Sex Differences in the Association Between Cannabis Use and Suicidal Ideation and Attempts, Depression, and Psychological Distress Among Canadians

Background: Depression, anxiety, and substance use disorders are leading causes of morbidity worldwide. The most commonly used illicit substance is cannabis and there is some evidence that the association between cannabis use and poor mental health is more pronounced among females compared with males. This analysis examines sex differences in the association between cannabis use and major depressive episode (MDE), suicidal thoughts and attempts, and psychological distress. Methods: This study uses data from the 2002 and 2012 Canadian Community Health Survey's Mental Health Component, repeated cross-sectional surveys of nationally representative samples of Canadians 15 years of age and older (n = 43,466). Linear and binary logistic regressions were performed, applying weighting and bootstrapping. Results: There were significant sex differences in the strength of the association between cannabis use and suicidal thoughts and attempts and psychological distress, but not MDE. Females who reported using cannabis occasionally (defined as 1 to 4 times a week) reported higher levels of psychological distress than their male counterparts. Females who reported using regularly (defined as more than once per week) reported higher levels of psychological distress and were more likely to report suicidal thoughts and attempts. Conclusions: Future research is needed to further our understanding of the nature of these sex differences. Public health messaging should incorporate being female as a potential risk factor for the co-occurrence of cannabis use and emotional problems, particularly at higher frequencies of use. Clinicians should also be aware of this association to better inform integrated mental health and substance use screening, discussions, and care, particularly for female patients.