Early signs of cognitive decline may be reflected in driving habits

Early indications of cognitive decline could show up in the way we drive, meaning that decisions about when we travel and which routes we take may offer clues about future brain health.

Researchers at Washington University in St Louis report that people who start driving less frequently and who increasingly rely on familiar roads may be signalling a need for earlier support, particularly for drivers who could be at risk of a future crash.

Driving behaviour data as an early signal of cognitive decline

Alongside other symptoms, details of a patient’s driving may contribute to assessment. The researchers demonstrated that combining GPS-tracker information with standard age and memory tests, plus other demographic measures, allowed them to correctly detect cognitive decline in people with pre-existing mild cognitive impairment (MCI) 87 percent of the time.

"Early identification of older drivers who are at risk for accidents is a public health priority, but identifying people who are unsafe is challenging and time-consuming," says neurology researcher Ganesh Babulal.

"We found that using a GPS data tracking device, we could more accurately determine who had developed cognitive issues than looking at just factors such as age, cognitive test scores, and whether they had a genetic risk factor related to Alzheimer's disease."

Study participants and how driving patterns were tracked

The team examined data from 56 people already diagnosed with MCI (considered a precursor to Alzheimer’s disease) and compared them with 242 individuals of a similar demographic who had no cognitive problems. Across all participants, the mean age was 75.

Driving habits were captured automatically from the volunteers’ vehicles over as long as 40 months. These records were assessed alongside results from widely used tests, including measures of memory, attention, and executive function.

What changed for participants with mild cognitive impairment (MCI)

After accounting for factors such as age, education, and genetic risk for Alzheimer’s, those with MCI showed clear shifts in driving over time: they got behind the wheel less often, travelled to fewer destinations, took less complex routes, and were less likely to speed.

When the driving information was assessed on its own, it correctly identified people with MCI 82 percent of the time. The researchers note that some of this may reflect the self-regulation that often occurs with ageing, but they say it could also serve as an early indicator of cognitive decline.

"Looking at people's daily driving behavior is a relatively low-burden, unobtrusive way to monitor people's cognitive skills and ability to function," says Babulal.

Although it can feel easy to drive on autopilot-particularly after years on the road-driving actually demands considerable mental processing and coordination, which helps explain why distractions can be so hazardous.

What the researchers want to test next

Next, the team intends to evaluate the idea in larger and more diverse populations. They also plan to incorporate additional variables that could affect driving, including the type of vehicle, the geographical area, and other health conditions.

"This could help identify drivers who are at risk earlier for early intervention, before they have a crash or near-miss, which is often what happens now," says Babulal.

"Of course, we also need to respect people's autonomy, privacy, and informed decision-making and ensure ethical standards are met."

The research has been published in Neurology.