Background: Limited research examines depressive symptoms, alcohol use, and social support among HIV-infected people who inject drugs. Objectives: Using longitudinal data, we investigated whether perceived social support moderates the relationship between depressive symptoms and alcohol use among HIV-infected men who inject drugs in Vietnam. Methods: Data were collected from participants (N = 455; mean age 35 years) in a four-arm randomized controlled trial in Thai Nguyen, Vietnam. Data were collected at baseline, 6, 12, 18, and 24 months with 94% retention excluding dead (N = 103) or incarcerated (N = 37) participants. Multilevel growth models were used to assess whether: (1) depressive symptoms predict when risk of alcohol use is elevated (within-person effects); (2) depressive symptoms predict who is at risk for alcohol use (between-person effects); and (3) within- and between-person perceived social support moderates the depressive symptoms-alcohol relationship. Results: Participants reported high but declining levels of depressive symptoms and alcohol use. Participants with higher depressive symptoms drank less on average (B = -0.0819, 95% CI -0.133, -0.0307), but within-person, a given individual was more likely to drink when they were feeling more depressed than usual (B = 0.136, 95% CI 0.0880, 0.185). The positive relationship between within-person depressive symptoms and alcohol use grew stronger at higher levels of within-person perceived social support. Conclusions: HIV-infected men who inject drugs have increased alcohol use when they are experiencing higher depressive symptoms than usual, while those with higher average depressive symptoms over time report less alcohol use. Social support strengthens the positive relationship between within-person depressive symptoms and alcohol use.
Keywords: Depression; HIV/AIDS; Vietnam; alcohol use; people who inject drugs; social support.