Cannabis and Mental Health: Adverse Outcomes and Self-Reported Impact of Cannabis Use by Mental Health Status

Abstract

Background: Cannabis can induce negative outcomes among consumers with mental health conditions. This study examined medical help-seeking behavior, patterns of adverse effects, and perceived impacts of cannabis among consumers with and without mental health conditions. Methods: Data came from the International Cannabis Policy Study, via online surveys conducted in 2018. Respondents included 6,413 past 12-month cannabis consumers aged 16–65, recruited from commercial panels in Canada and the US. Regression models examined differences in adverse health effects and perceived impact of cannabis among those with and without self-reported past 12-month experience of anxiety, depression, PTSD, bipolar disorder, psychosis. Results: Overall, 7% of past 12-month consumers reported seeking medical help for adverse effects of cannabis, including panic, dizziness, nausea. Help-seeking was greater for those with psychosis (13.8%: AOR = 1.78; 1.11–2.87), depression (8.9%: AOR = 1.57; 1.28–1.93), and bipolar disorder (10.1%: AOR = 1.53; 1.44–2.74). Additionally, 54.1% reported using cannabis to manage symptoms of mental health, with higher rates among those with bipolar (90.8%) and PTSD (90.7%). Consumers reporting >1 condition were more likely to perceive positive impacts on friendships, physical/mental health, family life, work, studies, quality of life (all p < .001). Consumers with psychosis were most likely to perceive negative effects across categories. Conclusion: For conditions with substantial evidence suggesting cannabis is harmful, greater help-seeking behaviors and self-perceived negative effects were observed. Consumers with mental health conditions generally perceive cannabis to have a positive impact on their lives. The relationship between cannabis and mental health is disorder specific and may include a combination of perceived benefits and harms.

Keywords:

• Cannabis
• marijuana
• mental health
• adverse effects
• health outcomes

Declaration of interest

The authors report no conflict of interest.

Additional information

Funding

This study was supported by a Canadian Institutes of Health Research (CIHR) Project Bridge Grant (PJT-153342) and a CIHR Project Grant. Additional support was provided by a Public Health Agency of Canada-CIHR Chair in Applied Public Health (Hammond). The funding source had no involvement in project implementation or the preparation of this manuscript.