UC San Diego

Rationale: Sexual risk-taking often occurs in the context of methamphetamine use and promotes HIV transmission. Methamphetamine and HIV preferentially impact the frontostriatal circuits, resulting in frontal systems dysregulation and risky behaviors. Interventions for risky sex often target motivation/intentions to change. However, safe intentions do not always translate to safe behaviors. In order to develop more effective interventions for resolving this intention-behavior discrepancy, it is important to better understand what factors affect this relationship. Design: The sample included 234 adults recruited from the community. It was hypothesized that disinhibition, executive dysfunction, HIV, and methamphetamine dependence would moderate the relationship between intentions and behavior (evaluated through multiple linear regressions), and intentions would mediate the relationship between apathy and behavior (evaluated through bootstrapping). Results: As hypothesized disinhibition and methamphetamine dependence each were significant moderators (ps < .05), such that for those without methamphetamine dependence or disinhibition, safer intentions predicted safer behaviors (ps < .001), however, for those with either methamphetamine dependence or disinhibition difficulties, intentions no longer predicted behaviors (ps > .05). There was a significant three-way interaction between intentions, executive dysfunction, and HIV, such that for those without HIV, executive functioning did not alter the relationship between intentions and behavior (p = .130); however, for those with HIV, better executive functioning resulted in a positive relationship between intentions and behaviors (p = .005) while those with worse executive functioning no longer implemented their intentions (p = .845). Finally, intentions mediated the relationship between apathy and behaviors (CI = [.006, .130]). Conclusions: Disinhibition, executive functioning, methamphetamine dependence, and HIV are important factors that interfere with one’s ability to implement safe intentions. Additionally, apathy dampens an individual’s desire to behave safely thereby resulting in problematic risk. These findings identify possible areas of intervention when trying to reduce sexual risk-taking behaviors. Implementing substance use treatment and cognitive rehabilitation (targeting impulsivity and executive dysfunction) as well as finding external motivators when apathy is present may be helpful interventions for improving a patient’s ability to implement their intended behaviors and increase safety during sex.