Subtle changes in older adults' driving habits may offer early clues about brain health and dementia risk, according to research to be presented at the American Stroke Association's International Stroke Conference 2026. The study of 220 adults aged 65 and older found that 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.
Researchers tracked participants' driving behavior using car sensors for over five years, monitoring metrics like speeding, collisions, hard braking, and hard cornering. Brain imaging conducted within the study's first year measured white matter hyperintensities—areas of damage caused by reduced blood flow to brain tissue. During follow-up, 17% of participants developed cognitive impairment, with most later 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," said study author Chia-Ling Phuah, M.D., M.M.Sc. White matter damage in the back of the brain, which processes visual information and coordinates movement, showed the strongest connection to unsafe driving and crashes.
Notably, participants taking blood pressure medications—particularly angiotensin-converting enzyme (ACE) inhibitors—were less likely to exhibit risky driving behaviors even when brain scans revealed white matter damage. "This suggests that these medications may help support brain health as we age," Phuah noted. According to the American Heart Association's 2025 High Blood Pressure Guideline, early treatment is recommended to maintain brain health and cognition.
The findings have significant implications for identifying older adults at higher risk for unsafe driving and cognitive problems. Monitoring driving behavior with commercial in-vehicle data loggers could help detect subtle changes before traditional memory symptoms appear. "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," said Nada El Husseini, M.D., M.H.Sc., FAHA, chair of the American Heart Association's 2023 scientific statement on cognitive impairment after stroke.
Study limitations include a small sample size, with most participants being white and college-educated, potentially limiting generalizability to more diverse populations. Medication use was self-reported, which could introduce errors. The research team plans larger studies with more diverse participants to confirm and extend these findings. The study was part of the Driving Real-World In-Vehicle Evaluation System project based at Washington University in St. Louis.
With approximately 6.9 million U.S. adults aged 65 and older living with Alzheimer's disease in 2024, according to American Heart Association statistics, identifying early warning signs of cognitive decline is increasingly important. The research suggests that everyday driving patterns could serve as a practical, non-invasive indicator of brain health changes, potentially allowing for earlier interventions and support for maintaining independence and safety.
