A preliminary study to be presented at the American Stroke Association's International Stroke Conference 2026 suggests that monitoring older adults' driving habits could provide early warning signs of cognitive decline and dementia. The research, which tracked 220 adults aged 65 and older over five years, found that greater white matter damage in the brain was associated with decreased driving, fewer trips, repetitive routes, and more driving errors, particularly in those who later developed dementia.
"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., associate professor of neurocritical care and co-director of the Neuro Analytics Center at Barrow Neurological Institute in Phoenix.
Researchers used car sensors to track driving behavior—including speeding, collisions, hard braking, and hard cornering—for more than five years. Participants also underwent brain imaging to measure white matter hyperintensities, areas of damage caused by reduced blood flow to brain tissue. Over the study period, 17% of participants developed cognitive impairment, most diagnosed with Alzheimer's disease.
Among those who developed cognitive impairment, higher white matter hyperintensity burden was linked to unsafe driving practices and more crashes. Notably, damage in the back part of the brain, which processes visual information and coordinates movement, was most strongly tied to unsafe driving and crashes, pointing to a potential early warning marker for higher driving risk in older adults.
In contrast, participants taking blood pressure medications, particularly angiotensin-converting enzyme (ACE) inhibitors, were less likely to exhibit risky driving behaviors even when brain damage was present. "This effect was observed regardless of whether their blood pressure levels were at target levels," Phuah said. "This suggests that these medications may help support brain health as we age."
According to the American Heart Association 2026 Heart and Stroke Statistics, about 6.9 million (10.9%) adults 65 years or older in the United States were living with Alzheimer's disease in 2024. The study's findings suggest that monitoring driving behavior with commercial in-vehicle data loggers may help identify older adults at higher risk for unsafe driving, loss of independence, and subtle cognitive problems.
Nada El Husseini, M.D., M.H.Sc., FAHA, chair of the American Heart Association's 2023 scientific statement Cognitive Impairment After Ischemic and Hemorrhagic Stroke, said, "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."
Key limitations include a small study size and a predominantly white, college-educated participant pool, so results may not generalize to more diverse populations. Medication use was self-reported, which could introduce errors. The next step will be larger studies with more diverse participants to confirm these findings.
The study was part of the Driving Real-World In-Vehicle Evaluation System (DRIVES) project based at Washington University in St. Louis, with data collected from 2016 to 2024.
