During the past decade, cannabis use among US adults has increased markedly. At the same time, we’ve seen a parallel increase in suicidality (ideation, plan, attempt, and death). So are these two facts related?
That’s a big part of the question that a new government-funded study is seeking to clarify. Additionally, researchers want to learn if a person’s sex or mental health affects the association between cannabis use and suicidal thoughts.
The authors of the study admit that, at this point, the associations between cannabis use and suicidality among young adults are poorly understood. (And of course, in the absence of good information, paranoia abounds.)
For the study, researchers utilized data from the 2008-2019 National Surveys of Drug Use and Health. They examined the responses of well over 281, 000 participants between the ages of 18 and 35 who were questioned about their use of cannabis, depression, suicidal thoughts or plans, or any suicide attempts.
The study results indicated that even people who used cannabis nondaily, fewer than 300 days a year (which is still pretty frequently), were more likely to have suicidal ideation and to plan or attempt suicide than those who did not use the drug at all. These associations remained regardless of whether someone was also experiencing depression. According to study authors:
“In this study, cannabis use was associated with higher prevalence of suicidal ideation, plan, and attempt among US young adults with or without depression, and the risks were greater for women than men.”
While we cannot establish that cannabis use caused the increased suicidality we observed in this study, these associations warrant further research, especially given the great burden of suicide on young adults.
That sounds pretty damning, so let’s take a closer look at the issue.
This current study comes on the heels of other studies that have also suggested a link between cannabis use and mood disorders. One of the most recent, a study coming out of Stanford just a couple of months ago, found more suicide attempts in states with fully legal recreational marijuana laws (as opposed to states with legalized medical marijuana).
However, the Stanford study points to the regular or heavy use of high potency cannabis products (researchers found no evidence linking medical marijuana to self-harm). And interestingly, the data showed that men – not women – 21 and younger were most at risk of suicidality.
To further complicate the issue, we have studies like this one from the University of British Columbia that show that cannabis can be helpful for certain mental health disorders, like PTSD.
Specifically, the UBC study found that cannabis non-users with PTSD were about seven times more likely to have experienced a recent major depressive episode and 4.7 times more likely to have thoughts of suicide compared to cannabis non-users without PTSD, the researchers found. (Participants in this study were 15 years or older.)
So the most recent NIH study results have to be evaluated in the context of all the existing information – which at present is conflicting and hard to tease out. Senior study author and NIDA Director Nora Volkow acknowledged in a press release about the study that the study results are not cut and dried:
“While we cannot establish that cannabis use caused the increased suicidality we observed in this study, these associations warrant further research, especially given the great burden of suicide on young adults. As we better understand the relationship between cannabis use, depression, and suicidality, clinicians will be able to provide better guidance and care to patients.”
In short, more research is needed to discover how these factors are related. Certainly, these results shouldn’t be dismissed. Like any other substance with medical benefits, there may be associated risks. It’s the job of researchers to both investigate and interrogate results like these to discover the nuances of risk vs. benefit for vulnerable populations.
(Of course, unlike many other substances, cannabis prohibition has greatly complicated the process of discovering what exactly those relative benefits and risks are. But perhaps that’s another article for another day.
If you or someone you know is in crisis and needs immediate help, call the National Suicide Prevention Lifeline at 1-800-273-TALK (8255).