When Alzheimer’s Patients Should Not Drive

It’s one of the most difficult decisions some families are forced to make:  when is it time for a loved one with Alzheimer’s disease to stop driving?

The fact that much of the country lacks public transportation can make the decision all the more challenging, since quitting too soon restricts independence for those who otherwise may function well for many years. 

“That’s a real cost to the individual and family and society,” Jeffrey Dawson of the University of Iowa told the Associated Press.

Dawson, a biostatistics professor, and his team have created a test to show when a person may be a danger on the road.

“You have to have some sort of trade-off between the individual’s independence along with the safety of the driver and with other people on the road,” he said.

Experts say patients usually begin by gradually scaling back their driving — avoiding night trips, busy freeways or left-turn intersections, for example.

Sue Pinder, 58, an adviser with the Alzheimer’s Association, recently gave up driving in large cities despite the fact it meant fewer visits to her daughter in Dallas.

Shortly after Pinder was diagnosed in 2004, she designated her husband to make the ultimate determination on when she would quit driving.  For her last birthday, he gave her a GPS system, which helped Pinder navigate unfamiliar streets. 

“That’s helped a lot where I don’t have to worry, I can concentrate on my driving and not the directions,” Pinder told the AP.

Working on ways to help other patients in similar circumstances, Dawson’s team developed an sophisticated behind-the-wheel exam consisting of a 35-mile drive through urban, rural and residential streets in a customized Ford Taurus able to record nearly every action the driver takes.  The modified car works much like an airplane “black box”.  Small video cameras were also positioned to show oncoming traffic as well.

Researchers recruited 40 participants with early-stage Alzheimer’s who still had their driver’s licenses to take the road test, and compared their results with 115 older drivers without dementia who took the same test.

The study’s results were remarkable, with the Alzheimer’s drivers on average committing 42 safety mistakes, compared with just 33 for the other drivers.

Lane violations, such as swerving as another vehicle approached, were the most common problems for the Alzheimer’s drivers, who performed 50 percent worse.

Total errors increased with rising age, regardless of whether or not the driver had Alzheimer’s.  Indeed, an additional 2 1/2 mistakes were made for every five years of age.

However, some Alzheimer’s patients drove just as well as their healthy counterparts, Dawson emphasized.

The team also checked whether any of the large number of neuropsychological tests given before the test had accurately predicted who would drive worse, which some did.

Flunking basic memory tests didn’t make a difference, the researchers found.  But standard neurological tests of multitasking abilities did.  These tests assess if people’s visual, cognitive and motor skills work together rapidly to make quick decisions.

Examples include showing Alzheimer’s patients geometric figures for a few seconds, and then having them draw the shape from memory.  Other tests had patients drawing paths between a sequence of letters and numbers.

Patients who scored average or better on those kinds of written tests were no worse drivers than other older drivers, the study found.  However, Dawson said those who scored worse than average tended to commit about 50 percent more errors on the road.

Although additional research is needed, the researchers’ ultimate goal is provide a simple doctor’s-office exam to help guide when patients should stop driving.

Each year, roughly 600,000 elderly adults stop driving for some health reason, according to an AP report citing data from the National Institute on Aging.  However, there’s little guidance for the 2 million people estimated to be in early stage Alzheimer’s, and the disease is expected to surge in the next twenty year as the general population ages.

States laws vary on when aging drivers must pass a road test for a license renewal, but they rarely address specific diseases.  California currently requires the reporting of all Alzheimer’s diagnoses so driving ability can be determined.   The Alzheimer’s Association also warns families of signs of potentially unsafe driving. 

One particular challenge is that as the condition worsens, patients often passionately deny that they’re a danger on the road, according to Dr. Gary Kennedy, head of geriatric psychiatry at New York’s Montefiore Medical Center.

“I can be the bad guy,” he says to families, sometimes advising relatives to disable a car, or reporting patients to the state Department of Motor Vehicles for a driving test.

“Giving up the car is not like going into the nursing home,” Kennedy tells his patients.

“If as a society we recognize this as a danger, we need to help them compensate,” he told the Associated Press.

The study was reported in the journal Neurology.

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