Medical Marijuana? Cancer Patients Use Less Cannabis Than General Public

According to data collected from 19,055 participants between 2013 and 2018, cancer patients across the country reported significantly less marijuana use than people who never had cancer, even after correcting for age, race, gender, and other factors. Photo credit: VCU Massey Cancer Center

The study shows that between 2013 and 2018, when many states legalized marijuana for recreational use, cancer patients continued to abstain from it in large numbers.

Last month, three states – Virginia, South Dakota, and Connecticut – joined more than a dozen others that legalized marijuana – also known as cannabis – for recreational use. Despite these changing laws and growing social acceptance of the drug, however, a new study finds that use among cancer patients is still lower.

The study published today (August 13, 2021) in the journal cancer by researchers at Virginia Commonwealth University’s Massey Cancer Center, analyzed data from nearly 20,000 people over a four-year period and found that reports of marijuana use in cancer patients peaked at 9%, compared with 14% in humans without a history of cancer.

“Even if we looked at whether someone had used cannabis in the four years of observation and we control factors such as age and race, cancer patients still did not increase their use over time like the general population,” said the study’s lead author, Bernard Fuemmeler, Ph. .D., MPH, assistant director of population science and interim co-director of the cancer prevention and control research program at the VCU Massey Cancer Center. “I would have expected that they would at least reflect what is happening in the general population.”

This paper was based on data collected between 2013 and 2018 from the Population Assessment of Tobacco and Health (PATH), which tracks a representative sample of Americans to study smoking behavior, including tobacco and marijuana.

In people who have never had cancer, rates of marijuana use increased during the four-year PATH study. During the same period, there was a surge in recreational marijuana legalization across the country.

“As law enforcement agencies change, we expect attitudes and perceived benefits and harms to change,” said Sunny Jung Kim, Ph.D., study co-author, Harrison Scholar at VCU Massey Cancer Center, and assistant professor of health behavior and policy . at the VCU School of Medicine. “This work gives us a perspective on the prevalence of cannabis use in cancer patients and how it has changed over time.”

But why don’t cancer patients follow the same trend as the rest of the population? The likelihood that a cancer patient would have used marijuana in the past year was essentially unchanged between 2013 and 2018.

“There’s that element of a life-changing moment when you have cancer,” said Fuemmeler, who is also a professor of health behavior and policy at the VCU School of Medicine and who holds the Gordon D. Ginder, MD, Chair in Cancer Research at Massey. “You have to take care of your health and think about whether something like cannabis is helpful or harmful.”

Regardless of cancer history, this latest analysis showed that people who reported greater pain were more likely to use marijuana, while women, the elderly, and those with higher incomes, health insurance, or better mental health.

The authors point out that more research needs to be done on the health effects of marijuana use on cancer patients and survivors so that doctors and patients can be better informed about whether the potential benefits may outweigh the risks.

“As with all health decisions, it is best to speak to your doctor before making any major changes,” said study co-author Egidio Del Fabbro, MD, Thomas Palliative Care Endowed Chair and Director of Palliative Care at VCU Massey Cancer Center and Professor of Internal Medicine at VCU. “Now that marijuana becomes legal in more parts of the country, we expect more questions and while we may not have all the answers, we are here to listen and provide the best evidence available to our patients.”

Reference: August 13, 2021, cancer.
DOI: 10.1002 / cncr.33794

Other authors on the study include Elizabeth Do, Ph.D. and Albert Ksinan, Ph.D., both from the VCU Department of Health Behavior & Policy.

This research was funded by Masseys NCI Cancer Center Support Grant P30 CA016059.