The association between cannabis use and romantic relationship satisfaction: The role of intensity, concordance, and sex differences

Introduction: The effect of cannabis use on romantic relationship satisfaction remains unclear, partly due to methodological shortcomings in earlier studies, such as the reliance on a single index of cannabis exposure. Methods: In this study, we explored the association between an integrated frequency-by-quantity measure of cannabis use exposure and quality of romantic relationships, while addressing possible sex differences. 110 couples completed validated questionnaires assessing cannabis use patterns, general satisfaction with relationship quality, satisfaction with the quality of sex, and perceived partner responsiveness. The effects of between-partner concordance in cannabis use intensity on relationship quality were tested using multilevel linear regression analyses. Within-partner and between-partner effects of cannabis use intensity on relationship quality, as well as possible sex differences, were tested using the Actor-Partner Interdependence Model. Results: Regression analyses indicated that a discrepancy in cannabis use intensity was negatively associated with general relationship satisfaction (β = −.19, p = .008) and with the quality of sex (β = −.16, p = .02). Dyadic analyses revealed significant Actor and Partner intensity × sex interactions related to the quality of romantic relationship. These interactions indicated that women who used cannabis at high intensity reported greater relationship satisfaction and perceived both their own and their partner's responsiveness as higher, whereas men reported the opposite. Conclusions: Cannabis use intensity may have different effects on romantic relationship satisfaction for men and women. Further research is needed to uncover the nature of these differences.