Cannabis use may be associated with suicidality in young adults - National Institutes of Health

NIH study suggests a link between cannabis use and higher levels of suicidal ideation, plan, and attempt.

An analysis of survey data from more than 280,000 young adults ages 18-35 showed that cannabis (marijuana) use was associated with increased risks of thoughts of suicide (suicidal ideation), suicide plan, and suicide attempt.

Over the same time span, the number of adults with depression also increased, as did the number of people who reported suicidal ideation or plan or who died by suicide.

civilian, noninstitutionalized population age 12 or older on cannabis use and use disorder, depression, suicidality, and other behavioral health indicators.

The researchers compared four levels of past-year cannabis use: no cannabis use; nondaily cannabis use; daily cannabis use, which was defined as use on at least 300 days per year; and presence of cannabis use disorder, which was assessed in the survey and involves meeting specific criteria for a pattern of continued cannabis use despite negative consequences.

To identify suicidality trends, the investigators separately assessed the trends in the prevalence of past-year suicidal ideation, plan, and attempt as reported in the 2008-2019 NSDUH surveys.

The results of the study indicated that even people who used cannabis nondaily, fewer than 300 days a year, were more likely to have suicidal ideation and to plan or attempt suicide than those who did not use the drug at all.

Among people without a major depressive episode, about 3% of those who did not use cannabis had suicidal ideation, compared with about 7% of those with nondaily cannabis use, about 9% of those with daily cannabis use, and 14% of those with a cannabis use disorder.

Among people with depression, 35% of people who did not use cannabis had suicidal ideation, compared to 44% of those with nondaily cannabis use, 53% of those who used cannabis daily, and 50% of those who had a cannabis use disorder.

Similar trends existed for the associations between different levels of cannabis use and suicide plan or attempt.

Moreover, the researchers found that women who used cannabis at any level were more likely to have suicidal ideation or report a suicide plan or attempt than men with the same levels of cannabis use.

Among individuals with both cannabis use disorder and major depressive episode, the prevalence of past-year suicide plan was 52% higher for women (23.7%) than men (15.6%). 

B Han, WM Compton, EB Einstein, ND Volkow. Associations of Suicidality Trends With Cannabis Use as a Function of Sex and Depression Status. JAMA Network Open. DOI: 10.1001/jamanetworkopen.2021.13025 (2021)