Model-Based Methods to Translate Adolescent Medicine Trials Network for HIV/AIDS Interventions Findings Into Policy Recommendations: Rationale and Protocol for a Modeling Core (ATN 161)

Projecting the Clinical and Economic Impacts of Changes to HIV Care Among Adolescents and Young Adults in the United States: Lessons From the COVID-19 Pandemic

BACKGROUND

During the COVID-19 pandemic, many US youth with HIV (YHIV) used telehealth services; others experienced disruptions in clinic and antiretroviral therapy (ART) access.

METHODS

Using the Cost-effectiveness of Preventing AIDS Complications (CEPAC)-Adolescent HIV microsimulation model, we evaluated 3 scenarios: 1) Clinic: in-person care; 2) Telehealth: virtual visits, without CD4 or viral load monitoring for 12 months, followed by return to usual care; and 3) Interruption: complete care interruption with no ART access or laboratory monitoring for 6 months (maximum clinic closure time), followed by return to usual care for 80%. We assigned higher 1-year retention (87% vs 80%) and lower cost/visit ($49 vs $56) for Telehealth vs Clinic. We modeled 2 YHIV cohorts with non-perinatal (YNPHIV) and perinatal (YPHIV) HIV, which differed by mean age (22 vs 16 years), sex at birth (85% vs 47% male), starting CD4 count (527/μL vs 635/μL), ART, mortality, and HIV-related costs. We projected life months (LMs) and costs/100 YHIV over 10 years.

RESULTS

Over 10 years, LMs in Clinic and Telehealth would be similar (YNPHIV: 11 350 vs 11 360 LMs; YPHIV: 11 680 LMs for both strategies); costs would be $0.3M (YNPHIV) and $0.4M (YPHIV) more for Telehealth than Clinic. Interruption would be less effective (YNPHIV: 11 230 LMs; YPHIV: 11 620 LMs) and less costly (YNPHIV: $1.3M less; YPHIV: $0.2M less) than Clinic. Higher retention in Telehealth led to increased ART use and thus higher costs.

CONCLUSIONS

Telehealth could be as effective as in-person care for some YHIV, at slightly increased cost. Short interruptions to ART and laboratory monitoring may have negative long-term clinical implications.

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.

Implementation determinants and mechanisms for the prevention and treatment of adolescent HIV in sub-Saharan Africa: concept mapping of the NIH Fogarty International Center Adolescent HIV Implementation Science Alliance (AHISA) initiative

INTRODUCTION

Adolescent HIV prevention and treatment is a high priority for youth healthcare in sub-Saharan Africa.

METHODS

This study employed concept mapping to identify factors that impact the implementation of HIV prevention and intervention programs for adolescents in sub-Saharan Africa. Key stakeholders including researchers, policymakers, and non-governmental organization (NGO) personnel constituting membership of the NIH-sponsored Adolescent HIV Prevention and Treatment Implementation Science Alliance responded to the question: "In your experience, what factors have facilitated or hindered implementation of evidence-based HIV prevention or treatment for adolescents in sub-Saharan Africa?" Participants generated statements in response to the focus question, sorted them into thematically relevant groups, and rated each statement on its importance and changeability.

RESULTS

Through data analyses and participant feedback, 15 distinct themes were derived. "Workforce/Workflow" and "HIV Stigma and Adolescent Development" were rated highest for importance, and "Threshold Conditions for Treatment" and "Structure of Implementation Efforts" were rated most changeable.

CONCLUSIONS

Understanding implementation science determinants and mechanisms can facilitate the uptake of successful implementation and sustainment strategies for the prevention and treatment of HIV in a given context. We placed determinants and mechanisms within the Exploration, Preparation, Implementation, Sustainment (EPIS) framework to provide greater contextual integration with broader theories in implementation science. Implementers across multiple disciplines can use these findings to improve the scale-up of evidence-based practices for adolescent HIV prevention and treatment in sub-Saharan Africa. Implementation approaches that consider the determinants and mechanisms identified in this study and integrated in implementation frameworks will likely have utility for other health conditions and contexts.

Research Priorities to End the Adolescent HIV Epidemic in the United States: Viewpoint

Youth represent 21% of new HIV diagnoses in the United States. Gay, bisexual, and transgender (GBT) youth, particularly those from communities of color, and youth who are homeless, incarcerated, in institutional settings, or engaging in transactional sex are most greatly impacted. Compared with adults, youth have lower levels of HIV serostatus awareness, uptake of antiretroviral therapy (ART), and adherence. Widespread availability of ART has revolutionized prevention and treatment for both youth at high risk for HIV acquisition and youth living with HIV, increasing the need to integrate behavioral interventions with biomedical strategies. The investigators of the Adolescent Medicine Trials Network for HIV/AIDS Interventions (ATN) completed a research prioritization process in 2019, focusing on research gaps to be addressed to effectively control HIV spread among American youth. The investigators prioritized research in the following areas: (1) innovative interventions for youth to increase screening, uptake, engagement, and retention in HIV prevention (eg, pre-exposure prophylaxis) and treatment services; (2) structural changes in health systems to facilitate routine delivery of HIV services; (3) biomedical strategies to increase ART impact, prevent HIV transmission, and cure HIV; (4) mobile technologies to reduce implementation costs and increase acceptability of HIV interventions; and (5) data-informed policies to reduce HIV-related disparities and increase support and services for GBT youth and youth living with HIV. ATN’s research priorities provide a roadmap for addressing the HIV epidemic among youth. To reach this goal, researchers, policy makers, and health care providers must work together to develop, test, and disseminate novel biobehavioral interventions for youth.

The ongoing HIV epidemic in American youth: challenges and opportunities

The incidence of human immunodeficiency virus (HIV) infection has been decreasing in the United States overall, except among youth, and in particular among Black and Latinx young men who have sex with men (MSM). In this review we summarize key drivers of the HIV epidemic among youth, as well as novel interventions geared specifically towards combating the epidemic among high-risk populations. Many factors driving the HIV epidemic among youth are related to systemic inequities, including lack of access to healthcare, inadequate education, and internalized and experience homophobia and racism. Developmentally, youth may feel that they are invulnerable and be willing to engage in risks. Moreover, HIV is often invisible for youth given advances in treatment and community stigma, limiting open discussion of risk and new preventive modalities. Outcomes from the HIV treatment cascade suggest that youth are less likely to be aware of their HIV infection status, less likely to link to and be engaged in care, and less likely to be virologically suppressed than older MSM and other populations of people living with HIV. Importantly, pre-exposure prophylaxis (PrEP) has been shown to be an effective tool for prevention of HIV infection that also appears to have disproportionately poor uptake among youth. Barriers to PrEP utilization appear to be quite heterogeneous, and include patient-, provider-, and structural-level barriers. Interventions important in improving HIV prevention will thus have to be multipronged and developed for culturally diverse populations. Cognitive behavioral therapy-based interventions are promising strategies as they are able to address a diverse array of barriers. New formulations of PrEP will also likely be instrumental in improving adherence. Since youth spend considerable amounts of time accessing digital media, the deployment of apps and other mobile phone-based interfaces offer unique opportunities to increase education and to facilitate HIV prevention for at risk youth. Multiple studies are underway to better inform the optimal delivery of treatment and prevention services for this complex and diverse population, and include novel sociobiological interventions and new modes of medication delivery that may lend themselves to overcoming obstacles specific to youth.