Incidence rate of and factors associated with loss to follow-up in a longitudinal cohort of antiretroviral-treated HIV-infected persons: an AIDS Clinical Trials Group (ACTG) Longitudinal Linked Randomized Trials (ALLRT) analysis

Predictors of participant retention in a community-based HIV prevention cohort: perspectives from the HPTN 071 (PopART) study

INTRODUCTION

In 2021, there were 38.4 million people living with HIV (PLHIV) globally, of which 20.6 million (54%) were living in Eastern and Southern Africa. Longitudinal studies, inclusive of community randomized trials (CRTs), provide critical evidence to guide a broad range of health care interventions including HIV prevention. In this study, we have used an individual-level cohort study design to evaluate the association between sex and other baseline characteristics and participant retention in the HPTN 071 (PopART) trial in Zambia and South Africa.

METHODS

HPTN 071 (PopART) was a community randomized trial (CRT) conducted from 2013 to 2018, in 21 communities. The primary outcome was measured in a randomly selected population cohort (PC), followed up over 3 to 4 years at annual rounds. PC retention was defined as completion of an annual follow-up questionnaire. Baseline characteristics were described by study arm and Poisson regression analyses used to measure the association between baseline factors and retention. In addition, we present a description of researcher-documented reasons for study withdrawal by PC participants.

RESULTS

Of the 38,474 participants enrolled during the first round of the trial (PC0), most were women (27,139, 71%) and 73% completed at least one follow-up visit. Retention was lower in men (adj RR: 0.90; 95% CI: 0.88, 0.91) and higher among older participants (adj RR: 1.23; 95% CI 1.20, 1.26) when comparing ages 35-44 to 18-24 years. Retention was higher among individuals with high socioeconomic status (SES) (adj RR 1.16; 95% CI 1.14, 1.19) and medium SES (adj RR 1.12; 95% CI 1.09, 1.14) compared to low SES. The most common reasons for study withdrawal were study refusal (23%) and relocation outside the CRT catchment area (66%).

CONCLUSION

Despite challenges, satisfactory retention outcomes were achieved in PopART with limited variability across study arms. In keeping with other studies, younger age, male sex, and lower SES were associated with lower levels of retention. Relocation outside of catchment area was the most common reason for non-retention in this CRT.

Lost to follow-up in the Norwegian mother, father and child cohort study

BACKGROUND

The aim of pregnancy cohorts was to understand causes and development of health and disease throughout the life course. A major challenge in cohort studies is to avoid selection bias from loss to follow-up.

OBJECTIVE

The aim of this study was to describe what characterises drop out from the Norwegian Mother, Father and Child Cohort Study (MoBa), and provide a resource to inform the interpretation of results from analysis of cohort data.

METHODS

We estimated loss to follow-up in subsets of participants that responded to questionnaire waves in MoBa through an eight-year period and described characteristics of participants who responded to follow-ups. Within each wave of questionnaires, we estimated two exposure-outcome associations: the relationship between maternal smoking during pregnancy and offspring birthweight, and between educational level and pre-pregnancy body mass index (BMI). We explored the use of inverse probability weighting to correct the bias due to loss to follow-up.

RESULTS

Participants who continued to respond were older, higher educated, less likely to smoke and had lower BMI. We observed a decline in participation of current smokers from 22.3% to 17.5%, and participants who reported an unplanned pregnancy dropped from 19.2% to 16.4%. There was a gradual decline in the inverse relationship between maternal smoking during pregnancy and offspring birthweight with increasing follow-up information, indicating that selection bias due to drop out resulted in lower effect estimates. For the relationship between parental educational level and BMI, the inverse association increased with amount of follow-up information, indicating that the selection bias resulted in higher effect estimates. Inverse probability weighting did not completely correct the estimates for bias due to loss to follow-up.

CONCLUSIONS

Participants who remain cohort members are different from subjects who drop out. Users of large cohorts should be aware of selective loss to follow-up and consider imputation or weighting to account for loss to follow-up when analysing questionnaire responses.

Historical Benchmarks for Quality Tolerance Limits Parameters in Clinical Trials

Background

In 2016, the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use updated its efficacy guideline for good clinical practice and introduced quality tolerance limits (QTLs) as a quality control in clinical trials. Previously, TransCelerate proposed a framework for QTL implementation and parameters. Historical data can be important in helping to determine QTL thresholds in new clinical trials.

Methods

This article presents results of historical data analyses for the previously proposed parameters based on data from 294 clinical trials from seven TransCelerate member companies. The differences across therapeutic areas were assessed by comparing Alzheimer’s disease (AD) and oncology trials using a separate dataset provided by Medidata.

Results

TransCelerate member companies provided historical data on 11 QTL parameters with data sufficient for analysis for parameters. The distribution of values was similar for most parameters with a relatively small number of outlying trials with high parameter values. Medidata provided values for three parameters in a total of 45 AD and oncology trials with no obvious differences between the therapeutic areas.

Conclusion

Historical parameter values can provide helpful benchmark information for quality control activities in future trials.

Prospective assessment of loss to follow-up: incidence and associated factors in a cohort of HIV-positive adults in rural Tanzania

Introduction

Lifelong antiretroviral therapy (ART) improves health outcomes for HIV‐positive individuals, but is jeopardized by irregular clinic attendance and hence poor adherence. Loss to follow‐up (LTFU) is typically defined retrospectively but this may lead to biased inferences. We assessed incidence of and factors associated with LTFU, prospectively and accounting for recurrent LTFU episodes, in the Kilombero and Ulanga Antiretroviral Cohort (KIULARCO) of HIV‐positive persons in rural Tanzania.

Methods

We included adults (≥15 years) enrolled in 2005 to 2016, regardless of ART status, with follow‐up through April 2017. LTFU was defined as >60 days late for a scheduled appointment. Participants could experience multiple LTFU episodes. We performed analyses based on the first (prospective) and last (retrospective) events observed during follow‐up, and accounting for recurrent LTFU episodes. Time to LTFU was estimated using cumulative incidence functions. We assessed factors associated with LTFU using cause‐specific proportional hazards, marginal means/rates, and Prentice, Williams and Peterson models.

Results

Among 8087 participants (65% female, 60% aged ≥35 years, 42% WHO stage 3/4, and 47% CD4 count <200 cells/mm³), there were 8140 LTFU episodes, after which there were 2483 (31%) returns to care. One‐year LTFU probabilities were 0.41 (95% confidence interval 0.40, 0.42) and 0.21 (0.20, 0.22) considering the first and last events respectively. Factors associated with LTFU were broadly consistent across different models: being male, younger age, never married, living far from the clinic, not having an HIV‐positive partner, lower BMI, advanced WHO stage, not having tuberculosis, and shorter time since ART initiation. Associations between LTFU and pregnancy, CD4 count, and enrolment year depended on the analysis approach.

Conclusions

LTFU episodes were common and prompt tracing efforts are urgently needed. We identified socio‐demographic and clinical characteristics associated with LTFU that can be used to target tracing efforts and to help inform the design of appropriate interventions. Incidence of and risk factors for LTFU differed based on the LTFU definition applied, highlighting the importance of appropriately accounting for recurrent LTFU episodes. We recommend using a prospective definition of LTFU combined with recurrent event analyses in cohorts where repeated interruptions in care are common.

Frailty, Neurocognitive Impairment, or Both in Predicting Poor Health Outcomes Among Adults Living With Human Immunodeficiency Virus

Background

Neurocognitive impairment (NCI) is strongly associated with frailty in people living with human immunodeficiency virus (PLWH); the overlap of frailty and NCI and the impact on health outcomes in PLWH are unknown.

Methods

PLWH in a longitudinal, observational study of aging completed entry evaluations for frailty and NCI. Outcomes of falls (recurrent) increased limitations in independent activities of daily living (IADL), or mortality were combined. Poisson regression models estimated prevalence ratios (PR) for ≥1 outcome over 2 years.

Results

Among 987 participants, the median age at entry was 51 years; 19% were female; the median CD4 count was 616 cells/µL; and HIV-1 RNA was <200 copies/mL in 94%. Most (79%) participants had neither frailty nor NCI; 2% had both; 4% frailty only; and 15% NCI only. Over 2 years of observation, 100 (10%) participants experienced recurrent falls; 175 (18%) had worsening IADL limitations; 17 (2%) died; and 254 (26%) experienced ≥1 poor health outcome. In adjusted models, frailty with NCI was associated with more than double the risk of a poor health outcome (PR 2.65; 95% CI 1.98, 3.54); a significant association was also seen with frailty alone (PR 2.26; 95%CI 1.71, 2.99) and NCI alone (PR 1.73; 95% CI 1.36, 2.20).

Conclusions

The presence of frailty with NCI was associated with a greater risk of falls, disability, or death in PLWH than NCI alone. Interventions that target prevention or reversal of both frailty and NCI (such as increased physical activity) may significantly limit poor health outcomes among PLWH.

Improvements in the HIV care continuum needed to meaningfully reduce HIV incidence among men who have sex with men in Baltimore, US: a modelling study for HPTN 078

INTRODUCTION

HIV prevalence is high among men who have sex with men (MSM) in Baltimore, Maryland, United States, and the levels of viral suppression among HIV-positive MSM are relatively low. The HIV Prevention Trials Network 078 trial seeks to increase the levels of viral suppression among US MSM by increasing the rates of diagnosis and linkage to care and treatment. We estimated the increases in viral suppression needed to reach different HIV incidence reduction targets, and the impact of meeting diagnosis and treatment targets.

METHODS

We used a mathematical model of HIV transmission among MSM from Baltimore, US, parameterised with behavioural data and fitted to HIV prevalence and care continuum data for Baltimore wherever possible, to project increases in viral suppression needed to reduce the HIV incidence rate among Baltimore MSM by 10, 20, 30 or 50% after 2, 5 and 10 years. We also projected HIV incidence reductions achieved if US national targets - 90% of people living with HIV (PLHIV) know their HIV serostatus, 90% of those diagnosed are retained in HIV medical care and 80% of those diagnosed are virally suppressed - or UNAIDS 90-90-90 targets (90% of PLHIV know their status, 90% of those diagnosed receive antiretroviral therapy (ART), 90% of those receiving ART are virally suppressed) are each met by 2020.

RESULTS

To reduce the HIV incidence rate by 20% and 50% after five years (compared with the base-case at the same time point), the proportion of all HIV-positive MSM who are virally suppressed must increase above 2015 levels by a median 13 percentage points (95% uncertainty interval 9 to 16 percentage points) from median 49% to 60%, and 27 percentage points (22 to 35) from 49% to 75% respectively. Meeting all three US or 90-90-90 UNAIDS targets results in a 48% (31% to 63%) and 51% (38% to 65%) HIV incidence rate reduction in 2020 respectively.

CONCLUSIONS

Substantial improvements in levels of viral suppression will be needed to achieve significant incidence reductions among MSM in Baltimore, and to meet 2020 US and UNAIDS targets. Future modelling studies should additionally consider the impact of pre-exposure prophylaxis for MSM.

Stroke incidence is highest in women and non-Hispanic blacks living with HIV in the AIDS Clinical Trials Group Longitudinal Linked Randomized Trials cohort

OBJECTIVE

To investigate the incidence of first-ever stroke/transient ischemic attack (TIA) and associated risk factors in a cohort of persons living with HIV infection (PLWH).

DESIGN

Observational cohort study

METHODS

We determined incidence rates of first-ever stroke/TIA in PLWH after ART initiation from the AIDS Clinical Trials Group ALLRT cohort and its parent trials. Poisson regression models evaluated baseline and time-varying covariates as risk factors for stroke/TIA.

RESULTS

The incidence rate of stroke/TIA was 1.69 per 1000 person-years. Incidence rates were highest in women (2.88 stroke/TIAs per 1000 person-years compared with 1.40 per 1000 person-years in men) and non-Hispanic Blacks (2.51 stroke/TIAs per 1000 person-years compared with 0.77 per 1000 person-years in Hispanic/other race/ethnicities and 1.56 per 1000 person-years in whites). In a multivariable model, we found a significant age-by-sex interaction (P = 0.01). The higher risk of stroke/TIA in women was more pronounced at younger ages, whereas older age conferred a greater increase in stroke/TIA risk in men than women. Other risk factors for stroke/TIA included hypertension, higher LDL, and HIV RNA greater than 200 copies/ml. Overweight/obese BMI and higher CD4+:CD8+ ratio protected against stroke/TIA.

CONCLUSION

Women and non-Hispanic Blacks living with HIV had the highest incidence rates of stroke/TIA. A concerted effort must be made to include PLWH from these at-risk groups in observational and interventional studies aimed at understanding stroke mechanisms and reducing stroke risk in HIV infection. Strategies to modify stroke risk in PLWH should employ a multipronged approach targeting vascular risk factors and engaging and retaining patients in HIV care.

Estimation of the cumulative incidence function under multiple dependent and independent censoring mechanisms

Competing risks occur in a time-to-event analysis in which a patient can experience one of several types of events. Traditional methods for handling competing risks data presuppose one censoring process, which is assumed to be independent. In a controlled clinical trial, censoring can occur for several reasons: some independent, others dependent. We propose an estimator of the cumulative incidence function in the presence of both independent and dependent censoring mechanisms. We rely on semi-parametric theory to derive an augmented inverse probability of censoring weighted (AIPCW) estimator. We demonstrate the efficiency gained when using the AIPCW estimator compared to a non-augmented estimator via simulations. We then apply our method to evaluate the safety and efficacy of three anti-HIV regimens in a randomized trial conducted by the AIDS Clinical Trial Group, ACTG A5095.

Recruiting a representative sample in adherence research-The MALT multisite prospective cohort study experience

Medication adherence is an important determinant of transplant outcomes. Attempts to investigate adherence are frequently undermined by selection bias: It is very hard to recruit and retain non-adherent patients in research efforts. This manuscript presents recruitment strategies and results from the MALT (Medication Adherence in children who had a Liver Transplant) multisite prospective cohort study. MALT sites recruited 400 pediatric liver transplant patients who agreed to be followed for 2 years. The primary purpose was to determine whether a marker of adherence, the Medication Level Variability Index (MLVI), predicts rejection outcomes. The present manuscript describes methods used in MALT to ensure that a representative sample was recruited, and presents detailed recruitment results. MALT sites were able to recruit a nationally representative sample, as determined by a comparison between the MALT cohort and a national sample of transplant recipients. Strategies that helped ensure that the sample was representative included monitoring of the outcome measure in comparison with a national sample, drastically limiting patient burden, and specific recruitment methods. We discuss the importance of a representative sample in adherence research and recommend that future efforts to study adherence pay special attention to sample characteristics.

The Raine study had no evidence of significant perinatal selection bias after two decades of follow up: a longitudinal pregnancy cohort study

BACKGROUND

Cohort studies may increase or decrease their selection bias as they progress through time. The Western Australian Pregnancy Cohort (Raine) Study has followed 2868 children for over two decades; from fetal into adult life. This paper analyses the cohort over time, assessing potential bias that may come and go with recruitment, retention and loss of participants.

METHODS

Linked data from all births in Western Australian over the 3 years the Raine Cohort was recruited were obtained to compare perinatal characteristics and subsequent health outcomes between the Western Australian (WA) contemporaneous birth population and the Raine Cohort at five time points. Perinatal exposure-outcome comparisons were employed to assess bias due to non-participation in Raine Study subsets.

RESULTS

There were demographic differences between the Raine Study cohort and its source population at recruitment with further changes across the period of follow up. Despite these differences, the pregnancy and infant data of those with continuing participation were not significantly different to the WA contemporaneous birth population. None of the exposure-outcome associations were significantly different to those in the WA general population at recruitment or at any cohort reviews suggesting no substantial recruitment or attrition bias.

CONCLUSIONS

The Raine Study is valuable for association studies, even after 20 years of cohort reviews with increasing non-participation of cohort members. Non-participation has resulted in greater attrition of socially disadvantaged participants, however, exposure-outcome association analyses suggest that there is no apparent resulting selection bias.

Using lean manufacturing principles to evaluate wait times for HIV-positive patients in an urban clinic in Kenya

As human immunodeficiency virus (HIV) treatment programs expand in Africa, delivery systems must be strengthened to support patient retention. Clinic characteristics may affect retention, but a relationship between clinic flow and attrition is not established. This project characterized HIV patient experience and flow in an urban Kenyan clinic to understand how these may affect retention. We used Toyota's lean manufacturing principles to guide data collection and analysis. Clinic flow was evaluated using value stream mapping and time and motion techniques. Clinic register data were analyzed. Two focus group discussions were held to characterize HIV patient experience. Results were shared with clinic staff. Wait times in the clinic were highly variable. We identified four main barriers to patient flow: inconsistent patient arrivals, inconsistent staffing, filing system defects, and serving patients out of order. Focus group participants explained how clinic operations affected their ability to engage in care. Clinic staff were eager to discuss the problems identified and identified numerous low-cost potential solutions. Lean manufacturing methodologies can guide efficiency interventions in low-resource healthcare settings. Using lean techniques, we identified bottlenecks to clinic flow and low-cost solutions to improve wait times. Improving flow may result in increased patient satisfaction and retention.

Describing Point of Entry into Care and Being Lost to Program in a Cohort of HIV Positive Pregnant Women in a Large Urban Centre in Uganda

Introduction. We aim to describe the time of entry into care and factors associated with being lost to program (LTP) in pregnant women on Option B Plus in an integrated HIV and antenatal care (ANC) clinic in Uganda. Methods. We included all pregnant women enrolled into the integrated HIV-ANC clinic from January 2012 to 31st July 2014, while the follow up period extended up to October 30th 2015. LTP was defined as being out of care for ≥3 months. Results. Overall 856 women were included. Only 36.4% (86/236) of the women were enrolled in the first trimester. Overall 69 (8.1%) were LTP. In the multivariate analysis older women (HR: 0.80 per five-year increase, CI: 0.64-1.0, and P = 0.060) and women on ART at the time of pregnancy (0.58, CI: 0.34-0.98, and P = 0.040) were more likely not to be LTP. Among women already on ART at the time of pregnancy no factor was associated with LTP. Conclusion. Our results suggest the need for interventions to enhance prompt linkage of HIV positive women to HIV services for ART initiation and for increased retention particularly in young and ART naive women.

Sex, Race, and HIV Risk Disparities in Discontinuity of HIV Care After Antiretroviral Therapy Initiation in the United States and Canada

Disruption of continuous retention in care (discontinuity) is associated with HIV disease progression. We examined sex, race, and HIV risk disparities in discontinuity after antiretroviral therapy (ART) initiation among patients in North America. Adults (≥18 years of age) initiating ART from 2000 to 2010 were included. Discontinuity was defined as first disruption of continuous retention (≥2 visits separated by >90 days in the calendar year). Relative hazard ratio (HR) and times from ART initiation until discontinuity by race, sex, and HIV risk were assessed by modeling of the cumulative incidence function (CIF) in the presence of the competing risk of death. Models were adjusted for cohort site, baseline age, and CD4+ cell count within 1 year before ART initiation; nadir CD4+ cell count after ART, but before a study event, was assessed as a mediator. Among 17,171 adults initiating ART, median follow-up time was 3.97 years, and 49% were observed to have ≥1 discontinuity of care. In adjusted regression models, the hazard of discontinuity for patients was lower for females versus males [HR: 0.84; 95% confidence interval (CI): 0.79-0.89] and higher for blacks versus nonblacks (HR: 1.17; 95% CI: 1.12-1.23) and persons with injection drug use (IDU) versus non-IDU risk (HR: 1.33; 95% CI: 1.25-1.41). Sex, racial, and HIV risk differences in clinical retention exist, even accounting for access to care and known competing risks for discontinuity. These results point to vulnerable populations at greatest risk for discontinuity in need of improved outreach to prevent disruptions of HIV care.

Sociodemographic profile and predictors of outpatient clinic attendance among HIV-positive patients initiating antiretroviral therapy in Selangor, Malaysia

BACKGROUND

Inconsistent literature evidence suggests that sociodemographic, economic, and system- and patient-related factors are associated with clinic attendance among the HIV-positive population receiving antiretroviral therapy (ART) around the world. We examined the factors that predict outpatient clinic attendance among a cohort of HIV-positive patients initiating ART in Selangor, Malaysia.

PATIENTS AND METHODS

This cross-sectional study analyzed secondary data on outpatient clinic attendance and sociodemographic, economic, psychosocial, and patient-related factors among 242 adult Malaysian patients initiating ART in Selangor, Malaysia. Study cohort was enrolled in a parent randomized controlled trial (RCT) in Hospital Sungai Buloh Malaysia between January and December 2014, during which peer counseling, medication, and clinic appointment reminders were provided to the intervention group through short message service (SMS) and telephone calls for 24 consecutive weeks. Data on outpatient clinic attendance were extracted from the hospital electronic medical records system, while other patient-level data were extracted from pre-validated Adult AIDS Clinical Trial Group (AACTG) adherence questionnaires in which primary data were collected. Outpatient clinic attendance was categorized into binary outcome - regular attendee and defaulter categories - based on the number of missed scheduled outpatient clinic appointments within a 6-month period. Multivariate regression models were fitted to examine predictors of outpatient clinic attendance using SPSS version 22 and R software.

RESULTS

A total of 224 (93%) patients who completed 6-month assessment were included in the model. Out of those, 42 (18.7%) defaulted scheduled clinic attendance at least once. Missed appointments were significantly more prevalent among females (n=10, 37.0%), rural residents (n=10, 38.5%), and bisexual respondents (n=8, 47.1%). Multivariate binary logistic regression analysis showed that Indian ethnicity (adjusted odds ratio [AOR] =0.235; 95% CI [0.063-0.869]; P=0.030) and heterosexual orientation (AOR =4.199; 95% CI [1.040-16.957]; P=0.044) were significant predictors of outpatient clinic attendance among HIV-positive patients receiving ART in Malaysia.

CONCLUSION

Ethnicity and sexual orientation of Malaysian patients may play a significant role in their level of adherence to scheduled clinic appointments. These factors should be considered during collaborative adherence strategy planning at ART initiation.

Risk factors in an HIV-infected population for refraining from specialist care

BACKGROUND

To obtain maximal benefit of combination antiretroviral therapy (cART), HIV-infected patients should be retained in medical care. Missed clinical visits are independently associated with all-cause mortality among HIV-infected patients. Our objective was to identify risk factors and patient-reported reasons for nonattendance at outpatient clinic appointments.

DESIGN AND METHODS

We conducted a cross-sectional case-control study among 447 HIV-infected patients attending the outpatient clinic between March and July 2014. Patients with missed appointments from January 2013 onwards were included as cases and compared to a random selection of same-day controls without missed appointments during the same period. Clinical and socio-demographic characteristics were collected from clinical records and an interviewer-administered questionnaire. Additionally, reasons for nonattendance and possible solutions for future better attendance were addressed in the questionnaire. Multivariable logistic regression analysis was used to determine independent risk factors for nonattendance.

RESULTS

A total of 224 cases and 223 controls were included. Independent risk factors for nonattendance were: (i) age <30 years (odds ratio (OR) 7.2; 95% CI: 3.2-16.3 versus ≥50 years); (ii) African region of origin (OR 2.8; 95% CI: 1.5-5.0 versus Western origin); (iii) having children <12 years of age (OR 2.1; 95% CI: 1.1-4.1); (iv) history of drugs- or alcohol abuse (OR 4.4; 95% CI: 1.8-10.8); (v) no cART (OR 2.5; 95% CI: 1.1-5.3) or HIV-RNA >400 copies/ml while receiving cART (OR 3.5; 95% CI: 1.3-9.6). The main reason given for nonattendance was failure to remember the appointments (44%). Most patients would prefer to receive an appointment reminder by SMS (80% of the cases and 55% of the controls).

CONCLUSION

Missing outpatient clinic appointments were associated with available clinical characteristics. Nonattendance may be prevented by sending routine SMS reminders prior to the next appointment.

Predictors of Poor Retention in Care of HIV-infected Patients Receiving Antiretroviral Therapy in Korea: Five-Year Hospital-based Retrospective Cohort Study

Poor retention in care (RIC) is associated with higher antiretroviral therapy (ART) failure and worse survival. Identifying high risk patients for poor RIC is important for targeted intervention. A retrospective cohort study was conducted at a tertiary care hospital in Korea. HIV-infected patients initiating ART during 2002-2008 were included. 5 year-RIC was measured by hospital visit constancy (HVC) at 5 years after initiating ART. Among 247 enrolled patients, 179 (72.5%) remained in care, 20 (8.1%) were transferred to other hospitals, 9 (3.6%) died and 39 (15.8%) were lost to follow-up. We compared the demographic, psychosocial, and clinical characteristics between the groups with 100% HVC (n = 166, 67.2%) and ≤ 50% HVC (n = 33, 13.4%). In multivariable analysis, ART-starting age ≤ 30 years (odds ratio [OR] 4.08 vs. > 50; 95% confidence interval [CI] 1.10-15.15, P = 0.036), no non-HIV related comorbidity (OR 2.94 vs. comorbidity ≥ 1; 95% CI 1.02-8.49, P = 0.046), baseline CD4 cell count > 300 cells/μL (OR 3.58 vs. ≤ 200; 95% CI 1.33-9.65, P = 0.012) were significant predictable factors of poor RIC. HIV/AIDS care-givers should pay attention to young patients with higher baseline CD4 cell counts and no non-HIV related comorbidity.

Evaluating predictors of competing risk outcomes when censoring depends on time-dependent covariates, with application to safety and efficacy of HIV treatment

We propose a prediction model for the cumulative incidence functions of competing risks, based on a logit link. Because of a concern about censoring potentially depending on time-varying covariates in our motivating human immunodeficiency virus (HIV) application, we describe an approach for estimating the parameters in the prediction models using inverse probability of censoring weighting under a missingness at random assumption. We then illustrate the application of this methodology to identify predictors of the competing outcomes of virologic failure, an efficacy outcome, and treatment limiting adverse event, a safety outcome, among human immunodeficiency virus-infected patients first starting antiretroviral treatment. Copyright © 2016 John Wiley & Sons, Ltd.

Different factors associated with loss to follow-up of infants born to HIV-infected or uninfected mothers: observations from the ANRS 12140-PEDIACAM study in Cameroon

Background

Loss to follow-up (LTFU) is a cause of potential bias in clinical studies. Differing LTFU between study groups may affect internal validity and generalizability of the results. Understanding reasons for LTFU could help improve follow-up in clinical studies and thereby contribute to goals for prevention, treatment, or research being achieved. We explored factors associated with LTFU of mother-child pairs after inclusion in the ANRS 12140-Pediacam study.

Methods

From November 2007 to October 2010, 4104 infants including 2053 born to HIV-infected mothers and 2051 born to HIV-uninfected mothers matched individually on gender and study site were enrolled during the first week of life in three referral hospitals in Cameroon and scheduled for visits at 6, 10 and 14 weeks of age. Visits were designated 1, 2 and 3, in chronological order, irrespective of the child’s age at the time of the visit. Mother-child pairs were considered lost to follow-up if they never returned for a clinical visit within the first six months after inclusion. Uni- and multivariable logistic regression were adjusted on matching variables to identify factors associated with LTFU according to maternal HIV status.

Results

LTFU among HIV-unexposed infants was four times higher than among HIV-exposed infants (36.7% vs 9.8%, p < 0.001). Emergency caesarean section (adjusted Odds Ratio (aOR) = 2.46 95% Confidence Interval (CI) [1.47-4.13]), young maternal age (aOR = 2.29, 95% CI [1.18-4.46]), and absence of antiretroviral treatment for prophylaxis (aOR = 3.45, 95% CI [2.30-5.19]) were independently associated with LTFU among HIV-exposed infants. Factors associated with LTFU among HIV-unexposed infants included young maternal age (aOR = 1.96, 95% CI [1.36-2.81]), low maternal education level (aOR = 2.77, 95% CI [1.95-3.95]) and housewife/unemployed mothers (aOR = 1.56, 95% CI [1.16-2.11]).

Conclusion

Failure to return for at least one scheduled clinical visit is a problem especially among HIV-unexposed infants included in studies involving HIV-exposed infants. Factors associated with this type of LTFU included maternal characteristics, socio-economic status, quality of antenatal care and obstetrical context of delivery. Enhanced counselling in antenatal and intrapartum services is required for mothers at high risk of failure to return for follow-up visits.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-1555-2) contains supplementary material, which is available to authorized users.

Retention of black and white participants in the selenium and vitamin E cancer prevention trial (SWOG-coordinated intergroup study S0000)

BACKGROUND

Disproportionally low retention of minority populations can adversely affect the generalizability of clinical research trials. We determine the overall retention rates for White and Black participants from the Selenium and Vitamin E Cancer Prevention Trial (SELECT) and explore participant and site characteristics associated with retention failure (study disengagement) for these groups.

METHODS

A secondary analysis of 28,118 White (age ≥55), and 4,322 Black (age ≥ 50) SELECT participants used multivariate Cox regression to estimate overall retention rates and to calculate HRs and 95% confidence intervals (CI).

RESULTS

Blacks had higher age-adjusted risk of disengagement than Whites (HR, 1.92; 95% CI, 1.77-2.08). Among Black participants, those ages 50 to 54 were at three times the risk of disengagement than those ≥65 years of age (HR, 3.61; 95% CI, 2.41-5.41). Blacks age ≥65 had 1.6 times the risk of disengagement than Whites age ≥65 (HR, 1.60; 95% CI, 1.38-1.87). By 6 years after randomization, 84% of Whites and 69% of Blacks remained engaged in the study. Current smoking status was an independent risk factor for study disengagement for both White and Black participants. For both groups, sites whose staffs missed SELECT training sessions or who received SELECT Retention and Adherence grants were associated with increased and decreased disengagement risks, respectively.

CONCLUSIONS

SELECT retention was disproportionately lower for Blacks than for Whites.

IMPACT

The observed difference in retention rates for Blacks and Whites and factors identified by race for study disengagement in SELECT may inform retention efforts for future long-term, cancer prevention trials.

Factors associated with study attrition among HIV-infected risky drinkers in St. Petersburg, Russia

BACKGROUND

Participant attrition in HIV longitudinal studies may introduce bias and diminish research quality. The identification of participant characteristics that are predictive of attrition might inform retention strategies.

OBJECTIVE

The study aimed to identify factors associated with attrition among HIV-infected Russian risky drinkers from the secondary HIV prevention HERMITAGE trial. We examined whether current injection drug use (IDU), binge drinking, depressive symptoms, HIV status nondisclosure, stigma, and lifetime history of incarceration were predictors of study attrition. We also explored effect modification due to gender.

METHODS

Complete loss to follow-up (LTFU), defined as no follow-up visits after baseline, was the primary outcome, and time to first missed visit was the secondary outcome. We used multiple logistic regression models for the primary analysis, and Cox proportional hazards models for the secondary analysis.

RESULTS

Of 660 participants, 101 (15.3%) did not return after baseline. No significant associations between independent variables and complete LTFU were observed. Current IDU and HIV status nondisclosure were significantly associated with time to first missed visit (adjusted hazard ratio [AHR], 1.39; 95% CI, 1.03-1.87; AHR, 1.38; 95% CI, 1.03-1.86, respectively). Gender stratified analyses suggested a larger impact of binge drinking among men and history of incarceration among women with time to first missed visit.

CONCLUSIONS

Although no factors were significantly associated with complete LTFU, current IDU and HIV status nondisclosure were significantly associated with time to first missed visit in HIV-infected Russian risky drinkers. An understanding of these predictors may inform retention efforts in longitudinal studies.

Time-Dependent Predictors of Loss to Follow-Up in a Large HIV Treatment Cohort in Nigeria

Evaluation of time-dependent predictors of loss to follow-up in a large HIV treatment program revealed that early adherence patterns, in addition to CD4 count and viral load, predicted loss to follow-up and should be used as measures in devising targeted interventions to increase program retention.

Background

 Most evaluations of loss to follow-up (LTFU) in human immunodeficiency virus (HIV) treatment programs focus on baseline predictors, prior to antiretroviral therapy (ART) initiation. As risk of LTFU is a continuous issue, the aim of this evaluation was to augment existing information with further examination of time-dependent predictors of loss.

Methods

 This was a retrospective evaluation of data collected between 2004 and 2012 by the Harvard School of Public Health and the AIDS Prevention Initiative in Nigeria as part of PEPFAR-funded program in Nigeria. We used multivariate modeling methods to examine associations between CD4⁺ cell counts, viral load, and early adherence patterns with LTFU, defined as no refills collected for at least 2 months since the last scheduled appointment.

Results

 Of 51 953 patients initiated on ART between 2004 and 2011, 14 626 (28%) were LTFU by 2012. Factors associated with increased risk for LTFU were young age, having nonincome-generating occupations or no education, being unmarried, World Health Organization (WHO) stage, having a detectable viral load, and lower CD4⁺ cell counts. In a subset analysis, adherence patterns during the first 3 months of ART were associated with risk of LTFU by month 12.

Conclusions

 In settings with limited resources, early adherence patterns, as well as CD4⁺ cell counts and unsuppressed viral load, at any time point in treatment are predictive of loss and serve as effective markers for developing targeted interventions to reduce rates of attrition.

Predictors of non-adherence to clinical follow-up among patients participating in a randomized trial of pharmaceutical care intervention in HIV-positive adults in Southern Brazil

Pharmaceutical care (PC) has been shown to improve adherence to therapeutic interventions as well as improve clinical outcomes. We assessed the predictors of non-adherence to clinical follow-up (i.e., not attending three scheduled routine clinical visits over a 1 year period) among patients who participated in a clinical trial of PC intervention on adherence to HIV antiretroviral therapy uptake (the PC-HIV trial). A total of 332 patients participated: median age was 39 years, 63 % were male, 76 % had CD4 count ≥200 cells/mm³, and 52 % had undetectable viral load. About half, 52.7 %, were non-adherent to clinical follow-up. Identified risk factors for non-adherence were male gender, age <40 years, and being in the trial's "control" group (adjusted odds ratio [AOR] 1.67, 95 % CI 1.05-2.66; AOR 2.21, 95 % CI 1.42-3.47; AOR 1.67, 95 % CI 1.07-2.61, respectively). Younger, male patients may benefit from interventions such as PC, which facilitates engagement in care.

Plasma apolipoprotein L1 levels do not correlate with CKD

Polymorphisms in APOL1 are associated with CKD, including HIV-related CKD, in individuals of African ancestry. The apolipoprotein L1 (APOL1) protein circulates and is localized in kidney cells, but the contribution of APOL1 location to CKD pathogenesis is unclear. We examined associations of plasma APOL1 levels with plasma cytokine levels, dyslipidemia, and APOL1 genotype in a nested case-control study (n=270) of HIV-infected African Americans enrolled in a multicenter prospective observational study. Patients were designated as having CKD when estimated GFR (eGFR) decreased to <60 ml/min per 1.73 m(2) (eGFR<60 cohort) or protein-to-creatinine ratios became >3.5 g/g (nephrotic proteinuria cohort). Circulating APOL1 levels did not associate with APOL1 genotype, CKD status, or levels of proinflammatory cytokines, but did correlate with fasting cholesterol, LDL cholesterol, and triglyceride levels. At ascertainment, CKD-associated polymorphisms (risk variants) in APOL1 associated with the eGFR<60 cohort, but not the nephrotic-range proteinuria cohort. Of note, in both the eGFR<60 and nephrotic proteinuria cohorts, CKD cases with two APOL1 risk variants had significant declines in eGFR over a median of 4 years compared with individuals with one or no risk variants. APOL1 risk genotype was not associated with changes in proteinuria. Higher circulating proinflammatory cytokine levels were independently associated with CKD but not APOL1 genotype. In conclusion, the function of variant APOL1 proteins derived from circulation or synthesized in the kidney, but not the level of circulating APOL1, probably mediates APOL1-associated kidney disease in HIV-infected African Americans.

Impact of definitions of loss to follow-up on estimates of retention, disease progression, and mortality: application to an HIV program in Mozambique

Patient retention is critical to the management of chronic diseases such as human immunodeficiency virus (HIV); hence, accurate measures of loss to follow-up (LTF) are important. Many different LTF definitions have been proposed. In a cohort of 9,692 HIV-infected patients initiating antiretroviral therapy in Mozambique from 2006 to 2011, we investigated the impact of the definition of LTF on estimated rates of LTF, acquired immunodeficiency syndrome (AIDS)-defining events, and death by applying 17 different definitions of LTF gleaned from HIV literature. We further investigated the impact of 4 specific components of the LTF definitions. Cumulative incidences of LTF and AIDS-defining events were estimated by treating death as a competing risk; Kaplan-Meier techniques and variations to account for informative censoring were used to estimate rates of mortality. Estimates of LTF 2 years after treatment initiation were high and varied substantially, from 22% to 84% depending on the LTF definition used. Estimates of 2-year mortality varied from 11% to 16%, and estimates of 2-year AIDS-defining events varied from 6% to 8%. As seen here, the choice of LTF definition can greatly affect study conclusions and program evaluations. Selection of LTF definitions should be based on the study outcome, available data on clinical encounters, and the patients' visit schedules; we suggest some general guidelines.

The impact of age on the prognostic capacity of CD8+ T-cell activation during suppressive antiretroviral therapy

OBJECTIVE

To assess whether CD8 T-cell activation predicts risk of AIDS and non-AIDS morbidity during suppressive antiretroviral treatment (ART).

DESIGN

Post-hoc analyses of ART-naive participants in prospective ART studies. Participants with HIV-RNA levels 200 copies/ml or less and CD8 T-cell activation data (%CD38HLA-DR) at year-1 of ART were selected to determine years 2-5 incidence of AIDS and non-AIDS events.

METHODS

We censored data at time of ART interruption or virologic failure. Inverse probability of censoring-weighted logistic regression was used to correct for informative censoring.

RESULTS

We included 1025 participants; 82% were men, median age 38 years, pre-ART CD4 cell count 255 cells/μl, and year-1-activated CD8 T cells 24%. Of these, 752 had 5 years of follow-up; 379 remained on ART and had no confirmed plasma HIV-RNA more than 200 copies/ml. The overall probability of an AIDS or non-AIDS event in years 2-5 was estimated at 13% [95% confidence interval (CI) 10-15%] had everyone remained on suppressive ART. Higher year-1-activated CD8 T-cell percentage increased the probability of subsequent events [odds ratio 1.22 per 10% higher (95% CI 1.04-1.44)]; this effect was not significant after adjusting for age. Among those age 50 years at least (n=108 at year 1), the probability of an event in years 2-5 was 37% and the effect of CD8 T-cell activation was more apparent (odds ratio=1.42, P=0.02 unadjusted and adjusted for age).

CONCLUSION

CD8 T-cell activation is prognostic of clinical events during suppressive ART, although this association is confounded by age. The consequences of HIV-associated immune activation may be more important in patients 50 years and older.

High retention among HIV-infected children in Rwanda during scale-up and decentralization of HIV care and treatment programs, 2004 to 2010

BACKGROUND

Efforts to scale-up HIV treatment in high burden countries have resulted in wider access to care, improved survival and decreased morbidity for HIV-infected children. The country of Rwanda has made significant achievements in expanding coverage of pediatric HIV services.

METHODS

We describe the extent of and factors associated with mortality and lost to follow-up (LTF) in children (<15 years) enrolled in HIV care at 39 ICAP-supported facilities across Rwanda from 2004 to 2010 by antiretroviral treatment (ART) status. We estimated the 1-year cumulative incidence of death and LTF among all children enrolled in care (pre-ART) and children on ART. Survival analysis was used to evaluate factors associated with death and LTF in both groups.

RESULTS

Between January 2004 and June 2010, 3244 children with a median age of 5.7 years (interquartile range 2.8-9.6) enrolled in HIV care. One-year cumulative incidence for death and LTF among pre-ART children was 4% (95% confidence interval [CI]: 3-5%) and 5% (95% CI: 4-6%), respectively. Overall, 2035 (63%) children initiated ART, median age 6.3 years (interquartile range 3.3-10.4): 1-year Kaplan-Meier estimates of death and LTF were 3% (95% CI: 3-4%) and 1% (95% CI: 1-2%), respectively. Factors associated with an increased hazard for death among pre-ART children included being <18 months old versus ≥5 years (adjusted sub hazard ratio [aSHR] = 4.4, 95% CI: 2.9-6.8) and World Health Organization stage IV versus I (aSHR = 4.1, 95% CI: 2.0-8.4), whereas children entering care through prevention of mother-to-child transmission had lower hazard than those from voluntary counseling and testing (aSHR = 0.50, 95% CI: 0.25-1.0). Markers of advanced disease, including severe immunosuppression (aSHR = 0.25, 95% CI: 0.12-0.54), and enrollment in care in rural versus urban clinics (aSHR = 0.71, 95% CI: 0.53-0.97) were protective against LTF. For children on ART, factors associated with hazard of death included younger age (adjusted hazard ratio [aHR] <18 months versus ≥5 years = 2.1, 95% CI: 1.3-3.6), severe malnutrition versus not malnourished (aHR = 3.2, 95% CI: 1.3-8.1), advanced World Health Organization stage (aHR IV versus I = 9.8, 95% CI: 3.5-27.4) and severe immunodeficiency versus no evidence (aHR = 2.3, 95% CI: 1.7-3.3). No associations were observed with LTF among children on ART.

CONCLUSIONS

The results demonstrate very high retention among children enrolled in HIV care in Rwanda. Younger children continue to be particularly vulnerable, underscoring the urgent need for early identification, rapid treatment initiation and long-term retention in care.

Factors associated with remaining on initial randomized efavirenz-containing regimens

OBJECTIVE

Efavirenz (EFV) along with two nucleoside reverse transcriptase inhibitors (NRTIs) is a recommended initial antiretroviral regimen. Understanding characteristics related to EFV success is clinically useful.

DESIGN

Data from 2220 antiretroviral-naive participants randomized to EFV and two to three NRTIs in four ACTG trials as well as a long-term cohort were analysed.

METHODS

Logistic regression, using inverse probability of censoring weighting to address selective-follow-up bias, was used to identify factors associated with EFV success (no treatment interruptions of >30 days, HIV RNA < 200 copies/ml) 1 year post initiation and at years 2-5 if successful at year 1.

RESULTS

Pretreatment characteristics were median age 38 years, 82% male, 40% white, 10% history of IDU (HxIDU), median CD4+ T-lymphocyte 227 cells/μl and 33% HIV RNA more than 100 ,000 copies/ml. In a multivariable model, factors associated with year 1 EFV success were race [white odds ratio (OR) 1.5; P < 0.001; Hispanic OR 1.5; P = 0.003 vs. black], no pretreatment sign/symptom grade 3 or higher (OR 1.7; P = 0.008) and no HxIDU (OR 1.7; P = 0.001). Predictors of EFV success at years 2-5 were no HxIDU (years 2-5; ORs 1.9-2.2); self-reported complete (4 days prior to study visit) adherence during year 1 (years 2-4; ORs 1.6-1.9); fewer missed visits during year 1 (years 2, 4, 5; ORs 0.92-0.98/1% increase); HIV RNA less than 50 copies/ml at year 1 (years 2, 3; ORs 1.9-2.2); and older age (>50 vs. ≤30 years) (years 2-4: ORs 2.3-3.7).

CONCLUSION

Characteristics predictive of EFV success in the short-term and longer term differed except for HxIDU. Behaviours occurring during year 1 were associated with EFV success over 5 years.

Implementation of mental health service has an impact on retention in HIV care: a nested case-control study in a japanese HIV care facility

Background

Poor retention in the care of patients with human immunodeficiency virus (HIV) is associated with adverse patient outcomes such as antiretroviral therapy failure and death. Therefore, appropriate case management is required for better patient retention; however, which intervention in case management is important has not been fully investigated. Meanwhile, in Japan, each local government is required to organize mental health services for patients with HIV so that a case manager at an HIV care facility can utilize them, but little is known about the association between implementation of the services and loss to follow-up. Therefore, we investigated that by a nested case-control study.

Methods

The target population consisted of all patients with HIV who visited Osaka National Hospital, the largest HIV care facility in western Japan, between 2000 and 2010. Loss to follow-up was defined as not returning for follow-up care more than 1 year after the last visit. Independent variables included patient demographics, characteristics of the disease and treatment, and whether the patients have received mental health services. For each case, three controls were randomly selected and matched.

Results

Of the 1620 eligible patients, 88 loss to follow-up cases were identified and 264 controls were matched. Multivariate-adjusted conditional logistic regression revealed that loss to follow-up was less frequent among patients who had received mental health services implemented by their case managers (adjusted odds ratio [95% confidence interval] 0.35 [0.16-0.76]). Loss to follow-up also occurred more frequently in patients who did not receive antiretroviral therapy (adjusted odds ratio [95% confidence interval], 7.51 [3.34-16.9]), who were under 30 years old (2.74 [1.36-5.50]), or who were without jobs (3.38 [1.58-7.23]).

Conclusion

Mental health service implementation by case managers has a significant impact on patient retention.

High loss to followup and early mortality create substantial reduction in patient retention at antiretroviral treatment program in north-west ethiopia

Background. There has been a rapid scale up of antiretroviral therapy (ART) in Ethiopia since 2005. We aimed to evaluate mortality, loss to followup, and retention in care at HIV Clinic, University of Gondar Hospital, north-west Ethiopia. Method. A retrospective patient chart record analysis was performed on adult AIDS patients enrolled in the treatment program starting from 1 March 2005. We performed survival analysis to determine, mortality, loss to followup and retention in care. Results. A total of 3012 AIDS patients were enrolled in the ART Program between March 2005 and August 2010. At the end of the 66 months of the program initiation, 61.4% of the patients were retained on treatment, 10.4% died, and 31.4% were lost to followup. Fifty-six percent of the deaths and 46% of those lost to followup occurred in the first year of treatment. Male gender (adjusted hazard ratio (AHR) was 3.26; 95% CI: 2.19–4.88); CD4 count ≤200 cells/μL (AHR 5.02; 95% CI: 2.03–12.39), tuberculosis (AHR 2.91; 95% CI: 2.11–4.02); bed-ridden functional status (AHR 12.88; 95% CI: 8.19–20.26) were predictors of mortality, whereas only CD4 count <200 cells/μL (HR = 1.33; 95% CI: (0.95, 1.88) and ambulatory functional status (HR = 1.65; 95% CI: (1.22, 2.23) were significantly associated with LTF. Conclusion. Loss to followup and mortality in the first year following enrollment remain a challenge for retention of patients in care. Strengthening patient monitoring can improve patient retention AIDS care.