Four types of barriers to adherence of antiretroviral therapy are associated with decreased adherence over time.

The objectives of this study were to understand how different types of barriers to adherence to antiretroviral therapy (ART) were related and their differential impact on objectively measured adherence over time. Data from 151 patients taking ART were used to describe four sub-types of self-reported adherence barriers: medication and health concerns (MHC), stigma (S), family responsibilities (FR), and problems with schedule and routine (PSR). Generalized linear models with generalized estimating equations (GEE) were used to examine the impact of barriers on adherence over time. The sample was 23 % female, mean age 42 years, with 26 % African-American and 20 % Hispanic. The overall average adherence was 73 %. Patients reported at least one PSR barrier in 66 % of study visits, MHC in 40 %, S in 17 %, and FR in 6 %. In 40 % of visits, patients reported two or more barrier sub-types. There were statistically significant (p ≤ 0.05) decreases of 3.9, 2.5, and 2.4 in percent adherence, for MHC, PSR, and S, respectively, per unit increase in barrier score. Interventions to address different types of patient-identified barriers to ART adherence using targeted approaches are needed.