Antiretroviral Refill Adherence Correlates with, But Poorly Predicts Retention in HIV Care

Modeling Adherence Interventions Among Youth with HIV in the United States: Clinical and Economic Projections

The Adolescent Medicine Trials Network for HIV/AIDS Interventions is evaluating treatment adherence interventions (AI) to improve virologic suppression (VS) among youth with HIV (YWH). Using a microsimulation model, we compared two strategies: standard-of-care (SOC) and a hypothetical 12-month AI that increased cohort-level VS in YWH in care by an absolute ten percentage points and cost $100/month/person. Projected outcomes included primary HIV transmissions, deaths and life-expectancy, lifetime HIV-related costs, and incremental cost-effectiveness ratios (ICERs, $/quality-adjusted life-year [QALY]). Compared to SOC, AI would reduce HIV transmissions by 15% and deaths by 12% at 12 months. AI would improve discounted life expectancy/person by 8 months at an added lifetime cost/person of $5,300, resulting in an ICER of $7,900/QALY. AI would be cost-effective at $2,000/month/person or with efficacies as low as a 1 percentage point increase in VS. YWH-targeted adherence interventions with even modest efficacy could improve life expectancy, prevent onward HIV transmissions, and be cost-effective.

Correlation of pre-exposure prophylaxis adherence to a mental health diagnosis or experience of childhood trauma in high-risk youth

Pre-exposure prophylaxis (PrEP) with tenofovir disoproxil fumarate (TDF)/emtricitabine is 99% effective in preventing HIV when taken daily. Young men/transgender women of color who have sex with men are the most at risk to become infected with HIV, with the lowest PrEP adherence. We investigated the association of depression, anxiety, and history of childhood trauma with PrEP adherence. PrEP adherence was measured by urine TDF testing. Patients were evaluated for depression (Patient Health Questionnaire-9 [PHQ-9]), anxiety (Generalized Anxiety Disorder-7 [GAD-7]), and history of childhood trauma (Adverse Childhood Experiences [ACEs]). Urine TDF levels were compared across scores on each screening tool using a Student’s t-test. A p-value of ≤ 0.05 was considered significant. Thirty-one subjects (mean age: 21.7 years, SD: 2.8) were enrolled between 3/2015 and 7/2016. Lower PrEP adherence was associated with a GAD-7 score diagnostic for generalized anxiety (80.7% versus 92.7%, p = 0.04) and a high ACE score (4+) (84.5% versus 95.7%, p = 0.05). A PHQ-9 score diagnostic for major depression was not associated with PrEP adherence. The presence of generalized anxiety and a history of childhood trauma, but not major depression, were associated with decreased PrEP adherence. The benefits of mental health interventions and trauma-informed care in PrEP programs should be considered in larger studies to potentially increase adherence.

Recommended method for health services to determine adherence to antiretroviral therapy: a comparison of three models

The medication possession ratio (MPR) method is commonly used for the determination of antiretroviral medication adherence. However, different ways of calculating MPR and methodological issues hinder the interpretation of the results and the reproducibility of the method. Thus, this study used three different models of MPR calculation and aimed to identify the one that best represents the situation of patient adherence. The results show that there was a statistically significant difference between the adherence rates determined by the three models, which indicates the need to specify the parameters used for calculation in the MPR method. However, the models individually were found to be related to viral suppression, but none of them had a greater effect than the other in this regard. The model that used residual medication (RM) and a fixed period of analysis allowed for a more precise identification of the number of doses that the patient used when compared to the others. Health services should avoid the application of the model using a variable analysis period. This study found that RM and the period of analysis considered are the main influencing factors in the accuracy of adherence results when the MPR method is used.

Brief Report: The Association of Chronic Pain and Long-Term Opioid Therapy With HIV Treatment Outcomes

BACKGROUND

Chronic pain occurs in up to 85% of persons living with HIV and is commonly treated with long-term opioid therapy (LTOT). We investigated the impact of chronic pain and LTOT on HIV outcomes.

METHODS

This was prospective cohort study conducted between July 2015 and July 2016 in 5 HIV primary care clinics. Chronic pain was defined as ≥moderate pain for ≥3 months on the Brief Chronic Pain Questionnaire. Chronic pain and LTOT were assessed at an index visit. Suboptimal retention, defined as at least one "no-show" to primary care, and virologic failure were measured over the subsequent year. Multivariable logistic regression models were built for each outcome adjusting for site.

RESULTS

Among 2334 participants, 25% had chronic pain, 27% had suboptimal retention, 12% had virologic failure, and 19% were prescribed LTOT. Among individuals not on LTOT, chronic pain was associated with increased odds of suboptimal retention [adjusted odds ratio (aOR) 1.46, 95% confidence interval (CI): 1.10 to 1.93, P = 0.009] and virologic failure (aOR 1.97, 95% CI: 1.39 to 2.80, P < 0.001). Among individuals with chronic pain, there was no association between LTOT and retention, but LTOT was associated with lower rates of virologic failure (aOR 0.56, 95% CI: 0.33 to 0.96, P = 0.03).

CONCLUSIONS

Chronic pain in participants not on LTOT was associated with virologic failure. This reinforces the need to identify effective chronic pain treatments for persons living with HIV and investigate their impact on HIV outcomes. The apparent protective association between LTOT and virologic failure in those with pain merits further exploration.

Delivery of TDF/FTC for Pre-exposure Prophylaxis to Prevent HIV-1 Acquisition in Young Adult Men Who Have Sex With Men and Transgender Women of Color Using a Urine Adherence Assay

BACKGROUND

Pre-exposure prophylaxis (PrEP) for HIV prevention with daily tenofovir and emtricitabine is effective when taken consistently. Currently, there is no objective way to monitor PrEP adherence. Urine has been shown to be highly correlated with plasma tenofovir levels, with urine tenofovir levels >1000 ng/mL demonstrating recent (1-2 days) adherence to PrEP.

SETTING

This study was conducted at an urban community health center in Philadelphia, Pennsylvania.

METHODS

PrEP was administered to 50 young men who have sex with men and transgender women of color using weekly, biweekly, and/or monthly dispensation schedules. Primary objectives were retention at 48 weeks (in care at week 48 and completing ≥50% of medication pickups) and adherence assessed by urine tenofovir levels. Risk behaviors and sexually transmitted infection diagnoses were also collected.

RESULTS

Seventy percent of participants were retained in care at 48 weeks. The proportion of subjects with urine tenofovir consistent with recent adherence was 80, 74.4, 82.4, 82.4, and 69.7% at weeks 4, 12, 24, 36, and 48, respectively. Sixty-one sexually transmitted infections were diagnosed over 231 screenings throughout 48 weeks, with no significant change between the first and second 24-week periods (P = 0.43; 0 seroconversions). At week 48, more than half of subjects reported an increase or no change in condom use, an increase in their ability to discuss HIV with partners, and no change in number of sexual partners from baseline.

CONCLUSIONS

These data demonstrate PrEP can be successfully delivered to a high-risk population with high program retention and medication adherence measured by urine tenofovir levels.

Brief Report: Short-Term Adherence Marker to PrEP Predicts Future Nonretention in a Large PrEP Demo Project: Implications for Point-of-Care Adherence Testing

BACKGROUND

Objective adherence metrics for tenofovir (TFV) disoproxil fumarate/emtricitabine (FTC)-based pre-exposure prophylaxis (PrEP) were critical for interpretation of efficacy in PrEP clinical trials, and there is increasing interest in using drug levels to tailor interventions for reengagement and adherence. Point-of-care immunoassays for TFV, which examine short-term adherence, are in development. However, the ability of poor short-term and long-term adherence to predict future PrEP nonretention is unknown.

SETTING

Secondary data analysis of a large, prospective multi-site U.S. PrEP demonstration project.

METHODS

An adjusted Cox-proportional hazards model examined the relationship of dried blood spot (DBS) levels of FTC-triphosphate (FTC-TP) or TFV-diphosphate (TFV-DP), measures of short-term and long-term PrEP adherence, respectively, with future study nonretention.

RESULTS

Overall, 294 individuals (median age 33 years) contributed drug levels within the U.S. PrEP demonstration project. By the end of study, 27% were lost to follow-up, 25% had at least one undetectable FTC-TP level indicating poor short-term adherence, and 29% had a drug level indicating suboptimal long-term adherence (TFV-DP <700 fmol/punch). The strongest factor associated with future study nonretention using a binary drug-level cut-off was an undetectable DBS FTC-TP level (adjusted hazard ratio 6.3; 95% confidence interval 3.8 to 10.2). The suboptimal long-term adherence based on low DBS TFV-DP levels was also associated with nonretention (adjusted hazard ratio 4.3; 95% confidence interval: 2.4 to 7.6).

CONCLUSIONS

Both short- and long-term metrics of PrEP adherence are strongly associated with future loss to follow-up in a U.S. demonstration project study. Short-term metrics of adherence, once available at the point-of-care, could be used to direct real-time tailored retention and adherence interventions.

Impact of insurance coverage on HIV transmission potential among antiretroviral therapy-treated youth living with HIV

OBJECTIVE

To identify the prevalence of high HIV transmission potential in a cohort of youth living with HIV (YLWH), and determine the impact of insurance coverage on potential for HIV transmission.

DESIGN

Retrospective cohort study of antiretroviral therapy (ART)-treated YLWH at a US adolescent HIV clinic, 2002-2015.

METHODS

The primary exposure was presence or absence of insurance, defined as private, public or pharmacy-only coverage. The primary outcome was high HIV transmission potential, defined as time-concurrent incident bacterial sexually transmitted infections (STI) (gonorrhea, chlamydia or syphilis) and HIV RNA greater than 1500 copies/ml. Marginal structural models adjusting for baseline demographic covariates, prior history of STI and time-varying retention in care assessed the relationship between insurance status and HIV transmission potential.

RESULTS

Participants (n = 240) were followed for a median of 22 (IQR 8.1-49) months after ART initiation, and were predominately African-American men and transgender women who have sex with men, with a median age at HIV diagnosis of 19 years (IQR 17-21). We identified 37 (15%) participants with at least one episode of high HIV transmission potential. Insurance coverage was associated with a greater than 50% lower odds of high HIV transmission potential (aOR 0.46, 95% CI 0.26-0.84), and history of STI at or before entry to HIV care conferred more than three-fold higher odds of high transmission potential (aOR 3.21, 95% CI 1.55-6.63).

CONCLUSION

We found 15% of YLWH to have episodic high HIV transmission potential despite receiving ART. Insurance coverage, including pharmacy-only benefits, was protective against transmission risk, suggesting a pivotal role for universal ART coverage in treatment as prevention.

Brief Report: CYP2B6 516G>T Minor Allele Protective of Late Virologic Failure in Efavirenz-Treated HIV-Infected Patients in Botswana

BACKGROUND

CYP2B6 polymorphisms that affect efavirenz (EFV) concentrations are common, but the effect of this polymorphism on HIV virologic failure in clinical practice settings has not fully been elucidated. Our objective was to investigate the relationship between the CYP2B6 516G>T genotype and late virologic failure in patients treated with EFV in Gaborone, Botswana.

SETTING

We performed a case-control study that included 1338 HIV-infected black Batswana on EFV-based antiretroviral therapy (ART). Patients were approached for enrollment during regular visits at one of the outpatient HIV clinics between July 2013 and April 2014.

METHODS

Cases experienced late HIV failure, defined as plasma HIV RNA >1000 copies/mL after maintaining viral suppression (<400 copies/mL) for at least 6 months. For each case, a total of 4 control patients were randomly sampled from the same population. Controls had plasma HIV RNA <400 copies/mL on ART for at least 6 months. Logistic regression was used to determine the adjusted odds of late HIV failure by 516G>T genotype.

RESULTS

After adjustment for the confounding variables age and CD4 count, the CYP2B6 516 T-allele was protective against late HIV virologic breakthrough, adjusted OR 0.70; 95% CI: 0.50 to 0.97.

CONCLUSION

The CYP2B6 516 T-allele was protective against late virologic breakthrough in patients with initial (6 month) HIV RNA suppression on EFV-based ART. Future studies are needed to assess long-term viral benefits of identifying and offering EFV containing ART to black African HIV-infected patients with CYP2B6 T-alleles, especially given the wider availability of a single pill EFV in this setting.

Determinants of HIV Transmission Risk Among HIV-Infected Persons Engaged in Care

People living with HIV (PLWH) engaged in medical care represent an accessible group to focus HIV prevention efforts. In an analysis of 1,883 PLWH from 2007 and 2015, we determined the proportion at risk of HIV transmission and identified factors associated with HIV transmission risk using multivariable mixed effects logistic regression models with random intercepts. HIV transmission risk was defined by an HIV viral load > 1,500 copies/mL and self-reported unprotected sex. We found that 174 (9.2%) individuals were at risk for HIV transmission at least once. Factors associated with HIV transmission risk included younger age (adjusted OR [95% CI] per decade decrease = 2.30 [1.84, 2.89]), illicit drug use (adjusted OR = 5.36 [3.02, 9.56]), depression (adjusted OR = 1.88 [1.10, 3.21]), and education <12th grade (adjusted OR = 2.05 [1.15, 3.67]). Thus, nearly 1 in 10 HIV-infected individuals engaged in care between 2007 and 2015 were potentially at risk of transmitting HIV. Behavioral interventions to decrease HIV transmission should focus on younger, less educated patients who are depressed and actively using illicit drugs.