Antiretroviral treatment interruption and loss to follow-up in two HIV cohorts in Australia and Asia: implications for 'test and treat' prevention strategy

Three-stage modeling of HIV infection and implications for antiretroviral therapy

We consider a deterministic model of HIV infection that involves macrophages as a long-term active reservoir to describe all three stages of the disease process: the acute stage, chronic infection, and the transition to AIDS. The proposed model is shown to retain crucial properties, such as the positivity of solutions, regardless of variations in model parameters. A dynamical analysis is performed to identify the local stability properties of the viral clearance steady state. This analysis illustrates how chronically infected macrophages can explain the progression to AIDS and provoke viral explosion, while previous models do not. We further demonstrate that the infected T-cell population, even if not responsible for the majority of new infections that lead to viral explosion, may contribute significantly to the transition amongst the three stages of infection. Moreover, we explore the implications of the model for the administration of antiretroviral therapy (ART) and provide quantitative estimates that emphasize the time sensitive nature of treatment initiation and the level of drug efficacy. Finally, we study the effects of treatment interruption on the disease dynamics predicted by the model and elucidate the influence of both interruption time and duration.

Antiretroviral treatment interruption and resumption within 16 weeks among HIV-positive adults in Jinan, China: a retrospective cohort study

Background

Treatment interruption has been found to increase the risk of opportunistic infections and death among HIV-positive adults, posing a challenge to fully realizing antiretroviral therapy (ART). However, it has been observed that short-term interruption (<16 weeks) was not associated with significant increases in adverse clinical events. There remains a dearth of evidence concerning the interruption and resumption of ART after short-term discontinuation in China.

Methods

HIV-positive adults who initiated ART in Jinan between 2004 and 2020 were included in this study. We defined ART interruption as more than 30 consecutive days off ART and used Cox regression to identify predictors of interruption. ART resumption was defined as a return to ART care within 16 weeks following discontinuation, and logistic regression was used to identify barriers.

Results

A total of 2,506 participants were eligible. Most of them were male [2,382 (95%)] and homosexual [2,109 (84%)], with a median age of 31 (IQR: 26-40) years old. Of all participants, 312 (12.5%) experienced a treatment interruption, and the incidence rate of interruption was 3.2 (95% CI: 2.8-3.6) per 100 person-years. A higher risk of discontinuation was observed among unemployed individuals [adjusted hazard ratio (aHR): 1.45, 95% CI: 1.14-1.85], with a lower education level (aHR: 1.39, 95% CI: 1.06-1.82), those with delayed ART initiation (aHR: 1.43, 95% CI: 1.10-1.85), receiving Alafenamide Fumarate Tablets at ART initiation (aHR: 5.19, 95% CI: 3.29-8.21). About half of the interrupters resumed ART within 16 weeks, and participants who delayed ART initiation, missed the last CD4 test before the interruption and received the "LPV/r+NRTIs" regimen before the interruption were more likely to discontinue treatment for the long term.

Conclusion

Antiretroviral treatment interruption remains relatively prevalent among HIV-positive adults in Jinan, China, and assessing socioeconomic status at treatment initiation will help address this issue. While almost half of the interrupters returned to care within 16 weeks, further focused measures are necessary to reduce long-term interruptions and maximize the resumption of care as soon as possible to avoid adverse clinical events.

Brief Report: Mortality After Loss to Follow-Up-A Linkage Study of People Living With HIV in Thailand and Malaysia

BACKGROUND

Linkage studies have reported high rates of previously unascertained mortality among people living with HIV (PLHIV) who have been lost to follow-up (LTFU). We assessed survival outcomes among PLHIV who were LTFU in Thailand and Malaysia, through linkages to a national death registry or HIV database.

METHODS

Data linkages with the national death registry or national HIV database were conducted in 2020 on all PLHIV who met LTFU criteria while enrolled in care at participating HIV clinical sites. LTFU was defined as having no documented clinical contact in the previous year, excluding transfers and deaths. Survival time was analyzed using the Cox regression, stratified by site.

RESULTS

Data linkages were performed for 489 PLHIV who had been LTFU at sites in Malaysia (n = 2) and Thailand (n = 4). There were 151 (31%) deaths after being LTFU; the mortality rate was 4.89 per 100 person-years. Risk factors for mortality after being LTFU were older age [41-50 years: hazard ratio (HR) = 1.99, 95% confidence interval (CI): 1.08 to 3.68; and older than 50 years: HR = 4.93, 95% CI: 2.63 to 9.22; vs. age 30 years or younger]; receiving NRTI + PI (HR = 1.87, 95% CI: 1.22 to 2.85 vs. NRTI + NNRTI); positive hepatitis C antibody (HR = 2.25, 95% CI: 1.40 to 3.62); and having previous AIDS illness (HR = 1.45, 95% CI: 1.03 to 2.05). An improved survival was seen with a higher CD4 count (CD4 351-500 cells/µL: HR = 0.40, 95%CI: 0.21-0.76; and CD4 >500 cells/µL: HR = 0.43, 95%CI: 0.25-0.75; vs. CD4 ≤200 cells/µL).

CONCLUSIONS

Almost one-third of PLHIV who were LTFU in this cohort had died while out of care, emphasizing the importance of efforts to reengage PLHIV after they have been LTFU and ensure they have access to ongoing ART.

Factors Affecting Virological Outcome When First-Line Antiretroviral Therapy Is Reintroduced After Unplanned Interruption

There is no guideline concerning choice of antiretroviral therapy (ART) for HIV-infected patients after unplanned interruption. We conducted a retrospective cohort study of HIV-infected patients reintroduced to first-line ART after having unplanned interruption for at least 1 month. Viral load was evaluated at 6 to 18 months after the reintroduction. There were 100 patients included in our study, and 55 of them achieved virological success. History of single interruption (adjusted odds ratio [aOR] 5.51%, 95% confidence interval [CI] 1.82-16.68, P = .003) and CD4 count ≥200 cell/mm³ at the time of reintroduction (aOR 4.33, 95% CI 1.14-16.39, P = .031) increased likelihood to achieve virological success.

HIV patients retention and attrition in care and their determinants in Ethiopia: a systematic review and meta-analysis

BACKGROUND

There is paucity of evidence on the magnitude of HIV patients' retention and attrition in Ethiopia. Hence, the aim of this study was to determine the pooled magnitude of HIV patient clinical retention and attrition and to identify factors associated with retention and attrition in Ethiopia.

METHODS

Systematic review and meta-analysis were done among studies conducted in Ethiopia using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline. Both published and unpublished studies conducted from January 1, 2005 to June 6th, 2019 were included. Major databases and search engines such as Google Scholar, PUBMED, African Journals Online (AJOL) and unpublished sources were searched to retrieve relevant articles. Data were assessed for quality, heterogeneity and publication bias. Analysis was conducted using STATA version 14 software.

RESULT

From a total of 45 studies 546,250 study participants were included in this review. The pooled magnitude of retention in care among HIV patients was 70.65% (95% CI, 68.19, 73.11). The overall magnitude of loss to follow up 15.17% (95% CI, 11.86, 18.47), transfer out 11.17% (95% CI, 7.12, 15.21) and death rate were 6.75% (95% CI, 6.22, 7.27). Major determinants of attrition were being unmarried patient (OR 1.52, 95% CI: 1.15-2.01), non-disclosed HIV status (OR 6.36, 95% CI: 3.58-11.29), poor drug adherence (OR 6.60, 95% CI: 1.41-30.97), poor functional status (OR 2.11, 95% CI: 1.33-3.34), being underweight (OR 2.21, 95% CI: 1.45-3.39) and advanced clinical stage (OR 1.85, 95% CI: 1.36-2.51). Whereas absence of opportunistic infections (OR 0.52, 95% CI: 0.30-0.9), normal hemoglobin status (OR 0.29, 95% CI: 0.20-0.42) and non-substance use (OR 95% CI: 0.41, 0.17-0.98) were facilitators of HIV patient retention in clinical care.

CONCLUSION

The level of retention to the care among HIV patients was low in Ethiopia. Socio-economic, clinical, nutritional and behavioral, intervention is necessary to achieve adequate patient retention in clinical care.

Predictors of lost to follow-up in a "test and treat" programme among adult women with high-risk sexual behavior in Kampala, Uganda

BACKGROUND

Immediate uptake of antiretroviral therapy (ART) after an HIV-positive diagnosis (Test and Treat) is now being implemented in Uganda. Data are limited on lost to follow-up (LTFU) in high-risk cohorts that have initiated 'Test and Treat'. We describe LTFU in a cohort of women of high-risk sexual behaviour who initiated ART under "Test and Treat".

METHODS

We performed a retrospective cohort study of participant records at the Good Health for Women Project (GHWP) clinic, a clinic in Kampala for women at high-risk of HIV-infection. We included HIV positive women ≥18 years who initiated ART at GHWP between August 2014 and March 2018. We defined LTFU as not taking an ART refill for ≥3 months from the last clinic appointment among those not registered as dead or transferred to another clinic. We used the Kaplan-Meier technique to estimate time to LTFU after ART initiation. Predictors of LTFU were assessed using a multivariable Cox proportional hazards model.

RESULTS

The mean (±SD) age of the 293 study participants was 30.3 (± 6.5) years, with 274 (94%) reporting paid sex while 38 (13%) had never tested for HIV before enrolment into GHWP. LTFU within the first year of ART initiation was 16% and the incidence of LTFU was estimated at 12.7 per 100 person-years (95%CI 9.90-16.3). In multivariable analysis, participants who reported sex work as their main job at ART initiation (Adjusted Hazards Ratio [aHR] =1.95, 95%CI 1.10-3.45), having baseline WHO clinical stage III or IV (aHR = 2.75, 95% CI 1.30-5.79) were more likely to be LTFU.

CONCLUSION

LTFU in this cohort is high. Follow up strategies are required to support women on Test and Treat to remain on treatment, especially those who engage in sex work and those who initiate ART at a later stage of disease.

Adherence to Antiretroviral Regimens in Australia: A Nationwide Cohort Study

The lifetime use of combination antiretroviral therapy (cART) highlights the need to understand patterns of and factors associated with adherence to cART. In this cohort study using a 10% random sample of dispensing claims data for eligible Australians, we identified 2042 people dispensed cART between January 2016 and December 2017 (mean age 48.0 ± 12.0 years old, 88.6% male, and 85.9% treatment experienced). We considered people to be adherent if the proportion of treatment coverage days was ≥80% in the 360 days after their first observed cART dispensing. We also used group-based trajectory modeling (GBTM) to examine different patterns of adherence for 360 days from first observed cART dispensing. Most commonly, people receiving cART were treated with two nucleoside/nucleotide reverse transcriptase inhibitors with an integrase strand transfer inhibitors (INSTI-46.6%). Overall, 1708 people [83.6% (95% confidential interval 82.0-85.3%)] remained adherent over 360 days. GBTM identified three distinct adherence patterns: nearly always adherent [67.8% (63.7-71.9%) of the cohort], moderate adherence [26.6% (23.0-30.1%)], and low adherence [5.6% (4.1-7.2%)]. People were more likely to belong to the "nearly always adherent" trajectory if they were older (per additional year of age), treated with an INSTI regimen, and on treatment for more than 6 months. Our study demonstrates that the 360-day adherence to cART is generally high, but approximately one-third maintain a moderate or low adherence pattern. The use of INSTI regimens and additional support of treatment adherence, especially among younger people and those initiating therapy, may further improve adherence.

Are there differences in HIV retention in care between female and male patients in Indonesia? A multi-state analysis of a retrospective cohort study

BACKGROUND

Little is known about HIV treatment outcomes in Indonesia, which has one of the most rapidly growing HIV epidemics worldwide.

METHODS

We examined possible differences in loss to follow-up (LTFU) and survival between HIV-infected females and males over a 7-year period in an HIV clinic in Bandung, West Java. Data imputation was performed on missing covariates and a multi-state Cox regression was used to investigate the effects of sex and other covariates on patient transitions among four states: (1) clinic enrollment with HIV, (2) initiation/continuation/re-initiation of antiretroviral therapy (ART), (3) LTFU, and (4) death.

RESULTS

We followed 3215 patients (33% females), for a total of 8430 person-years. ART was used by 59% of patients at some point. One-year retention was 73% for females and 77% for males (p = 0.06). One-year survival was 98% for both females and males (p = 0.15). Females experienced a higher relative hazard to transition from HIV to LTFU (adjusted hazard ratio 1.21; 95% confidence interval 1.00-1.45), but this decreased after adjustments for clinical variables (aHR 0.94; 95% CI 0.79-1.11). Similarly, a lower relative hazard in females to transition from ART to death (aHR 0.59; 95% CI 0.35-0.99) decreased after adjustments for demographic variables.

CONCLUSION

This Indonesian cohort has low ART uptake and poor overall pre- and post-ART retention. Female-male differences in survival and retention were gone after adjusting for clinical and sociodemographic factors such as CD4 count and education level. Efforts should be made to improve retention among patients with lower education.

Harnessing nanostructured systems for improved treatment and prevention of HIV disease

Combination antiretroviral therapy effectively controls human immunodeficiency virus (HIV) viral replication, delaying the progression to acquired immune deficiency syndrome and improving and extending quality of life of patients. However, the inability of antiretroviral therapeutics to target latent virus and their poor penetration of viral reserve tissues result in the need for continued treatment for the life of the patient. Side effects from long-term antiretroviral use and the development of drug resistance due to patient noncompliance are also continuing problems. Nanostructured systems of antiretroviral therapeutics have the potential to improve targeted delivery to viral reservoirs, reduce drug toxicity, and increase dosing intervals, thereby improving treatment outcomes and enhancing patient adherence. Despite these advantages, very few nanostructured antiretroviral delivery systems have made it to clinical trials due to challenges in preclinical and clinical development. In this context, we review the current challenges in HIV disease management, and the recent progress in leveraging the unique performance of nanostructured systems in therapeutic delivery for improved treatment and prevention of this incurable human disease.

Antiretroviral therapy interruptions: impact on HIV treatment and transmission

Introduction

Successful management of pediatric and adult human immunodeficiency virus (HIV) disease includes lifelong administration of antiretroviral therapy (ART). The need for the continuous use of antiretroviral drugs throughout the life course poses a challenge to children, adolescents, and adults living with HIV and their caregivers. Historically, treatment interruptions have been viewed as a negative therapeutic strategy. Recently, however, treatment interruptions or treatment reduction strategies have become a focus of investigations as innovative approaches to the long-term management of HIV disease. Current challenges with treatment interruptions include identifying an appropriate timeframe for length of interruptions and identifying HIV patient populations in whom the treatment interruption can be successful.

Objective

In this review, we aimed at summarizing recent studies of planned and unplanned treatment interruptions in children and adults living with HIV.

Materials and methods

We searched two databases (PubMed and Cochrane Controlled Trials Register) using keywords (HIV OR AIDS OR acquired immunodeficiency syndrome OR HIV-1 OR antiretroviral) AND (treatment interruption OR planned interruption OR therapeutic interruption OR unplanned interruption), for published randomized and nonrandomized clinical trials and observational cohort studies in children and adults (from birth to 99 years of age) in global settings covering a period from 2012 to 2018. In this review, only the studies that contained pediatric and adolescent populations with baseline immunological, virological, and clinical characteristics and outcomes after treatment interruption were included.

Results

A total of 174 eligible citations from the two databases were identified. We identified 10 prospective treatment interruption studies on children (five studies) and adults (five studies) during 2012–2018 with a total of 863 pediatric and 273 adult subjects. Collectively, recent studies on children and adults with HIV infection suggest that treatment interruptions with proper monitoring can be successful by instituting well-defined immunological and virological parameters or thresholds such as CD4 count, CD4%, and HIV RNA viral load that identify low-risk populations with treatment failure. In addition to standard virological and immunological outcome measurements, selected biomarkers that help detect early immune activation may also be useful in the monitoring of treatment interruption.

Conclusion

Treatment interruptions in adult and especially pediatric patients with well-controlled HIV disease may provide an alternative opportunity to optimize long-term HIV management by minimizing drug-associated toxicity and improving long-term adherence and quality of life.

The Effect of Monitoring Viral Load and Tracing Patients Lost to Follow-up on the Course of the HIV Epidemic in Malawi: A Mathematical Model

Background

Antiretroviral therapy (ART) reduces HIV transmission, but treated patients may again become infectious. We used a mathematical model to determine whether ART as prevention is more effective if viral load (VL) is routinely monitored and patients lost to follow-up (LTFU) traced.

Methods

We simulated ART cohorts to parameterize a deterministic transmission model calibrated to Malawi. We investigated the following strategies for improving treatment and retention: monitoring VL every 12 or 24 months, tracing patients LTFU, or a generic strategy leading to uninterrupted treatment. We tested 3 scenarios, where ART scale-up continues at current (Universal ART), reduced (Failed scale-up), or accelerated speed (Test&Treat).

Results

In the Universal ART scenario, between 2017 and 2020 (2050), monitoring VL every 24 months prevented 0.5% (0.9%), monitoring every 12 months prevented 0.8% (1.4%), tracing prevented 0.3% (0.5%), and uninterrupted treatment prevented 5.5% (9.9%) of HIV infections. Failed scale-up resulted in 25% more infections than the Universal ART scenarios, whereas Test&Treat resulted in 7%–8% less.

Conclusions

Test&Treat reduces transmission of HIV, despite individual cases of treatment failure and ART interruption. Whereas viral load monitoring and tracing have only a minor impact on transmission, interventions that aim to minimize treatment interruptions can further increase the preventive effect of ART.

Intermittent treatment of severe influenza

Severe, long-lasting influenza infections are often caused by new strains of the virus. The long duration of these infections leads to an increased opportunity for the emergence of drug resistant mutants. This is particularly problematic since for new strains there is often no vaccine, so drug treatment is the first line of defense. One strategy for trying to minimize drug resistance is to apply drugs periodically. During treatment phases the wild-type virus decreases, but resistant virus might increase; when there is no treatment, wild-type virus will hopefully out-compete the resistant virus, driving down the number of resistant virus. A stochastic model of severe influenza is combined with a model of drug resistance to simulate long-lasting infections and intermittent treatment with two types of antivirals: neuraminidase inhibitors, which block release of virions; and adamantanes, which block replication of virions. Each drug's ability to reduce emergence of drug resistant mutants is investigated. We find that cell regeneration is required for successful implementation of intermittent treatment and that the optimal cycling parameters change with regeneration rate.

Beliefs in Antiretroviral Treatment and Self-Efficacy in HIV Management are Associated with Distinctive HIV Treatment Trajectories

An online survey was conducted among people living with HIV (PLHIV) in Australia to discern key factors associated with distinctive ART use patterns. The sample (N = 358), was further divided into three groups: those on ART continuously since initiation (n = 208, 58.1%); those on ART intermittently (n = 117, 32.7%); and those not on ART at the time of survey (n = 33, 9.2%). ART non-users were the most likely to hold serious concerns about ART that outweighed perceived necessities (benefits) from ART (AOR = 0.13; 95% CI 0.06-0.29; p < 0.001). They were also the least self-efficacious in HIV disease management (AOR = 0.29; 95% CI 0.09-0.87; p = 0.028). Intermittent ART users were more likely to receive their HIV diagnosis prior to 2003 (AOR = 0.38; 95% CI 0.28-0.53; p < 0.001) and perceive lower HIV management self-efficacy (AOR = 0.50, 95% CI 0.28-0.87; p = 0.015) than continuous users. ART-related beliefs and perceived self-efficacy in HIV self-management play an important role in achieving universal treatment uptake and sustained high levels of adherence.

Ten year experience with antiretroviral treatment in Cambodia: Trends in patient characteristics and treatment outcomes

BACKGROUND

Although HIV disease stage at ART initiation critically determines ART outcomes, few reports have longitudinally monitored this within Asia. Using prospectively collected data from a large ART program at Sihanouk Hospital Center of Hope in Cambodia, we report on the change in patient characteristics and outcomes over a ten-year period.

METHODS

We conducted a retrospective analysis including all adults (≥ 18 years old) starting ART from March 2003-March 2013 in a non-governmental hospital in Phnom Penh, Cambodia. The cumulative incidence of death, lost to follow-up (LTFU), attrition (death or LTFU) and first line treatment failure were calculated using Kaplan-Meier methods. Independent risk factors for these outcomes were determined using Cox regression modeling.

RESULTS

Over the ten-year period, 3581 patients initiated ART with a median follow-up time of 4.8 years (IQR 2.8-7.2). The median age was 35 years (IQR 30-41), 54% were female. The median CD4 count at ART initiation increased from 22 cells/μL (IQR 4-129) in 2003 to 218 (IQR 57-302) in 2013. Over the 10 year period, a total of 282 (7.9%) individuals died and 433 (12.1%) were defined LTFU. Program attrition (died or LTFU) was 11.1% (95% CI: 10.1%- 12.4%) at one year, 16.3% (95% CI: 15.1%-17.6%) at three years, 19.8% (95% CI: 18.5%-21.2%) at five years and 23.3% (95% CI: 21.6-25.1) at ten years. Male sex and low baseline body mass index (BMI) were associated with increased attrition. Factors independently associated with mortality included a low baseline CD4 count, older age, male sex, low baseline BMI and hepatitis B co-infection. Individuals aged above 40 years old had an increased risk of mortality but were less likely to LTFU. There were a total of 137 individuals with first line ART failure starting second line treatment. The probability of first line failure was estimated at 2.8% (95% CI: 2.3%-3.4%) at 3 years, 4.6% (95% CI: 3.9%-5.5%) at 5 years and 7.8% (95% CI 4.8%-12.5%) at ten years of ART. The probability was particularly high in the first few program years. A lower risk was observed among individuals starting ART during the 2006-2008 period. Factors independently associated with an increased risk of treatment failure included ART-experience, NVP-based ART and a baseline CD4 count below 200 cells/μL.

CONCLUSIONS

Overall program outcomes were fair, and generally compare well to other reports from the region. Despite gradually earlier initiation of ART over the ten year period, ART is still initiated at too low CD4 count levels, warranting increased efforts for early HIV diagnosis and enrolment/retention into HIV care. Tailored strategies for poor prognostic groups (older age, male, low BMI) should be designed and evaluated.

Motivations and Barriers to Treatment Uptake and Adherence Among People Living with HIV in Australia: A Mixed-Methods Systematic Review

In Australia, approximately 30% of people diagnosed with HIV are not accessing treatment and 8% of those receiving treatment fail to achieve viral suppression. Barriers limiting effective care warrant further examination. This mixed-methods systematic review accessed health and social sector research databases between November and December 2015 to identify studies that explored the perspective of people living with HIV in Australia. Articles were included for analysis if they described the experiences, knowledge, attitudes and beliefs, in relation to treatment uptake and adherence, published between January 2000 and December 2015. Quality appraisal utilised the Mixed Methods Appraisal Tool Version 2011. Seventy-two studies that met the inclusion criteria were reviewed. The interplay of lack of knowledge, fear, stigma, physical, emotional and social issues were found to negatively impact treatment uptake and adherence. Strategies targeting both the individual and the wider community are needed to address these barriers.

A Decade of Combination Antiretroviral Treatment in Asia: The TREAT Asia HIV Observational Database Cohort

Asian countries have seen the expansion of combination antiretroviral therapy (cART) over the past decade. The TREAT Asia HIV Observational Database (TAHOD) was established in 2003 comprising 23 urban referral sites in 13 countries across the region. We examined trends in treatment outcomes in patients who initiated cART between 2003 and 2013. Time of cART initiation was grouped into three periods: 2003-2005, 2006-2009, and 2010-2013. We analyzed trends in undetectable viral load (VL; defined as VL <400 copies/ml), CD4 changes from pre-cART levels, and overall survival. Of 6,521 patients included, the overall median CD4 count at cART initiation was 120 cells/μl (interquartile range: 38-218). Despite an increase over time, pre-cART CD4 counts remained <200 cells/μl. Adjusted analyses showed undetectable VL was more likely when starting cART in later years [2006-2009: odds ratio (OR) = 1.76, 95% confidence interval (CI) (1.45, 2.15); and 2010-2013: OR = 3.04, 95% CI (2.33, 3.97), all p < .001, compared to 2003-2005], and survival was improved [2006-2009: subdistribution hazard ratio (SHR) = 0.41, 95% CI (0.27, 0.61), 2010-2013: SHR = 0.29, 95% CI (0.17, 0.49), all p < .001, compared to 2003-2005]. No differences in CD4 response was observed over time. Age and CD4 levels prior to cART initiation were associated with all three treatment outcomes, with older age and higher CD4 counts being associated with undetectable VL. Survival and VL response on cART have improved over the past decade in TAHOD, although CD4 count at cART initiation remained low. Greater effort should be made to facilitate earlier HIV diagnosis and linkage to care and treatment, to achieve greater improvements in treatment outcomes.

Effects of unplanned treatment interruptions on HIV treatment failure - results from TAHOD

OBJECTIVES

Treatment interruptions (TIs) of combination antiretroviral therapy (cART) are known to lead to unfavourable treatment outcomes but do still occur in resource-limited settings. We investigated the effects of TI associated with adverse events (AEs) and non-AE-related reasons, including their durations, on treatment failure after cART resumption in HIV-infected individuals in Asia.

METHODS

Patients initiating cART between 2006 and 2013 were included. TI was defined as stopping cART for >1 day. Treatment failure was defined as confirmed virological, immunological or clinical failure. Time to treatment failure during cART was analysed using Cox regression, not including periods off treatment. Covariables with P < 0.10 in univariable analyses were included in multivariable analyses, where P < 0.05 was considered statistically significant.

RESULTS

Of 4549 patients from 13 countries in Asia, 3176 (69.8%) were male and the median age was 34 years. A total of 111 (2.4%) had TIs due to AEs and 135 (3.0%) had TIs for other reasons. Median interruption times were 22 days for AE and 148 days for non-AE TIs. In multivariable analyses, interruptions >30 days were associated with failure (31-180 days HR = 2.66, 95%CI (1.70-4.16); 181-365 days HR = 6.22, 95%CI (3.26-11.86); and >365 days HR = 9.10, 95% CI (4.27-19.38), all P < 0.001, compared to 0-14 days). Reasons for previous TI were not statistically significant (P = 0.158).

CONCLUSIONS

Duration of interruptions of more than 30 days was the key factor associated with large increases in subsequent risk of treatment failure. If TI is unavoidable, its duration should be minimised to reduce the risk of failure after treatment resumption.

Temporal trends of time to antiretroviral treatment initiation, interruption and modification: examination of patients diagnosed with advanced HIV in Australia

Introduction

HIV prevention strategies are moving towards reducing plasma HIV RNA viral load in all HIV-positive persons, including those undiagnosed, treatment naïve, on or off antiretroviral therapy. A proxy population for those undiagnosed are patients that present late to care with advanced HIV. The objectives of this analysis are to examine factors associated with patients presenting with advanced HIV, and establish rates of treatment interruption and modification after initiating ART.

Methods

We deterministically linked records from the Australian HIV Observational Database to the Australian National HIV Registry to obtain information related to HIV diagnosis. Logistic regression was used to identify factors associated with advanced HIV diagnosis. We used survival methods to evaluate rates of ART initiation by diagnosis CD4 count strata and by calendar year of HIV diagnosis. Cox models were used to determine hazard of first ART treatment interruption (duration >30 days) and time to first major ART modification.

Results

Factors associated (p<0.05) with increased odds of advanced HIV diagnosis were sex, older age, heterosexual mode of HIV exposure, born overseas and rural–regional care setting. Earlier initiation of ART occurred at higher rates in later periods (2007–2012) in all diagnosis CD4 count groups. We found an 83% (69, 91%) reduction in the hazard of first treatment interruption comparing 2007–2012 versus 1996–2001 (p<0.001), and no difference in ART modification for patients diagnosed with advanced HIV.

Conclusions

Recent HIV diagnoses are initiating therapy earlier in all diagnosis CD4 cell count groups, potentially lowering community viral load compared to earlier time periods. We found a marked reduction in the hazard of first treatment interruption, and found no difference in rates of major modification to ART by HIV presentation status in recent periods.

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.

Cost-effectiveness of antiretroviral therapy expansion strategies in Vietnam

This study determines an optimal strategy for scaling up ART in Vietnam by examining three initiation thresholds [350 cells/mm(3), 500 cells/mm(3), and treat all people living with HIV (PLHIV) regardless of CD4 cell counts] and treatment commencement rates among treatment-eligible PLHIV ranging from 5% to 100% within 12 months of diagnosis. Incremental cost-effectiveness ratios (ICERs) were calculated using a Markov model, based on data from a cohort of 3449 patients who initiated ART between January 1, 2005 and December 31, 2009 in 13 outpatient clinics across six provinces in Vietnam. Our analyses indicated that raising treatment eligibility criteria, in line with WHO guidelines (CD4 ≤500 cells/mm(3)) or removing CD4-based criteria would both be cost-effective in Vietnam. However, the cost-effective strategy from an economic viewpoint is first to increase coverage substantially among those with lowest CD4 levels, and only when coverage increases towards saturation should initiation criteria be lifted. Universal coverage under current guidelines would cost an additional $85 million and $96 million per year if the treatment threshold was 500 cells/mm(3). These scenarios would avert 15,000 and 22,000 HIV-related deaths in 2010-2019, with ICERs of $500-$660 per QALY gained. It is imperative to increase treatment coverage for newly diagnosed PLHIV in Vietnam according to the current guidelines prior to increasing the CD4 threshold for ART initiation.