A new study finds that
use in the United States more than doubled over a seven-year period and attributes most of the growth to efforts to legalize the medicinal use of cannabis at the state level. was conducted through an analysis of data from the National Survey on Drug Use and Health, which has been conducted annually since 1971. In 2013, a new question was added to the survey asking respondents if any cannabis use in the previous 12 months had been recommended by a doctor. The first year the question was asked, 1.2% said their cannabis use had been recommended by their physician. Only seven years later, the figure had jumped to 2.5%, according to data from the national surveys conducted between 2013 and 2020.The authors of the study, Greg Rhee and Robert Rosenheck, both affiliated with the Yale School of Medicine’s psychiatry department and the U.S. Department of
(VA) New England Mental Illness, Research, Education and Clinical Center, note that cannabis has been legalized in 39 U.S. states and Washington, D.C. Using data from the national survey, they determined that the use of medical marijuana increased an average of 12.9% per year over the seven-year study period.“This study documents a continued nationwide increase in use of cannabis for diverse medical purposes between 2013 and 2020,” the authors of the paper wrote. “Living in a state that legalized medical cannabis remained significantly associated with greater odds of medical cannabis use.”
Study Cites Factors Associated With Medical Cannabis Use
The study revealed several factors associated with an increase in medical marijuana use, such as being aged 18 to 25 years old, being male and having never been married. Other variables that showed a significant association with medical marijuana use include having completed a college degree and not having health insurance. The authors noted that such associations, however, do not mean that those groups were more likely to use medical marijuana or that they saw greater increases in the prevalence of cannabis during the study period.
The authors write that the study does not attempt to determine how transitioning from laws legalizing only medical marijuana to the legalization of recreational marijuana affected the prevalence of medical cannabis use.
“Unfortunately, it’s outside the scope of analysis because we were not able to distinguish states by legalization status,” Rhee explained in an email to Marijuana Moment.
The study also analyzed medical marijuana use by respondents who specified a medical condition and revealed some associations among those groups.
“Clinically relevant subgroups that experienced significantly greater odds of medical cannabis use included: poorer self-rated health statuses, past-year major depressive episode, cocaine use disorder, and use of non-prescription pain relievers,” the study reads.
The authors of the study wrote that “the association of medical cannabis use with depression, cocaine use disorder, and non-medical use of pain relievers suggests it may have either been prescribed for those conditions or used on patient initiative for these problems,” although they acknowledged that the national survey data does not provide enough information to draw those conclusions.
The prevalence of medical marijuana use increased over the study period, the authors note, despite conclusive health data on the risks and benefits of using cannabis.
“Medical cannabis is increasingly used,” Rhee said. “But, long-term medical benefits and harms are not clearly known for multiple medical conditions. Future studies are needed to weigh between effectiveness and safety of medical cannabis.”
The study also notes that cannabis “does not generally lead to overdose deaths (in contrast to opioids)” although “several unintended consequences (e.g., developing psychosis and motor vehicle crashes) have been documented.”
The study, “Increasing Use of Cannabis for Medical Purposes among US Residents, 2013-2020,” was published earlier this month as a pre-proof for the American Journal of Preventive Medicine.