Cannabis use among older adults is increasing sharply in the United States. While the risks and benefits of cannabis use remain unclear, it is important to monitor risk factors for use, including low perception of harm. The objective of this study was to estimate recent national trends in perceived risk associated with cannabis use among older adults.
Trend analysis.
A total of 18,794 adults aged 65 and older participating in the 2015-2019 National Survey on Drug Use and Health, a cross-sectional nationally representative survey of non-institutionalized individuals in the United States.
We estimated the prevalence of older adults who believe that people who smoke cannabis once or twice a week are at great risk of harming themselves physically and in other ways. This was examined across cohort years and stratified by demographic characteristics, diagnosis of chronic disease, past-month tobacco and binge alcohol use, and all-cause emergency department use.
Between 2015 and 2019, perceived risk associated with regular use decreased from 52.6% to 42.7%, an 18.8% relative decrease (p < 0.001). Decreases in perceived risk were detected in particular among those never married (a 32.6% relative decrease), those who binge drink (a 31.3% relative decrease), use tobacco (a 26.8% relative decrease), have kidney disease (a 32.1% relative decrease), asthma (a 31.7% relative decrease), heart disease (a 16.5% relative decrease), chronic obstructive pulmonary disease (a 21.5% relative decrease), two or more chronic conditions (a 20.2% relative decrease), and among those reporting past-year emergency department use (a 21.0% relative decrease) (ps < 0.05).
The perceived risk of regular cannabis use is decreasing among older adults. We detected sharp decreases in risk perception among those with chronic disease and high-risk behaviors, including tobacco and binge alcohol use. As the number of older adults who use cannabis increases, efforts are needed to raise awareness of the possible adverse effects with special emphasis on vulnerable groups.

© 2021 The American Geriatrics Society.