Abstract
INTRODUCTION: In the era of HIV treatment as prevention (TasP), evidence-based interventions that optimize viral suppression among people who use stimulants such as methamphetamine are needed to improve health outcomes and reduce onward transmission risk. We tested the efficacy of positive affect intervention delivered during community-based contingency management (CM) for reducing viral load in sexual minority men living with HIV who use methamphetamine. METHODS: Conducted in San Francisco, this Phase II randomized controlled trial tested the efficacy of a positive affect intervention for boosting and extending the effectiveness of community-based CM for stimulant abstinence to achieve more durable reductions in HIV viral load. From 2013 to 2017, 110 sexual minority men living with HIV who had biologically confirmed, recent methamphetamine use were randomized to receive a positive affect intervention (n = 55) or attention-control condition (n = 55). All individual positive affect intervention and attention-control sessions were delivered during three months of community-based CM where participants received financial incentives for stimulant abstinence. The 5-session positive affect intervention was designed to provide skills for managing stimulant withdrawal symptoms as well as sensitize individuals to natural sources of reward. The attention-control condition consisted of neutral writing exercises and self-report measures. RESULTS: Men randomized to the positive affect intervention displayed significantly lower log(10) HIV viral load at six, twelve and fifteen months compared to those in the attention-control condition. Men in the positive affect intervention also had significantly lower risk of at least one unsuppressed HIV RNA (≥200 copies/mL) over the 15-month follow-up. There were concurrent, statistically significant intervention-related increases in positive affect as well as decreases in the self-reported frequency of stimulant use at six and twelve months. CONCLUSIONS: Delivering a positive affect intervention during community-based CM with sexual minority men who use methamphetamine achieved durable and clinically meaningful reductions in HIV viral load that were paralleled by increases in positive affect and decreases in stimulant use. Further clinical research is needed to determine the effectiveness of integrative, behavioural interventions for optimizing the clinical and public health benefits of TasP in sexual minority men who use stimulants such as methamphetamine.