That leaves methods that are invasive, like epidural, or expensive, like PET scans. These approaches cannot be used to screen large groups of people. “They’re not widely available,” said Mrs. Bayat. “They’re not very accessible or scalable.”
But a GPS device in someone’s car could monitor driving behavior almost continuously at low cost, using so-called digital biomarkers. “Studies have shown it directs changes in people with symptomatic Alzheimer’s,” said Ms. Bayat. “But some changes occur even earlier.”
The Washington University study included 64 older adults with preclinical Alzheimer’s as determined by epidural (the results were not shared with participants), and 75 who were considered cognitively normal.
For a year, researchers measured the driving performance of both groups – how often they accelerated or braked aggressively, exceeded or undershot the speed limit, made abrupt movements – and their “driving space” (number of trips, average distance, unique destinations, night trips) . “Only now, because we have these technologies, can we do this kind of research,” Ms Bayat said.
The study found that driving behavior and age could predict preclinical Alzheimer’s 88 percent of the time. Those findings could boost recruitment for clinical trials and enable interventions — such as a warning when a car is drifting — to keep drivers on the road. In areas with insufficient public transport (which most areas are), that could increase the independence of seniors.
dr. Jason Karlawish, a geriatrician and co-director of the Penn Memory Center, called the study “provocative” and well-designed. “The results suggest that monitoring cognitively intense behavior in the real world can detect the earliest, subtle signs of emerging cognitive impairment,” he said in an email.
Similarly, a study that analyzed medical records and consumer credit reports for more than 80,000 Medicare beneficiaries showed that seniors who were ultimately diagnosed with Alzheimer’s were significantly more likely to have delinquent credit card payments than those who were demographically similar but never received such diagnoses. They were also more likely to have subprime credit scores.