Mental Health and Cognition in Older Cannabis Users: a Review


  • Blanca E. Vacaflor McGill University
  • Olivier Beauchet Sir Mortimer B. Davis–Jewish General Hospital, McGill University
  • G. Eric Jarvis McGill University
  • Alessandra Schiavetto McGill University
  • Soham Rej McGill University



aged, frail elderly, cannabis, marijuana smoking, marijuana use, marijuana abuse, medical marijuana



The impact of cannabis use on mental health and cognition in older adults remains unclear. With the recent legalization of cannabis in Canada, physicians will need up-to-date infor­mation about the mental and cognitive effects of cannabis use in this specific population.


A narrative review was conducted to summarize the literature on mental health and cognitive effects of cannabis use in older adults using Medline (OvidSP).


A total of 16 studies were identified, including nine cross-sectional studies on mental health comorbidities reported by older cannabis users. The self-reported prevalence of mental and substance use disorders is approximately two to three times higher in older adults who report past-year cannabis use, compared to older adults who report using more than one year ago or never using. The remaining seven clinical trials found that short-term, low-dose medical cannabis was generally well-tolerated in older adults without prior serious mental illness. However, mental/cognitive adverse effects were not systematically assessed.


Although preliminary findings suggests that low-dose, short-term medical cannabis does not carry significant risk of serious mental health and cognitive adverse effects in older adults without prior psychiatric history, epidemiological studies find a correlation between past-year cannabis use and poor mental health outcomes in community-dwelling older adults. These findings may indicate that longer term cannabis use in this population is detrimental to their mental health, al­though a direct causal link has not been established. Larger, longitudinal studies on the safety of medical cannabis in older adults are needed.


Download data is not yet available.




How to Cite

Vacaflor BE, Beauchet O, Jarvis GE, Schiavetto A, Rej S. Mental Health and Cognition in Older Cannabis Users: a Review. Can Geriatr J [Internet]. 2020 Sep. 1 [cited 2023 Mar. 29];23(3):237-44. Available from:



Systematic Reviews/Meta-analysis