A Longitudinal Analysis of Cannabis Use and Mental Health Symptoms among Gay, Bisexual, and Other Men Who Have Sex with Men in Vancouver, Canada

BACKGROUND:Cannabis use, anxiety, and depression are common among gay, bisexual, and other men who have sex with men (gbMSM) and some report using cannabis to manage mental health symptoms.METHODS:Sexually-active gbMSM aged ≥16 years were recruited into a longitudinal cohort through respondent-driven sampling and completed study visits every six months. Data on demographics, drug use, and anxiety and depression symptoms were collected via a self-administered computer-based survey. A study nurse determined previous mental health diagnoses and treatment. Using multivariable generalized linear mixed models, we examined factors associated with regular cannabis use (≥weekly in the previous 3 months) and, among individuals who reported anxiety or depression/bipolar diagnoses, factors associated with moderate/severe anxiety or depression symptoms.RESULTS:Of 774 participants (551 HIV-negative, 223 HIV-seropositive), 250 (32.3%) reported regular cannabis use, 200 (26.4%) reported ever being diagnosed with anxiety, and 299 (39.3%) reported ever being diagnosed with depression or bipolar disorder at baseline. Regular cannabis use was positively associated with HIV-seropositivity (aOR = 2.23, 95%CI:1.40-3.54) and previous mental health diagnosis (aOR = 1.52, 95%CI: 1.00-2.31, p = 0.05). Among those previously diagnosed with anxiety or depression/bipolar disorder, regular cannabis use was not associated with moderate/severe anxiety (aOR = 1.16, 95%CI:0.69-1.94) or depression symptoms (aOR = 0.96, 95%CI:0.59-1.58), respectively.LIMITATIONS:Because of observational study design, we are unable to determine absolute effect.CONCLUSIONS:Regular cannabis use was more likely among HIV-positive gbMSM and those previously diagnosed with a mental health disorder. No association was found between regular cannabis use and severity of anxious or depressive symptoms among those diagnosed with these conditions.