(PS6-C52) Co-use of Alcohol and Cannabis Among Couples with Alcohol Use Disorder and Intimate Partner Violence

Abundant literature is clear that romantic partners significantly influence one another’s drinking behaviors, but within-couple drug use associations have rarely been examined. A related line of research indicates that substance use disorder (SUD) closely intersects with intimate partner violence (IPV): IPV is more common among those who have SUD, and SUD is a known precipitant and consequence of IPV. Cannabis is the most used drug among adults who drink, and co-use of alcohol and cannabis at the event level (i.e., simultaneous use) is also highly prevalent. Emerging evidence also suggests that cannabis use and IPV are related (Flanagan et al., 2020; Chung et al., 2021; Shorey et al., 2018; Testa et al., 2018), however, findings from the limited available data are complex. Most research to date has investigated alcohol and cannabis co-use among individuals rather than couples, and questions remain about the associations between alcohol and cannabis co-use in the context of a relationship with IPV. We sought to better understand the relation between alcohol and cannabis use among couples with alcohol use disorders (AUD) and IPV, predicting that one’s own alcohol use would be positively associated with their own and their partner’s cannabis use. Participants were 95 different-sex couples (N = 190 individuals; M_age = 34.74, SD =11.30; 71.2% white, 21.2% Black) enrolled in a randomized controlled laboratory trial. Data reported were collected at baseline. Couples reported at least one event of physical IPV in their current relationship, and at least one member of the couple had an AUD. In 56.8% of couples, both partners had an AUD. Using the Time Line Follow Back, each participant reported the number of days they used alcohol and cannabis in the past 60 days. Actor Partner Interdependence Models were used to examine alcohol and cannabis co-use at the individual and dyadic level. Men reported an average 31.48 days (SD = 21.24) of alcohol use and 17.12 days (SD = 23.97) of cannabis use. Women reported an average 25.58 days (SD = 18.19) of alcohol use and 12.31 days (SD = 21.12) of cannabis use. Regarding co-use, 51.6% (n = 49) of men and 46.3% (n = 44) of women reported at least one drinking day and at least one cannabis use day during the study period. Male partner’s days drinking alcohol showed a significant, positive association with their female partner’s days of cannabis use (b = .256, p = -.016). No other significant effects were detected. These results, albeit cross-sectional and correlational, highlight alcohol and cannabis co-use as a prevalent issue among high-risk couples such as those with IPV. However, findings were not entirely aligned with hypotheses. Importantly, co-use is associated with more negative consequences and greater acute intoxication relative to only using only alcohol or cannabis (Sokolovsky et al., 2020). Future research is needed to elucidate the impact of concordant co-use of alcohol and cannabis between partners, particularly among couples experiencing IPV. Cognitive-behavioral therapists should assess for co-use of alcohol and cannabis among patients or couples reporting relationship discord and aim to reduce the frequency of substance use and co-use. Such efforts may in turn decrease other high-risk behaviors such as IPV.