Cannabis Expectancies as a Mediator in the Relationship Between Cannabis Use and Psychiatric Symptoms in Women With Post-traumatic Stress Disorder (PTSD) Symptoms.

Objective This study examined whether cannabis expectancies mediate the relationship between lifetime cannabis use and symptoms of anxiety or depression among women who screened positive for post-traumatic stress disorder (PTSD). Method A total of 271 women completed an online survey assessing PTSD symptoms, lifetime cannabis use, anxiety and depression symptoms, and cannabis expectancies. Mediation analyses evaluated whether positive and negative cannabis expectancies explained the associations between lifetime cannabis use and anxiety or depression. Results The sample was predominantly White (238, 85%), with a mean age of 52.5 years (Mean±SD=12.2). Positive cannabis expectancies mediated the relationship between lifetime cannabis use and anxiety [indirect effect=0.35, Bootstrapped standard error of the effect estimate (BootSE)=0.15, 95% confidence interval (CI)=0.076 to 0.664] and depression (indirect effect=0.45, BootSE=0.19, 95% CI=0.12 to 0.88) such that women with longer cannabis use histories reported higher positive expectancies and higher levels of anxiety and depression. Conclusions Positive beliefs about cannabis's anxiolytic and antidepressant effects may influence both the duration of use and psychological outcomes among women with PTSD. These findings highlight the role of expectancies in shaping the mental health impact of cannabis use in this population.