Medical cannabis use decreased in states where recreational use is legalized, study shows
Click Here to Manage Email Alerts
Key takeaways:
- Enrollment in medical cannabis programs rose by 33% from 2020 to 2022.
- However, enrollment decreased in 13 of 15 jurisdictions where nonmedical adult use was legal.
Enrollment in medical cannabis programs increased overall from 2020 to 2022, but it decreased in most states where nonmedical cannabis use became legal, research showed.
Medical cannabis use has risen significantly over the past decade, with the prevalence of U.S. citizens who use medical cannabis increasing from 1.2% in 2013 to 2014 to 2.5% in 2019 to 2020.
“We were interested in seeing how the national landscape has continued to change as more states legalize medical or adult-use cannabis, so we continued our data collection from state medical cannabis registries,” Kevin F. Boehnke, PhD, a research assistant professor at the University of Michigan, told Healio. “We also wanted to investigate how clinicians who authorize medical cannabis licenses fit into this national picture.”
In an ecological study published in the Annals of Internal Medicine, Boehnke and colleagues analyzed publicly available state medical cannabis registry data from 2020 to 2022.
They found that of the 39 U.S. jurisdictions that allowed medical cannabis use in 2022:
- 34 reported the number of patients;
- 29 reported data on authorizing clinicians; and
- 19 had data on patient-reported qualifying conditions.
Overall, the number of patients enrolled in medical cannabis programs increased by 33% during the study period, which Boehnke explained was unsurprising given that more states have allowed access to medical cannabis.
However, 13 of 15 jurisdictions had decreased enrollment after opening nonmedical adult-use dispensaries.
“We had previously seen decreases in patient enrollment after nonmedical adult use laws passed, but we were surprised at how dramatic some of the decreases were, especially in states like Arizona, where the patient population dropped by over 50% from 2021-2022,” Boehnke said.
He explained that several factors may have contributed to the decreases, “including no longer needing legal cover for use, the inconvenience of certification visits, licensing fees, or because people decide to purchase their cannabis products in the nonmedical adult-use market after these laws go into place.”
Additionally, the proportion of patient-reported qualifying conditions with substantial or conclusive evidence of therapeutic value decreased from 70.4% in 2020 to 53.8% in 2022.
Chronic pain was the common patient-reported qualifying condition in 2022 (48.8%), followed by anxiety (14.2%) and PTSD (13%).
In 2022, there were 29,500 clinicians who authorized medical cannabis, 53.5% of whom were physicians. The most common specialties these clinicians belonged to were:
- internal or family medicine (63.4%);
- physical medicine and rehabilitation (9.1%), and
- anesthesia or pain (7.9%).
Boehnke noted that primary care physicians “can advise patients that cannabis should only be purchased from certified dispensaries and should avoid purchasing from non-legal sources.”
“Furthermore, they should inform patients about potential harms of cannabis use (eg, overconsuming edibles, drugged driving, cannabis hyperemesis syndrome),” he said. “Finally, PCPs can offer compassionate care that frames cannabis like any other medication, offering advice on ways to maximize benefit and minimize harm.”
For future research, Boehnke advocated for continued efforts “to understand this changing landscape,” as well as “wider and uniform surveillance of attitudes and beliefs related to cannabis, cannabis use behaviors, and cannabis-related health effects.”
References:
- Boehnke K, et al. Ann Intern Med. 2024;doi:10.7326/M23-2811.
- Rhee TG, et al. Am J Prev Med. 2023;doi:10.1016/j.amepre.2023.03.005.