HIV This Week

Malta M, Strathdee SA, Magnanini MM, Bastos FI. Adherence to antiretroviral therapy for human immunodeficiency virus/acquired immune deficiency syndrome among drug users: a systematic review. Addiction 2008;103(8):1242-57.

Adherence to highly active antiretroviral therapy (HAART) is a key predictor of survival for human immunodeficiency virus (HIV)-infected people. Suboptimal adherence among marginalized populations such as HIV-positive drug users could be associated with clinical failure and the emergence of viral resistance. Malta and colleagues aimed to conduct a systematic review of studies assessing adherence to HAART among HIV-positive drug users and identify factors associated with non-adherence to HIV treatment. Seven electronic databases were searched for peer-reviewed papers published in English, French, Spanish or Portuguese, from 1996 to 2007. Studies were excluded if they presented only qualitative data, were reviews themselves or assessed other populations without disaggregating data on people who use drugs. Findings on adherence were extracted and summarized. Forty-one studies were considered, which studied a total of 15 194 patients, the majority of whom were HIV-positive drug users (n = 11 628, 76.5%). Twenty-two studies assessed adherence using patient self-reports, eight used pharmacy records, three used electronic monitoring [i.e. Medication Event Monitoring Systems caps], six studies used a combination of patient self-report, clinical data, and Medication Event Monitoring Systems caps, and two analyzed secondary data. Overall, active substance use was associated with poor adherence, as well as depression and low social support. Higher adherence was found in patients receiving care in structured settings (e.g. directly observed therapy) and/or drug addiction treatment (especially substitution therapy). While lower than other populations-especially among users of stimulants, incarcerated drug users and patients with psychiatric comorbidities-adherence to HAART among HIV-positive people who use drugs can be achieved. Better adherence was identified among those engaged in comprehensive services providing HIV and addiction treatment with psychosocial support.

Editors’ note: This is the first systematic review summarising the growing body of research on adherence to antiretroviral treatment among drug users. As with other populations, self-reported adherence tended to be higher than other adherence measurements. The structured daily routines of substitution therapy or directly observed treatment, higher self-esteem and self-efficacy, and positive patient-provider relationships made adherence more likely. Non-coercive, comprehensive HIV management and care assists traditionally marginalized patients to access, accept, and adhere to complex therapeutic regimens. All 41 studies considered in this review were from high-income countries. Similar studies are urgently needed in the developing and transitional countries that have experienced the largest HIV epidemics among drug users in recent years.