Study: Growing Prevalence of Alzheimer's Suggests Need for Frequent Driving Tests

Older people may need to have their driving skills checked once in a while given the growing prevalance of Alzheimer's disease and other dementias, according to a study reported in the October issue of the Journal of the American Geriatrics Society.

The study, which was the first to track driving performance over time in older adults, found that it not only declined in individuals in the early stages of Alzheimer's disease, but also in individuals who did not have any form of dementia. However, the researchers noted that people with dementia, generally in the mild stages, suffered a faster decline than nondemented individuals.

"This is a preliminary study, but it suggests that testing individuals with mild dementia every six months can be useful to identify those who become unsafe," said study author Janet M. Duchek, associate professor of psychology and of occupational therapy at the university.

"Appropriate testing is important," said researcher Dr. John C. Morris of the university's Alzheimer's Disease Research Center. "For individuals who still drive safely, it can be reassuring and help them remain independent. It also can be used to follow individuals to detect the development of unsafe driving behaviors and intervene, hopefully before there is an actual crash or other problem."

The researchers administered a road test every six months to individuals and compared the time it took each group to go from a passing to a failing grade. The group with mild Alzheimer's disease declined the fastest, followed by the very mild dementia group.

Performance in the non-dementia group also declined over time, though at a slower rate than the other two groups. When data from all three groups was combined, increased age alone appeared to be a risk factor in driving performance.

"While the majority of the nondemented people we tested remained very safe drivers, as we followed them, more and more became unsafe," Morris says. "Age-related changes other than dementia likely contribute to driving performance and should be further investigated in larger groups of older adults."

Duchek and Morris emphasize the need to educate physicians and families about the importance of detecting changes that may impair an individual's driving performance. Red flags include an inability to maintain speed or to stay in one lane while driving, hesitating at turns or becoming lost, particularly in familiar areas.

"One of the features of dementia is that individuals lose insight and may not recognize that they are becoming unsafe," Morris said. "We must increase public awareness about driving issues in demented persons and empower families and health care professionals to intervene before a tragedy occurs."

Other sources: Journal of the American Geriatrics Society, vol 51, pp. 1342-1347, October 2003