A preliminary study suggests that subtle changes in older adults' driving habits may offer early clues about brain health and cognitive decline. The research, to be presented at the American Stroke Association's International Stroke Conference 2026 in New Orleans, found that greater white matter damage in the brain was associated with decreased driving, fewer trips, repetitive routes, and more driving errors, particularly among participants who later developed dementia.
Researchers from Washington University in St. Louis analyzed driving data from 220 adults aged 65 and older over more than five years using in-vehicle sensors. Participants also underwent brain MRI scans to measure white matter hyperintensities—areas of damage caused by reduced blood flow. The study found that those with more white matter damage tended to drive less and showed sharper declines in route variability. Over the follow-up period, 17% of participants developed cognitive impairment, most diagnosed with Alzheimer's disease.
“Driving habits in older adults can reveal early changes in brain health. How often people drive, where they go, and how much they vary their routes may signal underlying damage to the brain’s white matter, which is linked to cognitive decline and dementia,” said study author Chia-Ling Phuah, M.D., M.M.Sc., an associate professor of neurocritical care and co-director of the Neuro Analytics Center at Barrow Neurological Institute in Phoenix.
White matter damage in the back of the brain—responsible for processing visual information and coordinating movement—was most strongly tied to unsafe driving and crashes. Notably, participants taking blood pressure medications, particularly ACE inhibitors, were less likely to exhibit risky driving behaviors even when brain damage was present. This effect was observed regardless of whether blood pressure levels were at target.
“One especially promising finding was that people taking blood pressure medications, particularly ACE inhibitors, tended to maintain safer driving habits even when their brain scans revealed more damage,” Phuah said. “This suggests that these medications may help support brain health as we age.”
Nada El Husseini, M.D., M.H.Sc., FAHA, chair of the American Heart Association’s 2023 scientific statement on cognitive impairment after stroke, noted, “What’s surprising about these findings is that people taking ACE inhibitors were less likely to have impairment in their driving despite the extent of white matter disease. The impact of ACE inhibitors on cognitive function and driving safety in people with white matter disease requires further investigation.”
The study's limitations include a small sample size, predominantly white and college-educated participants, and self-reported medication use. Larger, more diverse studies are needed to confirm the findings. The American Heart Association's 2026 Heart and Stroke Statistics indicate that about 6.9 million U.S. adults aged 65 and older were living with Alzheimer's disease in 2024.
For more information on brain health, visit the American Heart Association's Brain Health page. The full abstract is available in the International Stroke Conference 2026 Online Program Planner.
