What do HIV-positive drug users' experiences tell us about their antiretroviral medication-taking? An international integrated literature review.

BACKGROUND AND AIMS: HIV-positive drug users' poor adherence to antiretroviral regimens can pose a significant and negative impact on individual and global health. This review aims to identify knowledge gaps and inconsistencies within the current evidence base and to measure HIV-positive drug users' adherence rates and the factors that influence their adherence. METHODS: A search of quantitative and qualitative studies in relation to HIV-positive drug users' adherence to antiretroviral treatment was performed using five databases: Applied Social Sciences Index and Abstract (ASSIA), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Medline, Embase and PsycINFO (Ovid interface). Relevant studies were retrieved based on the inclusion and exclusion criteria stated in the review. Findings were compared, contrasted and synthesized to provide a coherent account of HIV-positive drug users' adherence rates and the factors that influence their adherence. RESULTS: The proportion of HIV-positive drug users who achieved ≥ 95% adherence across the studies varied widely, from 19.3 to 83.9%. Adherence rates changed over the course of HIV treatment. The factors that influenced adherence were reported as follows: stigmatization, motivation, active drug use, accessibility and conditionality of HIV and addiction care, side effects and complexity of treatment regimens, forgetfulness and non-incorporation of dosing times into daily schedules. CONCLUSIONS: HIV-positive drug users' medication-taking is a dynamic social process that requires health professionals to assess adherence to HIV treatment on a regular basis.