The Role of Reward and Reinforcement in Understanding Alcohol Use Among Adults Living With HIV in South Africa

Objective: Most research investigating reinforcement in alcohol use is from high-income countries. The current study sought to understand the association of different reinforcement types (alcohol-specific reward, environmental reward, behavioral activation) with multiple measures of alcohol use and cravings among individuals living with HIV in South Africa. Method: Baseline data were obtained from a substance use clinical trial in Cape Town (N = 65). Unhealthy alcohol use was measured using the biomarker phosphatidylethanol (PEth), Alcohol Use Identification Test (AUDIT-C), average number of drinks from the timeline follow back (TLFB), and self-reported cravings. Reinforcement was measured using the proportion of income spent on alcohol (alcohol-specific reward), both subscales of the Reward Probability Index (environmental reward), and the Behavioral Activation Depression Scale (activation). Poisson and linear regression analyses were conducted. Results: Each percentage point increase in income spent on alcohol was significantly associated with PEth, RR = 1.004 [95% CI (1.001, 1.007)], which translates to a 13.6% increase in the relative risk of unhealthy alcohol use for the average person in the study. More alcohol-specific reward was significantly associated with higher scores on the AUDIT-C, higher average number of drinks on the TLFB, and more cravings. Higher activation was associated with lower scores on the AUDIT-C. Neither subscale of environmental reward was associated with model outcomes. Conclusion: Greater alcohol-specific reward and less behavioral activation were associated with more frequent and unhealthy alcohol use in this setting, but not environmental reward. Findings highlight how different reinforcement types potentially influence alcohol use in a low-resource global setting. Public Health Significance Statements More money spent on alcohol and less goal-directed behavior were associated with more alcohol use in adult drinkers living with HIV in South Africa. Identifying readily available rewarding opportunities outside of alcohol is needed in a population with very few financial resources and comorbid HIV in South Africa.