Suicidal Ideation in Medicinal Cannabis Patients: A 12-Month Prospective Study.

Objective: To document the prevalence and correlates of suicidal ideation (SI) among individuals seeking cannabis-based medicinal products (CBMPs); to test whether SI declines or intensifies after three months of CBMP treatment and to document 12-month trajectories of depression in those reporting SI and other patients.

Method: Observational data were available for 3781 patients at entry to treatment, 2112 at three months and 777 for 12 months. Self-reported depressed mood and SI were assessed using items from the PHQ-9. Additional data included sociodemographic characteristics and self-reported well-being.

Results: 25% of the sample reported SI at treatment entry and those with SI had higher levels of depressed mood (mean = 17.4 vs. 11.3; F_(1,3533) = 716.5, p < .001) and disturbed sleep (mean = 13.8 vs. 12.2, F_(1,3533) = 125.9, p < .001), poorer general health (mean = 43.6 vs. 52.2, F_(1,3533) = 118.3, p < .001) and lower quality of life (mean = 0.44 vs. 0.56 (F_(1,3533) = 118.3, p < .001). The prevalence of SI reduced from 23.6% to 17.6% (z = 6.5, p < .001) at 3 months. Twelve-month follow-up indicated a substantial reduction in depressed mood with this reduction being more pronounced in those reporting SI (mean _(baseline) = 17.7 vs. mean (12 months) = 10.3) than in other patients (mean _(baseline) = 11.1 vs. mean _{(12 months)} = 7.0).

Conclusions: SI is common among individuals seeking CBMPs to treat a range of chronic conditions and is associated with higher levels of depressed mood and poorer quality of life. Treatment with CBMPs reduced the prevalence and intensity of suicidal ideation.