Driving Habits May Signal Early Dementia – Study Finds

Subtle changes in driving habits may offer clues to the early stages of dementia – potentially years before a formal diagnosis.

A shrinking driving radius, fewer trips, and avoiding nighttime driving are common changes for many older drivers. However, a long-term study published by the American Academy of Neurology suggests these subtle shifts in daily life may be linked to early cognitive changes – even before a diagnosis of mild cognitive impairment (MCI). This research highlights the potential for using everyday activities to detect neurological changes.

Researchers tracked the driving behavior of older adults using GPS data loggers over time – in some cases for up to 40 months – and compared these patterns with annual memory and clinical assessments.

GPS Data Reveals Brain Changes

The research team, led by Ganesh M. Babulal from the Washington University School of Medicine in St. Louis, followed 298 older drivers for more than three years. Participants had an average age of 75, drove at least once a week, and were still actively driving at the start of the study. Fifty-six participants already had mild cognitive impairment, while 242 were considered cognitively healthy.

Each vehicle was equipped with a GPS data logger that automatically recorded every trip – from start to finish, including distance, duration, time of day, speed, braking behavior, and route deviations. Participants also underwent regular cognitive and memory tests. Genetic factors, such as the Alzheimer’s risk gene APOE ε4, were also recorded.

Driving Data Improves Predictive Accuracy for Dementia

Initially, driving patterns showed little difference between groups. However, over the years, participants with mild cognitive impairment drove less frequently, took shorter trips, and primarily stuck to familiar routes. They also increasingly avoided driving at night and rarely deviated from their usual routes.

Using this GPS data, researchers correctly predicted who would develop mild cognitive impairment in 82% of cases. When combined with age, test scores, and genetic markers, the accuracy increased to 87%. Without driving data, the accuracy rate was only 76%. “We were able to more accurately determine who developed cognitive problems using a GPS data-tracking device than with age, memory tests, or genetic factors alone,” explained Babulal.

Subtle Changes Behind the Wheel as Warning Signs

The study demonstrates that everyday behavioral changes while driving can serve as an early warning sign – often before memory problems become noticeable in daily life. Typical changes that researchers suggest paying attention to include:

• Fewer trips per month: approximately half a trip less per month on average.
• Decline in nighttime driving: a noticeable decrease compared to healthy drivers.
• Reduced route diversity: less frequent spontaneous detours or longer trips.

“Observing daily driving behavior is a relatively simple and unobtrusive way to assess cognitive function,” Babulal said. This could help identify at-risk drivers earlier, before accidents or near-misses become more common.

Ethical Considerations for Sensitive Driving Data

According to the researchers, early detection of at-risk drivers is also important from a public health perspective, as it can help provide timely support to maintain safety and mobility for as long as possible.

However, handling this data requires sensitivity. “We must respect people’s autonomy, privacy, and informed decision-making and ensure that ethical standards are met,” Babulal stated.

In brief:

• Driving behavior can reveal early signs of developing dementia – such as older adults driving less often, avoiding nighttime driving, or sticking to familiar routes.
• A U.S. study followed 298 drivers for over three years and was able to predict cognitive impairment with up to 87% accuracy using GPS data.
• These everyday signals can help detect memory problems early, before accidents occur – provided data privacy is protected.