Factors Associated with Antiretroviral Medication Adherence among HIV-Positive Adults Accessing Highly Active Antiretroviral Therapy (HAART) in British Columbia, Canada

Abstract

Among those accessing treatment, highly active antiretroviral therapy (HAART) has transformed HIV into a chronic and manageable condition. However, high levels of adherence are required to derive a sustained, long-term clinical benefit. The aim of this study was to examine the predictors of adherence based on prescription refill among persons on HAART in British Columbia, Canada. This study utilizes data collected between July 2007 and January 2010, as part of the Longitudinal Investigations into Supportive and Ancillary health services (LISA) cohort, which is a study of HIV-positive persons who have accessed antiretroviral therapy (ART) in British Columbia. Participants were considered optimally adherent if they were dispensed ≥95% of their prescribed antiretrovirals. Of a total of 566 participants, only 316 (55.8%) were optimally adherent to HAART. Independent predictors of optimal adherence were increasing age (adjusted odds ratio [AOR] = 1.84, 95% confidence interval [CI]: 1.44-2.33), male gender (AOR = 1.68, 95% CI: 1.07-2.64), and being enrolled in a comprehensive adherence assistance program (AOR = 4.26, 95% CI: 2.12-8.54). Having an annual income <$15 000 (AOR = 0.47, 95% CI: 0.31-0.72) and both former and current injection drug use (AOR = 0.46, 95% CI: 0.29-0.73 and AOR = 0.35, 95% CI: 0.20-0.58, respectively) were independently associated with suboptimal (<95%) adherence. We found that women and people who inject drugs are at increased risk of being suboptimally adherent to HAART. Optimal adherence remains a significant public health and clinical goal in the context of rapidly expanding access to HAART.