Adherence to antiretroviral therapy in adolescents living with HIV: systematic review and meta-analysis

OBJECTIVE: Adolescent and young adult (AYA) populations (12–24 years) represent over 40% of new HIV infections globally. Adolescence is sometimes characterized by high-risk sexual behaviour and a lack of engagement with healthcare services that can affect adherence to antiretroviral therapy (ART). Despite adherence to ART being critical in controlling viral replication, maintaining health and reducing onward viral transmission, there are limited data on ART adherence amongst AYA globally. We undertook a systematic review and meta-analysis of published studies reporting adherence to ART for AYA living with HIV. DESIGN AND METHODS: Searches included Embase, Medline and PsychINFO databases up to 14 August 2013. Eligible studies defined adequate adherence as at least 85% on self-report or undetectable blood plasma virus levels. A random effects meta-analysis was performed and heterogeneity examined using meta-regression. RESULTS: We identified 50 eligible articles reporting data from 53 countries and 10 725 patients. Using a pooled analysis of all eligible studies, 62.3% [95% confidence interval (CI) 57.1–67.6; I(2) : 97.2%] of the AYA population were adherent to therapy. The lowest average ART adherence was in North America [53% (95% CI 46–59; I(2) : 91%)], Europe [62% (95% CI 51–73; I(2) : 97%)] and South America [63% (95% CI 47–77; I(2) : 85%] and, with higher levels in Africa [84% (95% CI 79–89; I(2) : 93%)] and Asia [84% (95% CI 77–91; I(2) : 0%]. CONCLUSION: Review of published literature from Africa and Asia indicate more than 70% of HIV-positive AYA populations receiving ART are adherent to therapy and lower rates of adherence were shown in Europe and North America at 50–60%. The global discrepancy is probably multifactorial reflecting differences between focused and generalised epidemics, access to healthcare and funding.