Mild Alzheimer's Patients Can Drive Safely
Jan. 4, 2000 (Washington) -- A controversial new study shows that elderly patients with a mild form of Alzheimer's disease are just as safe on the road as their unimpaired counterparts, at least by one crucial measure. The study compared the crash rates of 63 patients suffering from dementia of the Alzheimer's type (DAT) with those of 58 healthy drivers, looking back at state driving records over a five-year period.
"We found no difference in crash rates between drivers with DAT and controls," write David Carr, MD, and his colleagues from the division of geriatrics and gerontology at Washington University in St. Louis, in an article appearing in the January issue of the Journal of the American Geriatrics Society.
The surprising research comes in the wake of other findings that document a doubling in the rate of DAT every five years in those older than 65 and a tendency for patients with DAT to drive dangerously. "We know that some of these people are safe drivers, at least at this stage," study co-author John Morris, MD, tells WebMD. Morris, director of the memory and aging project at Washington University, emphasizes that these patients are at the very earliest stage of DAT, and their symptoms may be barely detectable.
"We want to allow people to maintain their driving independence as long as they're safe but have them stop just before they demonstrate that they are unsafe," says Morris. For example, he says that mildly impaired patients should be evaluated every six months to see if their driving skills have deteriorated. One predictor might be the ability to execute a left-turn safely. According to Morris, a loss of driving privilege can lead to isolation and a quicker decline in these patients.
In fact, while there were relatively few crashes in the study overall, the accident rate was slightly higher (0.07 per year) for the non-demented group than for those with DAT (0.06 per year for patients with the mild form and 0.04 per year for patients with very mild disease). Even though the results are not statistically significant and those with mild DAT didn't drive as much as the others in the study, the researchers say the data show a trend.