Medical Marijuana Use Tied to Vaping Marijuana

By Lisa Rapaport

August 31, 2020

(Reuters Health) - Adults who use marijuana for medical purposes are more likely to vape the drug than people who use it for other reasons, a U.S. study suggests.

Researchers examined data from the 2017 and 2018 Behavioral Risk Factor Surveillance System on 8,255 people who reported recently using marijuana. Overall, the majority of participants smoked marijuana (77.2%), while only a minority vaped (10.5%) or ingested it as a food or drink (8.1%).

However, among people who used marijuana for medical purposes, 71.5% reported vaping it, whereas 55.2% smoked it and 60.3% consumed an edible form.

"There may be variable health risks depending on how people use marijuana, and this is a much-needed area of research and investigation," said lead author Dr. Stephen Baldassarri of Yale University School of Medicine in New Haven, Connecticut.

"It is certainly a good idea for clinicians to routinely screen patients for drug use and to ask specifically about marijuana smoking and vaping, especially in people who are already smoking cigarettes or vaping nicotine," Dr. Baldassarri said by email.

The U.S. Centers for Disease Control and Prevention had received a total of 2,807 reported cases of lung injuries associated with vaping marijuana as of February 2020, Baldassarri and colleagues note in the American Journal of Preventive Medicine. Most cases were tied to vaping the main psychoactive component in marijuana, tetrahydrocannabinol, the study team notes.

In the current analysis, vaping of marijuana also varied by state.

For example, marijuana vaping was most common (15%) in Florida, one of two states where smoking marijuana wasn't legal, followed by California (13%), where recreational marijuana was legal, and Idaho (12%), where marijuana wasn't legalized for medicinal or recreational purposes.

Vaping marijuana was also more common among white people (70.4%), than other racial or ethnic groups in the study.

Attending college was also associated with higher rates of vaping marijuana (76.4%), as was e-cigarette use for nicotine products (23.3%).

One limitation of the study is the potential for self-reported data to be subject to reporting bias, especially when marijuana users resided in states where it wasn't legal or wasn't allowed for the reasons they used the drug. Another limitation is that survey respondents could only report their primary mode of marijuana use.

Even so, the results highlight the importance of screening for marijuana use in routine checkups and advising patients on the health risks associated with certain delivery modes, such as vaping, said

"Cannabis use is widespread in the U.S. and rarely addressed in routine healthcare," said Erin Bonar, a licensed clinical psychologist at the University of Michigan Addiction Center & Michigan Medicine in Ann Arbor who wasn't involved in the study.

"As part of a holistic understanding of a patient's health, clinicians should screen for cannabis use and help patients address any underlying health concerns, possible misuse or cannabis use disorder, and/or use of products that may be especially damaging, such as vapes that contain vitamin E acetate," Bonar said by email.

SOURCE: American Journal of Preventive Medicine, online July 16, 2020.