentation and hemorrhagic stroke type. While virtually all patients completed a CT during the admission, evidence-based processes of care such as anti-thrombotic therapy and carotid ultrasound for ischemic stroke patients were underutilized. Conclusions This cohort study highlights the high mortality due in part to the large proportion of hemorrhagic strokes in Vietnam. Lack of hypertension awareness and standards of care exacerbated clinical outcomes. Numerous opportunities for simple, inexpensive interventions to improve outcomes or reduce recurrent stroke have been identified.

Background: Neglected Tropical Diseases (NTDs) afflict around one billion individuals in the poorest parts of the world with many more at risk. Lymphatic filariasis is one of the most prevalent of the infections and causes significant morbidity in those who suffer the clinical conditions, particularly lymphedema and hydrocele. Depressive illness has been recognised as a prevalent disability in those with the disease because of the stigmatising nature of the condition. No estimates of the burden of depressive illness of any neglected tropical disease have been undertaken to date despite the recognition that such diseases have major consequences for mental health not only for patients but also their caregivers. Methods: We developed a mathematical model to calculate the burden of Disability- Adjusted Life Years (DALY) attributable to depressive illness in lymphatic filariasis and that of their caregivers using standard methods for calculating DALYs. Estimates of numbers with clinical disease was based on published estimates in 2012 and the numbers with depressive illness from the available literature. Results: We calculated that the burden of depressive illness in filariasis patients was 5.09 million disability-adjusted life years (DALYs) and 229,537 DALYs attributable to their caregivers. These figures are around twice that of 2.78 million DALYs attributed to filariasis by the Global Burden of Disease study of 2010. Conclusions: Lymphatic filariasis and other neglected tropical diseases, notably Buruli Ulcer, cutaneous leishmaniasis, leprosy, yaws, onchocerciasis and trachoma cause significant co morbidity associated with mental illness in patients. Studies to assess the prevalence of the burden of this co-morbidity should be incorporated into any future assessment of the Global Burden of neglected tropical diseases. The prevalence of depressive illness in caregivers who support those who suffer from these conditions is required. Such assessments are critical for neglected tropical diseases which have such a huge global prevalence and thus will contribute a significant burden of co-morbidity attributable to mental illness. [ABSTRACT FROM AUTHOR]

Background: Many low- to middle-income countries are faced with an increasing prevalence of overweight/ obesity while that for underweight remains high, a duality termed "double burden"; both are key risk factors for chronic diseases. This cross-sectional study assesses the prevalence and factors for underweight and overweight/ obesity among adults in Danang, Vietnam, using WHO standard and suggested Asian-specific BMI cut-offs. Methods: In 2010, 1713 residents age ≥35 years from 900 households in 6 of 56 urban, rural and mixed urban-rural communes in Danang were selected using multistage-cluster sampling methodology to participate; 1621 qualified adults enrolled. Participants completed a health survey based on WHO STEP wise Approach to Chronic Disease Risk Factor Surveillance and additional questions on chest pain and stroke symptoms. Anthropometric and other measurements were conducted. Relative risk regression was used to identify independent risk factors for underweight or overweight/obesity according to WHO standard cut-offs and suggested Asian-specific cut-offs (<18.5 kg/m² or 23-27.49 kg/m²; and ≥27.5 kg/m²). Results: We observed 12.4% prevalence of underweight and 16.0% for overweight/obesity using WHO standard. The prevalence of overweight/obesity doubled (33.7%) when Asian-specific cut-offs were applied. For both definitions, rural communes had the highest prevalence of underweight while urban communes had the highest prevalence of overweight/obesity. Being underweight was associated with less urbanization. Factors independently associated with being underweight included older age, rural living, current smoking, and lower systolic pressure. Factors independently associated with Asian-specific BMI definition for being overweight/obese included older age, urbanization, higher systolic pressure, and diabetes. Age was not an independent factor with WHO standard cut-offs; however, myocarial infarction and diabetes showed strong associations. Conclusions: The double burden of underweight and overweight/obesity observed in Danang is consistent with patterns found for large cities in Vietnam that are undergoing rapid economic growth and urbanization of lifestyle. Factors independently associated with underweight and overweight/obesity status by WHO standard and Asian-specific definitions include urbanization and modifiable lifestyle factors. Further studies are needed to define ethnic specific BMI cut-offs for Vietnam and to explore strategies to reduce the rising prevalence of overweight/ obesity. [ABSTRACT FROM AUTHOR]

Photovoice, a qualitative methodology using photography by study participants, is an ideal tool for collecting information on awareness of cardiovascular health from the perspective of persons of different cultural backgrounds and English-speaking abilities who are often subject to health disparities. Participants of Chinese, Vietnamese, and Korean ethnicity were provided disposable cameras to photograph their perceptions of scenes promoting or acting as barriers to cardiovascular health. After the pictures were developed, they returned for a discussion in their native languages to contextualize the stories told in their photographs. Group facilitators spoke the respective native languages and transcribed sessions into English. Twenty-three adults participated (7 to 9 persons per ethnicity), ranging in age from 50 to 88 (mean 71.6) years; 48% were women. The photographs stimulated conversations of knowledge, beliefs, and concerns regarding heart disease and stroke. Issues surrounding food and exercise were most dominant across ethnic groups, focusing on fat and salt intake and the need to remain active. Cultural beliefs and issues of emotional health, including stress and loneliness related to living in a new country, were also depicted. Photovoice provided insight into perceptions of cardiovascular health that is vital for developing health promotion and education interventions in limited–English-speaking communities. [ABSTRACT FROM PUBLISHER]

The article investigates the impact of premature coronary heart disease (CHD) on first-degree relatives. It indicates that first-degree relatives of people with premature CHD exhibit a risk of 2 to 12 times higher than the general population. It assesses relatives' knowledge of CHD risk factors, risk reception, and implementation of risk-reducing behaviors and their management by healthcare providers.

Objective: Perceived risk of disease plays a key role in health behaviors, making it an important issue for cancer-prevention research. We investigate associations between perceived cancer risk and selected cancer risk factors in a population-based sample of American Indians. STUDY DESIGN AND POPULATION: Data for this cross-sectional study come from a random sample of 182 American Indian adults, aged > or = 40 years, residing on the Hopi Reservation in northeastern Arizona.Outcome Measures: Perception of cancer risk was ascertained with the 5-point Likert scale question, "How likely do you think it is that you will develop cancer in the future?" dichotomized into low perceived risk and high perceived risk.Results: Participants reporting a family member with cancer were more likely, by greater than five times, to report the perception that they would get cancer (OR = 5.3; 95% CI: 2.3, 12.3). After controlling for age and family history of cancer, knowledge of cancer risk factors and attitude about cancer prevention were not significantly associated with risk perception.Conclusions: Perceived cancer risk was significantly associated with self-reported family history of cancer, supporting the importance of personal knowledge of cancer among American Indians. Further research is needed to obtain a more complete picture of the factors associated with perceptions of cancer risk among American Indians in order to develop effective interventions. [ABSTRACT FROM AUTHOR]

We tested 2655 Peruvian men who have sex with men for the presence of retroviral infection. Human T cell lymphotropic virus type 1 (HTLV-1) was detected in 48 (1.8%) of the patients, HTLV-2 was detected in 28 (1.1%), and HTLV-1 and HTLV-2 were both detected in 5 (0.2%). Human immunodeficiency virus infection was detected in 329 (12.4%) of the patients; 24 (7.3%) had HTLV coinfection. Risk factors for HTLV-1 and HTLV-2 infection varied with sexual role. [ABSTRACT FROM AUTHOR]

We investigated the risk of Parkinson's disease (PD) associated with calcium channel blockers (CCBs) and beta-blockers in a population-based case-control study of 206 men and women between ages 35 and 89 with a new diagnosis of idiopathic PD between 1992 and 2002, and 383 controls without PD or other neurodegenerative disorders who were frequency matched on age, sex, duration of GHC enrollment and clinic. The adjusted odds ratio associated with ever use was 0.85 (95% confidence interval [CI]: 0.43, 1.66) for CCBs, and 1.20 (95% CI: 0.71, 2.03) for beta-blockers. We observed no association with PD risk for either class of medication in terms of duration, dose, number of prescriptions or pattern of use. The weakness of these associations and the absence of additional influence of dose or duration of use argue against any causal interpretation. [ABSTRACT FROM AUTHOR]

Background: Birth order may play a role in autoimmune diseases and early childhood infections, both factors implicated in the etiology of narcolepsy. We investigated the association between birth order and narcolepsy risk in a population-based case-control study in which all study subjects were HLA-DQB1*0602 positive.Methods: Subjects were 18-50 years old, residents of King County, Washington, and positive for HLA-DQB1*0602. Birth order was obtained from administered interviews. We used logistic regression to generate odds ratios adjusted for income and African American race.Results: Analyses included 67 cases (mean age 34.3 [SD=9.1], 70.2% female) and 95 controls (mean age 35.1 [SD=8.8], 58.1% female). Associations for birth order were as follows: first born (cases 38.8% vs. controls 50.2%, OR=1.0; reference), second born (cases 29.9% vs. controls 32.9%, OR=1.6; 95% CI 0.7, 3.7), and third born or higher (cases 31.3% vs. controls 16.8%, OR=2.5; 95% CI 1.0, 6.0). A linear trend was significant (p<0.05). Sibling number, sibling gender, having children, and number of children did not differ significantly between narcolepsy cases and controls.Conclusions: Narcolepsy risk was significantly associated with higher birth order in this population-based study of genetically susceptible individuals. This finding supports an environmental influence on narcolepsy risk through an autoimmune mechanism, early childhood infections, or both. [ABSTRACT FROM AUTHOR]

Purpose: The utility of real-world data (RWD) for use as external controls in drug development is informed by studies that replicate trial control arms for different endpoints. The purpose of this study was to replicate control arms from four non-small cell lung cancer (NSCLC) randomized controlled trials (RCT) to analyze overall survival (OS), progression-free survival (PFS), and overall response rate (ORR) using RWD., Patients and Methods: This study used RWD from a nationwide de-identified database and a clinico-genomic database to replicate OS, PFS, and ORR endpoints in the chemotherapy control arms of four first-line NSCLC RCTs evaluating atezolizumab [IMpower150-wild-type (WT), IMpower130-WT, IMpower131, and IMpower132]. Additional objectives were to develop a definition of real-world PFS (rwPFS) and to evaluate the real-world response rate (rwRR) endpoint., Results: Baseline demographic and clinical characteristics were balanced after application of propensity score weighting methods. For rwPFS and OS, RWD external controls were generally similar to their RCT control counterparts. Across all four trials, the hazard ratio (HR) point estimates comparing trial controls with external controls were closer to 1.0 for the PFS endpoint than for the OS endpoint. An exploratory assessment of rwRR in RWD revealed a slight but nonsignificant overestimation of RCT ORR, which was unconfounded by baseline characteristics., Conclusions: RWD can be used to reasonably replicate the OS and PFS of chemotherapy control arms of first-line NSCLC RCTs. Additional studies can provide greater insight into the utility of RWD in drug development., (©2022 The Authors; Published by the American Association for Cancer Research.)

Objective: The burden of preeclampsia severity on the health of mothers and infants during the first year after delivery is unclear, given the lack of population-based longitudinal studies in the United States., Study Design: We assessed maternal and infant adverse outcomes during the first year after delivery using population-based hospital discharge information merged with vital statistics and birth certificates of 2,021,013 linked maternal-infant births in California. We calculated sampling weights using the National Center for Health Statistics data to adjust for observed differences in maternal characteristics between California and the rest of the United States. Separately, we estimated the association between preeclampsia and gestational age and examined collider bias in models of preeclampsia and maternal and infant adverse outcomes., Results: Compared with women without preeclampsia, women with mild and severe preeclampsia delivered 0.66 weeks (95% confidence interval [CI]: 0.64, 0.68) and 2.74 weeks (95% CI: 2.72, 2.77) earlier, respectively. Mild preeclampsia was associated with an increased risk of having any maternal adverse outcome (relative risk [RR] = 1.95; 95% CI: 1.93, 1.97), as was severe preeclampsia (RR = 2.80; 95% CI: 2.78, 2.82). The risk of an infant adverse outcome was increased for severe preeclampsia (RR = 2.15; 95% CI: 2.14, 2.17) but only marginally for mild preeclampsia (RR = 0.99; 95% CI: 0.98, 1). Collider bias produced an inverse association for mild preeclampsia and attenuated the association for severe preeclampsia in models for any infant adverse outcome., Conclusion: Using multiple datasets, we estimated that severe preeclampsia is associated with a higher risk of maternal and infant adverse outcomes compared with mild preeclampsia, including an earlier preterm delivery., Competing Interests: D. I. and D. P. are employees, and T. G. N. T. and W. S. are former employees of Precision Health Economics, which provides consulting and other research services to pharmaceutical, device, governmental, and nongovernmental organizations. The remaining authors report no conflict of interest., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Background: Preeclampsia is a leading cause of maternal morbidity and mortality and adverse neonatal outcomes. Little is known about the extent of the health and cost burden of preeclampsia in the United States., Objective: This study sought to quantify the annual epidemiological and health care cost burden of preeclampsia to both mothers and infants in the United States in 2012., Study Design: We used epidemiological and econometric methods to assess the annual cost of preeclampsia in the United States using a combination of population-based and administrative data sets: the National Center for Health Statistics Vital Statistics on Births, the California Perinatal Quality Care Collaborative Databases, the US Health Care Cost and Utilization Project database, and a commercial claims data set., Results: Preeclampsia increased the probability of an adverse event from 4.6% to 10.1% for mothers and from 7.8% to 15.4% for infants while lowering gestational age by 1.7 weeks (P < .001). Overall, the total cost burden of preeclampsia during the first 12 months after birth was $1.03 billion for mothers and $1.15 billion for infants. The cost burden per infant is dependent on gestational age, ranging from $150,000 at 26 weeks gestational age to $1311 at 36 weeks gestational age., Conclusion: In 2012, the cost of preeclampsia within the first 12 months of delivery was $2.18 billion in the United States ($1.03 billion for mothers and $1.15 billion for infants), and was disproportionately borne by births of low gestational age., (Copyright © 2017 Elsevier Inc. All rights reserved.)