Cannabis Use and its Relation to Psychological Disorders including Anxiety and Depression

Cannabis has become a very popular drug world wide, and has even been legalized in some countries. Avid cannabis users love the benefits that cannabis can provide, and medical professionals even prescribe it to patients as a natural pain remedy. While cannabis is widely known to calm people down and relieve physical pain, it has been shown to complicate and worsen symptoms in patients with mental disorders including anxiety and depression.

A study published in the Journal of the American Academy of Child & Adolescent Psychiatry followed 3,239 Australian young adults from birth to age 21 and data on their anxiety and depression and cannabis use were collected over time. The study found that “those who started using cannabis before age 15 years and used it frequently at 21 years were more likely to report symptoms of AD in early adulthood (odds ratio 3.4; 95% CI 1.9-6.1)” (Hayatbakhsh et al., 2007). Furthermore, a study published in the BMJ (British Medical Journal) followed 1,601 students ages 14-15 for seven years to determine if cannabis use during their adolescence would lead to higher rates of anxiety and depression later on in life. The study found that “Daily use in young women was associated with an over fivefold increase in the odds of reporting a state of depression and anxiety after adjustment for intercurrent use of other substances (odds ratio 5.6, 95% confidence interval 2.6 to 12). Weekly or more frequent cannabis use in teenagers predicted an approximately twofold increase in risk for later depression and anxiety (1.9, 1.1 to 3.3) after adjustment for potential baseline confounders” (Patton et al., 2002). Therefore, it is clear that young people who use cannabis may have a greater chance of having anxiety or depression in their lives.

A study published in the Social Psychiatry and Psychiatric Epidemiology consisted of analyzing data from the Australian National Survey of Mental Health and Well-Being that involved cannabis use and anxiety and depression rates. The researchers found that “Among those with DSM-IV cannabis dependence, 14% met criteria for an affective disorder, compared to 6% of non-users; while 17% met criteria for an anxiety disorder, compared to 5% of non-users” (Degenhardt et al., 2001). Moreover, a study published in the Journal of Psychiatric Research found that after following participants of the Oregon Adolescent Depression Project, “SAD [social anxiety disorder] at study entry was associated with 6.5 greater odds of cannabis dependence… at follow-up after controlling for relevant variables (e.g., gender, depression, conduct disorder)” (Buckner et al., 2008).

Lastly, a study published in the Frontiers in Psychiatry Journal conducted research to determine a link between cannabis use and psychiatric illnesses. As seen in the figure below, researchers found that the risk of psychiatric illness later in life is heightened when cannabis is used during adolescence (Chadwick et al., 2013).

Cannabis use during adolescence vs. risk of psychiatric illnesses (green line = cannabis-exposed, gray line = unexposed)

The amount of people who support the legalization of cannabis seems to increase every day, and supporters claim that cannabis can work wonders as a pain remedy and an all-around calming drug. However, there is a large amount of evidence that shows that cannabis can work adversely for people who struggle with psychological disorders including anxiety and depression.

Works Cited

Buckner JD, Schmidt NB, Lang AR, et al. Specificity of social anxiety disorder as a risk factor for alcohol and cannabis dependence. Journal of Psychiatric Research. Vol 42, p 230-239. 2008.

Chadwick B, Miller ML, Hurd YL. Cannabis use during adolescent development: susceptibility to psychiatric illnesses. Frontiers in Psychiatry. Vol 4, p 32-39. 2013.

Degenhardt L, Hall W, Lynskey M. The relationship between cannabis use, depression and anxiety among Australian adults: findings from the National Survey of Mental Health and Well-Being. Social Psychiatry and Psychiatric Epidemiology. Vol 36, p 219-227. 2001.

Hayatbakhsh MR, Najman JM, Jamrozik K, et al. Cannabis and Anxiety and Depression in Young Adults: A Large Prospective Study. Journal of the American Academy of Child & Adolescent Psychiatry. Vol 46, p 408-417. 2007.

Patton GC, Coffey C, Carlin JB, et al. Cannabis use and mental health in young people: cohort study. The British Medical Journal. Vol 325, p 1195-1198. 2002.