A systematic review and meta-analysis has identified three-fold higher rates of major depression and generalized anxiety disorder (GAD) among people with cannabis use disorder. Researchers reported their findings online in the Journal of Affective Disorders.
“Studies have shown a high degree of comorbidity between cannabis use disorder and other mental illnesses. However, there is a paucity of research on the comorbidity between cannabis use disorder with major depression and generalized anxiety disorder,” wrote lead author Vivian N. Onaemo, PhD, of the Government of Saskatchewan Ministry of Health in Regina, Canada, and colleagues.
“This systematic review with meta-analysis aimed to assess the prevalence and strength of association between comorbid cannabis use disorder with major depression and generalized anxiety disorder.”
Researchers identified 8 publications based on 6 nationally representative epidemiological surveys, most conducted in the United States and Australia, and extracted 12-month and lifetime comorbidity estimates for meta-analysis.
Cannabis use disorder was associated with a three-fold increase in the risk of major depression, according to the study. According to Psychiatric News Alert coverage of the study, researchers hypothesized the 3.22 heightened odds of major depression in people with cannabis use disorder could be due to changes in brain chemistry caused by cannabis use or a predisposition of substance use among some people with mental health disorders.
Similarly, cannabis use disorder was linked with a nearly three-fold increase in GAD risk. The 2.99 higher odds of GAD with cannabis use disorder could be caused by chronic cannabis use, researchers speculated.
Regardless of the pathway, “a vicious cycle may be at play where each disorder maintains or exacerbates the other,” the Psychiatric News Alert report quoted from the study.
“Implementation of evidence-based policy interventions with effective, integrated management of comorbid cannabis use disorders with psychiatric disorders may contribute to positive patient outcomes,” researchers advised.
Onaemo VN, Fawehinmi TO, D’Arcy C. Comorbid cannabis use disorder with major depression and generalized anxiety disorder: a systematic review and meta-analyses of nationally representative epidemiological surveys. Journal of Affective Disorders. 2020 December 16;[Epub ahead of print].