Clear implications
Commenting on the findings for Medscape Medical News, Deepak D’Souza, MD, professor of psychiatry, Yale University, New Haven, Conn., said there is “concern about the unsubstantiated claims of cannabis having a beneficial effect in psychiatric disorders, the most common being depression.”
Dr. Deepak D'Souza
Dr. D’Souza, who was not involved with the study, called it “yet another piece of evidence suggesting that over the period of time during which cannabis laws have been liberalized, rates of past-month and daily cannabis use have increased, whereas rates of other substances, including alcohol, have remained stable.”
He suggested that a common limitation of epidemiological studies is that it is difficult to tell the direction of the association, “and it could be bidirectional.”
Nevertheless, there are clear implications for the practicing clinician, he added.
“If people have a history of depression, one should ask patients about the use of cannabis and also remind them about potential psychiatric negative effects of use,” Dr. D’Souza noted.
For the general public, “the point is that there is no good evidence to support cannabis use in depression treatment and, in fact, people with depression might be more likely to use it in problematic way,” he said.
Dr. Hasin agreed that it is “certainly possible that the relationship between cannabis use and depression is bidirectional, but the mechanism of this association requires more study.”
The study was supported by a grant from the National Institute on Drug Abuse to Dr. Hasin and by the New York State Psychiatric Institute. The study authors and Dr. D’Souza disclosed no relevant financial relationships.
This article first appeared on Medscape.com.