Self-efficacy and ability to read as factors associated with antiretroviral therapy adherence in an HIV-infected population.

Determining the barriers and facilitators of antiretroviral adherence among former and current substance users may be useful in the creation of successful interventions that target this hard-to-reach population. We performed a cross-sectional study of HIV-infected patients (N = 123) prescribed antiretroviral therapy at four Chicago healthcare venues. Bivariate and multivariable analyses were performed to determine factors associated with non-adherence based on definitions of non-adherence (any missed doses) within the past 4-day, 14-day, and 1-month time periods. Factors consistently associated with non-adherence in bivariate and multivariate analyses, regardless of duration of non-adherence definition, were lower confidence in taking medication consistently and less self-reported ability to read. These data reveal the importance of self-efficacy and ability to read (rather than specific knowledge of CD4 and viral load definitions) in the design of interventions in a population of HIV-infected persons with significant substance use.