‘It is a public health threat just like alcohol’: Marijuana dependence linked to higher risk of suicide

New York: Hospital and emergency room patients diagnosed with cannabis use disorder – defined as an inability to stop using cannabis even when the drug is causing harm – died at almost three times the rate of individuals without the disorder over the next five years, according to a study published on Friday (AEDT), the largest on the subject.

Patients with cannabis use disorder were 10 times as likely to die by suicide as those in the general population. They were also more likely to die from trauma, drug poisoning and lung cancer. Those numbers suggested the disorder was about half as dangerous as opioid addiction and slightly less dangerous than an alcohol use disorder, the researchers said.

Recent research suggests that three in 10 cannabis users will develop cannabis use disorder.Credit: AP

A second report, published earlier in the week, found more cases of schizophrenia and psychosis in Canada had been linked to cannabis use disorder since the drug was legalised.

“Many people think, ‘Oh, cannabis is not harmful – it’s organic, it’s natural; how great’,” said Dr Laura Bierut, a psychiatrist at Washington University School of Medicine in St Louis who is an author of an editorial accompanying the study of death risk. But the marijuana sold today was far more potent and more harmful than what baby boomers smoked in the 1960s and 1970s, she said.

“It is a public health threat just like alcohol,” Bierut said.

Recent research suggests three in 10 cannabis users will develop the disorder, defined as being unable to stop using cannabis even though it’s causing serious health and social problems. As with alcohol, many people use marijuana recreationally without adverse effects or addiction.

The researchers took advantage of records in Ontario, Canada that capture millions of residents’ encounters with the government health system, which covers 97 per cent of the population there.

From the records, the scientists in Friday’s study identified 106,994 people who had been diagnosed with cannabis use disorder during an emergency department visit or a hospitalisation between 2006 and 2021.

The researchers linked the records with vital statistics records and found 3.5 per cent of the people died within five years of treatment for the disorder. In a matched comparison group of people of the same age and sex, the death rate was 0.6 per cent.

The authors then made adjustments to account for other risk factors that may have contributed to their deaths, including mental health disorders, other substance use and conditions such as heart disease and cancer.

Even when taking deaths by those other causes out of the equation, the researchers concluded that patients with cannabis use disorder were at a 2.8-fold increased risk of death compared with the general population. The risk was greatest in adults ages 25 to 44.

Dr Daniel Myran, an assistant professor of family medicine at the University of Ottawa and the study’s first author, said these were most likely underestimates of cannabis’s toll.

This article originally appeared in The New York Times.

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