Subtle changes in the way older adults drive, such as sticking to familiar routes and avoiding journeys after dark, could serve as an early warning sign of Alzheimer's disease, according to a new scientific study.
GPS Data Outperforms Traditional Memory Tests
Researchers from Washington University School of Medicine have discovered that analysing in-vehicle GPS data is a more effective method for identifying individuals at risk of cognitive decline than relying solely on age and standard memory tests. The study, published in the journal Neurology, followed 298 participants with an average age of 75 for just over three years.
The group included 56 people with mild cognitive impairment, a known precursor to Alzheimer's, and 242 who were cognitively healthy at the study's outset. All participants drove at least once weekly and had a data-tracking device installed in their cars.
Key Warning Signs in Driving Behaviour
While driving patterns were similar initially, clear differences emerged over time. The study found that older adults who developed mild cognitive impairment began to drive less overall each month, heavily favoured well-known routes, and significantly reduced their night-time driving.
By examining metrics like the average distance of trips, instances of speeding, and the variety of routes taken, researchers could predict with 82% accuracy whether a participant had developed mild cognitive impairment.
When this driving data was combined with factors like age, demographics, cognitive test scores, and genetic risk for Alzheimer's, the predictive accuracy improved to an impressive 87%. In contrast, using cognitive tests and genetic information alone achieved only 76% accuracy.
A Path to Safer Roads and Earlier Intervention
Lead study author Dr Ganesh Babulal emphasised the public health potential of this approach. "Early identification of older drivers who are at risk for accidents is a public health priority," he stated, noting that current methods are often challenging and time-consuming.
"Looking at people’s daily driving behaviour is a relatively low-burden, unobtrusive way to monitor people’s cognitive skills and ability to function," Dr Babulal explained. This method could flag at-risk drivers for support before a crash or near-miss occurs, which is often the current trigger for assessment.
The researchers also stressed the importance of balancing innovation with ethical considerations, including respect for personal autonomy, privacy, and informed decision-making. This passive monitoring via GPS offers a promising, real-world tool to help spot the earliest signs of brain changes, potentially allowing for earlier support and planning.
