Driving Habits May Signal Onset of Dementia Years Before Diagnosis
New research reveals subtle changes in how older adults drive can be early indicators of cognitive decline, even before traditional symptoms appear.
- Changes in driving patterns—like reduced trips or sticking to familiar routes—may precede dementia diagnosis by years.
- Greater damage to the brain’s white matter is linked to increased driving errors and a higher risk of crashes.
- Blood pressure medication, particularly ACE inhibitors, appears to mitigate risky driving habits even with brain damage.
- Monitoring driving behavior could offer a non-invasive way to identify individuals at higher risk for cognitive decline.
St. Louis, Missouri – Subtle shifts in everyday driving habits could serve as an early warning system for dementia, according to a new study. Researchers found that changes behind the wheel can reveal tell-tale clues about brain health, potentially years before traditional memory and thinking symptoms emerge.
The research, which followed 220 motorists with an average age of 73 for five years, linked greater white matter damage in the brain to decreased driving, fewer trips, a tendency to take the same routes, and an increase in motoring errors. Interestingly, adults ages 65 and older taking blood pressure medication were less likely to exhibit these risky driving behaviors, even when brain scans showed damage.
Data collection spanned from 2016 to 2024, with participants undergoing continuous in-vehicle monitoring for metrics like trip frequency, distance, destination, speeding, collisions, hard braking, and hard cornering. Participants also received MRI brain scans at the beginning of the study, and nearly half had a second scan at least 12 months later, alongside annual clinical and cognitive assessments. Researchers analyzed the relationship between white matter damage and driving patterns.
“Driving habits in older adults can reveal early changes in brain health,” said Professor Chia-Ling Phuah, of the Barrow Neurological Institute in Phoenix. “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.”
The findings suggest that even small shifts in daily driving patterns can offer important clues about brain changes – sometimes before traditional memory and thinking symptoms are noticeable.
Drivers will change their behaviour in response to a decline in brain health
Among the 17% of participants who developed cognitive impairment, higher levels of white matter damage were associated with a greater likelihood of unsafe driving practices, such as hard braking, and more crashes. Specifically, damage to the back of the brain—responsible for processing visual information and movement—was linked to a higher risk of crashes.
However, participants taking medications to manage high blood pressure, especially ACE inhibitors, were less likely to exhibit risky driving, even with brain damage. Professor Phuah explained that the study’s findings suggest that monitoring driving behavior with in-vehicle data loggers could help identify older drivers at higher risk for unsafe driving, loss of independence, and subtle cognitive problems.
“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 added. “This effect was observed regardless of whether their blood pressure levels were at target levels. This suggests that these medications may help support brain health as we age.”
Anxiety at the wheel can be a red flag
Larry Duncan, a retired business owner from Pinehurst, North Carolina, experienced these changes firsthand. His wife, Pam, noted that while he was fine driving in familiar areas, he became anxious in new places requiring quick decisions, before his Alzheimer’s diagnosis in 2023. His doctor eventually advised him to stop driving, a difficult but necessary decision.
Pam, who now volunteers for the American Stroke Association, emphasized the importance of recognizing subtle changes. “In early-stage cognitive impairment, symptoms can be subtle, and driving is one of them. Don’t ignore these changes. As caregivers, our role is to support independence while having the courage to make tough decisions. You can live well with dementia, but it starts with awareness and action.”
The study findings are scheduled to be presented at the American Stroke Association’s International Stroke Conference in New Orleans next week. Duke University Neurology Professor Nada El Husseini, who was not involved in the study, praised the research.
“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,” El Husseini said. “The impact of ACE inhibitors on cognitive function and driving safety in people with white matter disease requires further investigation. Also, these results suggest cognitive screening and brain imaging might be considered for people with driving difficulties.”
There are signs you should never ignore
