Exploring the Impact of Reduction in Methamphetamine Use on Sexual Risk Behaviors Among Men Who Have Sex with Men and Women: Findings from the ADAPT- 2 Trial.

BACKGROUND

Methamphetamine (MA) use has been linked to engaging in sexual risk behaviors (SRBs) that are associated with HIV/STIs, particularly among men who have sex with men (MSM) and men who have sex with men and women (MSMW; hereafter MSM/W). The objectives of this analysis were to determine whether reduced MA is associated with decreases in SRBs in a sample of MSM/W.

METHOD: Data came from the ADAPT- 2 trial, a randomized, double-blind, two-stage sequential parallel design trial evaluating extended-release injectable naltrexone (NTX) and oral bupropion (BUP) vs. placebo for MA use disorder. In the first 6 weeks of the trial (stage 1), participants were randomized to receive NTX-BUP or placebo. In the second 6 weeks, participants in the placebo group who did not have a treatment response were rerandomized (stage 2). For this secondary analysis, the independent variable was the number of MA-negative urine drug screens (UDS). The dependent variables included three different types of SRBs. Regression models of the independent and dependent variables were adjusted for age, race/ethnicity status, marital status, treatment assignment, and baseline SRBs.

RESULTS

Of the 151 participants, median age was 40 years and majority were non-Hispanic white (52%) and completed more than high school education (82%). Each additional MA-negative UDS was associated with a 7% (adjusted rate ratio (aRR) = 0.93; 95% CI, 0.87, 0.99) reduction in total number of sex partners in stage 2 only. Each additional MA-negative UDS was associated with a 13% (aRR = 0.87 95%; confidence interval (CI), (0.76, 0.98)) and 9% (aRR = 0.91; 95% CI, 0.84, 0.99) reduction in number of condomless sexual encounters in stage 1 and stage 2, respectively. Lastly, each additional MA-negative UDS was associated with a 16% (aRR = 0.84; 95% (CI), 0.75, 0.94)) and 27% (aRR = 0.73; 95% CI, 0.64, 0.84) reduction in number of sexual encounters when high on MA.

CONCLUSION

Our analysis showed that reductions in MA use was associated with reductions in several sexual risk behaviors associated with HIV/STI. These findings provide further support for exploring reductions in sexual risk behaviors as a clinical endpoint in future treatment interventions for MA use.