Development of a Behavioral Economic Intervention to Reduce HIV Risk Behaviors - Individuals aged 18–34 who engage in high-risk behaviors (hereafter IHRBs) associated with HIV transmission remain disproportionately affected by HIV in the United States. There are many effective ways to prevent HIV, including daily oral PrEP. However, PrEP adherence rates among IHRBs consistently fall short of the optimal adherence thresholds. Methamphetamine use is associated with PrEP nonadherence. Engaging in safe sex (such as consistent condom use) is another effective HIV prevention method. Yet, methamphetamine, often used by some IHRBs during sex, makes people less cautious and more likely to engage in sexual risk behaviors (SRBs, e.g., sex without a condom) increasing the risk of HIV transmission. Taken together, PrEP nonadherence, methamphetamine use and engaging in SRBs all represent suboptimal choices that fit into the behavioral economic concepts of preferring immediate rewards over future benefits (delayed discounting) and overvaluation of rewards (demand). Past studies indicate that people who are not adherent to medications, those who use drugs and those who engage in SRBs often have high levels of delayed discounting and demand. Therefore, an intervention targeting delayed discounting and demand may also positively benefit PrEP nonadherence, methamphetamine use and SRBs. Episodic Future Thinking (EFT) is a novel intervention that has shown promising results in improving delayed discounting, demand, substance use, and medication adherence but has not been tested among IHRBs. The current project aims are to refine (Aim 1) and assess (Aim 2) the feasibility and acceptability of EFT for improving delayed discounting, demand, PrEP nonadherence, methamphetamine use, and SRBs among IHRBs. In Aim 1 (Phase 1), we will conduct formative evaluation of the EFT through semi-structured interviews with N=10 participants who report PrEP nonadherence, methamphetamine use, and recent sex without a condom in the past three months. Feedback will inform refinements to the EFT intervention. In Aim 1 (Phase 2), we will use findings from Phase 1 to modify elements of the EFT, resulting in a refined EFT. In Aim 2, we will conduct a six-month pilot randomized controlled trial comparing EFT versus a control condition (brief information and supportive counseling) in a sample of 60 IHRBs, using a 1:1 randomization to each group. EFT and control condition will be delivered on participants smartphone using an ecological momentary intervention platform. Primary outcomes will be the feasibility, and acceptability of the EFT intervention, alongside preliminary efficacy of the EFT on improving delayed discounting, demand, PrEP nonadherence, methamphetamine use and SRBs. Findings from this study will provide preliminary data and lay the groundwork for conducting a larger-scale (R01) trial to formally determine efficacy.
