4 - (IOP 29) Tailored Motivational Interviewing Reduces Substance Use and Sexual Risk Taking Among Partnered Sexual Minority Men Aged 18 to 35: Results of the PARTNER Study

The development of scalable interventions that address the intersection of drug use and sexual HIV transmission risk for younger adult sexual minority men (SMM) who have \primary relationship partners is a public health priority. SMM account for 67% of new HIV infections in the US and as many as 68% of new HIV infections in this population are transmitted sexually between primary relationship partners. Those under 36 are at greatest risk. Compounding HIV risk, SMM are more likely to use drugs and develop problems associated with dependence compared to their heterosexual counterparts. In addition to direct health risks, drug use among SMM is a well-established correlate of sexual HIV transmission risk.

Most behavioral interventions addressing drug use and associated HIV transmission risk among SMM in relationships have focused on couples. Although valuable, the requirements of dyadic interventions may limit the reach of these interventions. Guided by interdependence theory our team developed the PARTNER intervention -- 4 sessions of motivational interviewing (MI) that incorporate cognitive behavioral skill building components to enhance relationship quality and communication skills.

A randomized controlled trial (conducted between January, 2018 and February, 2024) evaluated the efficacy of the PARTNER intervention to reduce cannabis and illicit drug use, increase PrEP uptake, and reduce sexual HIV transmission risk behavior. Participants included 196 cisgender, younger adult (aged 18 to 35) SMM in relationships with other men. All reported drug use and condomless sex with a casual partner or serodiscordant main partner in the past 30 days. Baseline assessments included a survey battery and timeline follow-back (TLFB) interview of drug use and sexual behavior. Self-reported behavior was corroborated by urine drug screen and bacterial STI testing. Participants were randomized to either the experimental PARTNER intervention or a time-and-attention matched education control. They completed follow-ups 3, 6, 9, and 12-months post baseline.

Results of Latent Growth Curve analysis indicated that the PARTNER intervention achieved significant immediate reductions in illicit drug use among those with low-levels of communication skills or high levels of relationship satisfaction at baseline. In addition, participants in the PARTNER intervention displayed a trajectory of increasing PrEP uptake that was significantly more positive compared to the control condition (for whom PrEP uptake declined over time). Effects were of moderate size (0.5 to 1.0 standard deviation differences between conditions). Between group differences for cannabis and sexual HIV transmission risk behavior were non-significant.

Brief (4-session) MI tailored to address the needs of partnered SMM demonstrated the potential to improve drug use and HIV prevention outcomes when compared to a highly competitive control condition. Those with relatively poor communication skills may have derived the greatest benefit from skill building components. Those with better relationship quality may have had more partner support for behavior change. Implications for practice and adaptations that might enhance the durability of effects are discussed.