Depression and substance use, the most common comorbidities with HIV, are both associated with poor treatment outcomes and accelerated HIV disease progression. Though previous research has demonstrated short-term and follow-up success for cognitive behavioral therapy for adherence and depression (CBT-AD) on depression outcomes among patients with HIV in care and among patients with HIV in active substance abuse treatment for injection drug use (IDU), there is little information regarding possible moderating effects of active use versus abstinence on depression treatment gains. The present study aimed to examine recent substance use at treatment initiation as a moderator of the acute and maintenance effects of CBT-AD on depression. We used data from a two-arm, randomized controlled trial (N = 89) comparing CBT-AD to enhanced treatment as usual in individuals in treatment for IDU. To test whether depression at time of presentation affected outcomes, repeated-measures ANOVAs were conducted for two time frames: (1) acute phase (baseline to post-treatment) (acute) and (2) maintenance phase (baseline to 12-month follow-up). To further examine maintenance of gains, we additionally looked at post-treatment to 12-month follow-up. Depression scores derived from the clinical global impression for severity and the Montgomery-Asberg depression rating scale (MADRS) served as the primary outcome variables. Acute (baseline post treatment) moderation effects were found for those patients endorsing active drug use at baseline in the CBT-AD condition, who demonstrated the greatest reductions in MADRS scores at post-treatment (F[1,76] = 6.78, p = .01) and follow-up (F[1,61] = 5.46, p = .023). Baseline substance use did not moderate differences from post-treatment to 12-month follow-up as depression treatment gains that occurred acutely from baseline to post-treatment were maintained across both patients engaged in substance use and abstainers. We conclude that CBT-AD for triply diagnosed patients (i.e. HIV, depression, and substance dependence) is useful for treating depression for both patients with a history of substance use, as well as patients currently engaged in substance use.
Keywords: CBT-AD; HIV; depression; injection drug use.