Ohio State research suggests marijuana users with mental health issues more likely to

Researchers at the Wexner Medical Center at Ohio State collaborated with the College of Medicine in a study that found young people with mood disorders who use marijuana are at a higher risk for death and self-harm. Credit: Mackenzie Shanklin | Photo Editor

Young people with mood disorders may want to think twice before using marijuana, Ohio State researchers suggest.

Researchers at the Wexner Medical Center at Ohio State and the College of Medicine found marijuana users between the ages of 10-24 with mood disorders — including major depression, bipolar disorder and persistent depressive disorder — are at a higher risk for self-harm and death by all causes, Cynthia Fontanella, lead author of the study and associate professor of psychiatry and behavioral health, said. 

The study, published Jan. 19 in the journal JAMA Pediatrics, looked at Ohio Medicaid claims and death certificate data from 204,000 people aged 10-24 diagnosed with a mood disorder between July 2010 and December 2017, Fontanella said. Researchers looked for diagnosed cannabis use disorder as well as non-fatal self-harm and deaths by suicide, unintentional overdose, motor vehicle accidents and homicide.

Cannabis use disorder is a subsection of substance use disorder. According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), cannabis use disorder requires the presence of several symptoms associated with drug use, including overconsumption, one or more failed attempts at reducing cannabis use and continued use despite negative impacts on work, school or relationships.

More than 10 percent of people studied used cannabis. Cannabis users in the study were three times more likely to self-harm, Fontanella said. They were about 60 percent more likely to die by unintentional overdose and three times more likely to die by homicide — although the reasons for such are unclear. 

One in four people aged 10-24 likely have a mood disorder, Mary Fristad, a professor emeritus in the Department of Psychiatry and Behavioral Health and director of academic affairs and research development at Nationwide Children’s Hospital Big Lots Behavioral Health Services, said, although numbers have gone up during the pandemic.

“People don’t keep the same sleep and wake cycles; they are out of rhythm with when they eat, what they do,” Fristad said. “And that’s very disruptive to mental health as well as physical health.”

Although the researchers couldn’t pinpoint specific causes for the link between marijuana use and death in those with mood disorders, Fristad said young people may seek marijuana’s relaxing, euphoric effects as a coping mechanism for their depression.

Fontanella said an increased chance of risky and dangerous behavior linked with cannabis use may contribute to higher rates of death by homicide.

Marijuana use in the study was correlated with several demographics, including being 19 years old or older, male, Black, having bipolar disorder, having a history of self-harm and prior hospitalizations, Fontanella said. She said risk factors for marijuana use among young people with mood disorders can be addressed by physicians to reduce negative outcomes.

“Clinicians need to be aware of the negative health outcomes associated with cannabis use disorder and they need to screen for cannabis use disorders,” Fontanella said. “Clinicians should have an open discussion with youths and parents about cannabis use.”

People under the age of 25 process marijuana differently due to continued growth and development, Fristad said.

“It’s not just a bunch of older people telling younger people, ‘Do as I say, not as I do,’ but it’s, ‘My brain works differently than your brain; I want to protect your brain,’” Fristad said.