A recent study from the University of Michigan indicates that efforts to prevent cannabis-impaired driving should also target older adults, not just younger populations. The research, led by addiction psychologist Erin E. Bonar, Ph.D., found that 20% of people over age 50 who use cannabis reported driving within two hours of using the drug at least once in the past year.
This behavior raises concerns about impaired reaction times and attention while driving. The study was published in Drug and Alcohol Dependence and used data from the National Poll on Healthy Aging, which is based at the U-M Institute for Healthcare Policy and Innovation.
The research revealed that adults aged 50 and over who use cannabis daily or nearly daily were three times more likely to drive soon after using compared to those who rarely use it. Those using cannabis for mental health reasons were twice as likely to report post-use driving as those who did not cite mental health as a reason. Additionally, men over 50 who use cannabis were 72% more likely than women in the same age group to drive after using THC-containing products.
Among respondents aged 50 and up, 21% reported using a cannabis product at least once in the last year. Of these users, 27% said they used it daily or almost daily, while 43% had used it only once or twice; others reported monthly (14%) or weekly (16%) use.
Bonar noted that while certain groups could benefit from targeted messaging about driving risks after cannabis use, broad-based prevention messages are needed. “Helping adults over 50 who choose to use cannabis understand the potential impacts of today's more potent cannabis, compared with the forms available in their younger years, is also important,” Bonar said.
The study found no significant differences in post-cannabis-use driving based on age group within those over 50, race, ethnicity, income level, loneliness history, caregiver status, or whether recreational cannabis was legal in their state.
When asked about reasons for using cannabis, 52% cited mental health or mood-related motives and 67% mentioned sleep-related motives. There was no difference in likelihood of post-use driving based on pain management or other medical reasons; however, there was some indication that those using it for sleep might be more likely to drive afterward.
Bonar emphasized the importance of educating older adults about evidence-based treatments for conditions like sleep issues and mental health concerns: “This suggests a need to help adults age 50 and up understand that there are options for treating these conditions that have much more evidence behind them than cannabis.”
She also highlighted the need for guidelines considering both aging’s effects on cognitive abilities and possible interactions between cannabis and prescription medications common among older adults.
Health care providers and public health agencies may want to encourage strategies such as consuming cannabis before bedtime—when driving is less likely—or planning ahead with designated drivers or ride-sharing services.
Bonar holds affiliations with several university centers including IHPI, U-M Addiction Center, U-M Injury Prevention Center, and U-M Eisenberg Family Depression Center. Additional authors on this study include Lianlian Lei, Matthias Kirch, Kristen P. Hassett, Erica Solway, Dianne C. Singer, Sydney N. Strunk, J. Scott Roberts, Preeti N. Malani, and Jeffrey T. Kullgren.
Further information can be found in a recent National Poll on Healthy Aging report regarding driving behaviors among people age 65 and over at https://michmed.org/w4Ayn.
