Cannabis Use in Older Adults Continues Upward Trend

Methods and Results

The letter's authors reviewed data for nearly 15,000 older adults from the National Survey on Drug Use and Health from 2015 through 2018. Cannabis use was identified by asking participants whether they had smoked or ingested "marijuana," "hashish," "pot," "grass" or "hash oil" in the past year, and the authors calculated both absolute and relative changes in prevalence during the study period.

Overall, the authors reported that estimated prevalence of cannabis use during the previous year increased from 2.4% in 2015 to 4.2% in 2018. Although men were more likely than women to report using cannabis, women had significantly higher relative increases from year to year.

Regarding specific subgroups, the authors identified a relative increase in cannabis use of nearly 114% among older adults with a college degree or higher from 2015 to 2018, and a relative increase of more than 129% in households making more than $75,000 per year. In contrast, relative use increased just 17.4% in older adults with a high school education or less and just 16.2% in households with incomes of less than $20,000.

In terms of chronic disease, the authors detected a 180% relative increase in cannabis use among older adults with diabetes over the study period, and a 109% increase in those with heart disease. Smaller relative increases were seen in older adults with hypertension (71%) or cancer (33%) and in those with fewer than two chronic diseases (96%).

The largest absolute change in cannabis use occurred in older adults who had received treatment for mental health in the previous year. In 2015, the prevalence of cannabis use in this group was 2.8%; by 2018, prevalence had more than doubled to 7.2%.

Finally, the research showed increased use of cannabis in older adults who had also used substances such as alcohol and tobacco in the previous year. In those groups, relative cannabis use increased by 117.2% and 72.9%, respectively.

Important Points for FPs

As for the absolute number of individuals affected, applying 2018's estimated 4.2% prevalence of past-year cannabis use to the more than 52 million people 65 and older who live in the United States yields a total of almost 2.2 million older adults.

And according to Joseph Palamar, Ph.D., M.P.H., an associate professor in the Department of Population Health at NYU Langone and the study's senior author, the actual number may be higher.

The original survey "did not ask about vaping of marijuana or THC products, so it's possible use was underestimated," Palamar said in the press release. "We must follow vaping trends closely among all age groups."

For family physicians, the findings mean that about one in every 25 older patients may be using cannabis. And because cannabis produces its own health effects and may interfere with the effectiveness of certain drugs, FPs need to know if their patients are using cannabis to educate them on the risks and benefits of its use and avoid potentially dangerous drug interactions.

To Han, meanwhile, the findings give health care professionals an opportunity to discuss cannabis use with their patients.

"As more older adults use cannabis, whether for therapeutic or recreational purposes, it is important for health care providers to counsel their patients -- despite the very limited evidence base -- on the benefits and harms of cannabis use among older adults," Han said.

Although the AAFP officially opposes the recreational use of marijuana, it also supports decriminalization of marijuana possession for personal use and advocates that further research be conducted on the safety and health effects of recreational marijuana use.

Members are also invited to review the Academy's position paper on marijuana and cannabinoids, which acknowledges that cannabis products may have potential therapeutic benefits but cautions that they also may negatively affect personal health.