Abstract
Introduction: Depression and substance use disproportionally affect people with HIV (PWH) and are linked with poor antiretroviral (ART) adherence. However, it remains unclear whether substance use attenuates the effect of depression and adherence treatments.
Methods: The present study used data from a completed randomized controlled trial of cognitive behavioral therapy for adherence and depression (CBT-AD) revealing significant effects on adherence and depression compared to enhanced treatment as usual (ETAU) in PWH. In this study, we examined the potential moderating effects of problematic baseline substance use on differential CBT-AD treatment gains in 143 HIV-positive adults with depression on these outcomes.
Results: Acute (baseline to 4-month) three-way general linear modeling with time, condition, problematic baseline substance use, and their corresponding interactions demonstrated that substance use was not a significant moderator of adherence outcomes or depression symptoms across the two conditions. In examining three-way follow-up (4-, 8-, and 12-month) analyses, results demonstrated that substance use was not a significant moderator of adherence outcomes or depression symptoms across the two conditions. However, a significant two-way interaction between condition and substance use was found (B=12.99, p=.049), such that substance use affected adherence outcomes for participants in the ETAU condition but not those in the CBT-AD condition. In other words, individuals in the ETAU condition who used substances showed significantly lower adherence (64%) than those who did not (74%).
Discussion: CBT-AD was beneficial for PWH with depression, regardless of their substance use status at baseline. These results may provide practical information for clinicians or researchers confronting the dilemma of whether to start a psychosocial treatment for depression or adherence in PWH with comorbid substance abuse.