Cannabis use may be linked to increasing suicidal thoughts in young women, study finds

• A new study by the US National Institutes of Health has linked cannabis use and suicidality in young people.
• Young adults who used weed were more likely to consider suicide, but researchers don't know why.
• Women may be especially vulnerable to this increased risk of suicidality, the authors wrote.

A new study from the National Institutes of Health suggests there may be a link between cannabis use and rising rates of suicidal ideation, planning, and attempts among young people.

Both casual and habitual cannabis users were more likely to report suicidal thoughts and behaviors, according to an analysis of data from the 2008-2019 National Surveys on Drug Use and Health.

Any level of cannabis use seemed to correspond with an increase in suicidality, regardless of frequency of use or preexisting mental health conditions, the researchers wrote, though they said they weren't sure why.

Both cannabis use and mental health issues have grown more common in the US over the past decade. The number of American adults who report using cannabis has more than doubled between 2008 and 2019, according to the National Institute on Drug Abuse (NIDA). During that same period, rates of depression and suicidality also increased, especially among young people.

Nora Volkow, NIDA director and senior author of the study, told Insider that more research is needed to understand these findings. In the meantime, she said it's best to be prudent.

"We already know that marijuana can trigger psychotic episodes, and in people that are vulnerable, it can trigger schizophrenia," Volkow said. "So, when you have data like this, the message is that you should be cautious."

The study found higher risks for women using cannabis than men

The study, published Tuesday in JAMA Network Open, analyzed data from more than 280,000 Americans ages 18-35.

It supported past studies linking cannabis use and suicidality, and suggested that the association was stronger in women.

Women who used cannabis at any level were more likely to report suicidality compared to men with the same levels of cannabis use.

For instance, women who screened positive for both cannabis use disorder and a major depressive episode were twice as likely to report planning suicide compared to men in the same category.

Cannabis use disorder is defined as "a problematic pattern of cannabis use leading to clinically significant impairment or distress," according to the DSM-5, a manual known as the psychiatry "Bible."

As for those without a history of depression, nearly 14% of women with cannabis use disorders reported suicidal thoughts, compared to 3.5 percent of women who did not use cannabis. Among men, nearly 10% of those with CUD and 3% of those without it experienced suicidal ideation.

The researchers said they don't know which might come first: suicidal thoughts or cannabis use

There are a few different ways in which cannabis and mental health could interact.

Some people with preexisting mental health issues may self-medicate with cannabis to ease symptoms of depression, anxiety, or suicidal thoughts.

Peter Grinspoon, a primary care physician and cannabis specialist at Harvard Medical, told Insider that people who use cannabis for therapeutic purposes may also be at higher risk for suicide, but that correlation doesn't mean causation.

"I think the most straightforward explanation is that distressed people, who are more likely at risk for all types of negative outcomes including suicide, self-medicate with cannabis because it helps them relax, sleep, connect with others, and elevates their mood," Grinspoon told Insider. "I treat these people and it helps them."

Volkow said it's also possible that cannabis use could make the brain more reactive and vulnerable for suicidality. Cannabis acts on the endocannabinoid system, a collection of receptors which help regulate mood and buffer stress. Too much stimulation from cannabis could impact the body's own endocannabinoids, Volkow said.