Subtle changes in everyday driving behaviour could serve as an early red flag for cognitive decline and dementia, according to a significant new scientific study. Researchers have identified specific, measurable alterations in driving patterns that are strongly associated with mild cognitive impairment (MCI), a potential precursor to conditions like Alzheimer's disease.
Tracking Driving Patterns Over 40 Months
The research, published in the respected journal Neurology, involved 298 participants all aged 65 or older. Each volunteer underwent an initial cognitive assessment and was then followed for a period of 40 months, with annual check-ups. At the study's outset, 56 individuals were diagnosed with MCI, while 242 were classified as having normal cognition.
To gather objective data, scientists fitted the participants' cars with GPS-enabled tracking devices. These dataloggers meticulously recorded a range of variables, including the number of journeys taken, the time of day and distance travelled, destinations, and the frequency of events like speeding, hard braking, and aggressive cornering.
Key Changes in Driving Behaviour
The analysis revealed clear and consistent differences between the two groups. Older adults with MCI made fewer trips overall, particularly avoiding driving after dark. They were also less inclined to embark on long-distance journeys and tended to stick rigidly to familiar routes, shunning new or unpredictable environments.
Interestingly, while those with MCI were less likely to speed, they demonstrated a significant increase in the frequency of taking turns too fast (hard cornering) over the follow-up period. Researchers suggest that some behaviours, like avoiding long trips, may be conscious or subconscious adaptive strategies to cope with declining skills. In contrast, the rise in hard cornering likely points directly to a deterioration in driving performance itself.
A Powerful Predictive Tool
Perhaps the most striking finding was the predictive power of this driving data. The research team developed a model that could predict a participant's cognitive status based solely on their driving patterns. This model proved more accurate at distinguishing between people with and without MCI than models based on traditional cognitive test scores, age, sex, race, education, or even genetic predisposition.
The study authors concluded that "digital driving biomarkers hold promise for early identification of cognitive impairment" and could complement existing methods for assessing an older person's fitness to drive. They call for future research to track how these metrics change as individuals progress from normal cognition to MCI and dementia.
Broader Context and Expert Commentary
This study aligns with existing expert knowledge. The Alzheimer's Association notes that dementia can affect the complex skills needed for safe driving, including spatial awareness, judging distances, and processing visual information like colour and contrast. Nearly one million people in the UK are estimated to be living with dementia, and the Alzheimer's Society states that one in three of those with the condition still drives.
However, the charity emphasises that "everyone with dementia will eventually be unable to drive safely", with most needing to stop during the middle stages of Alzheimer's disease. The new research offers a potential pathway for earlier, more objective discussions about driving safety, allowing for timely support and planning.
The authors advocate for collaboration between clinicians, researchers, and policymakers to integrate such digital monitoring ethically, upholding standards for privacy, autonomy, and informed decision-making.
