March 28, 2017
When to give up the car keys can be a very difficult decision for anyone in the early stages of Alzheimer’s disease. While those with moderate to severe Alzheimer’s should not be behind the wheel, it can be emotionally wrenching to tell someone in the early stages of the disease that they should give up the independence of driving. Two new studies underscore how difficult it can be to determine the best time to stop driving, a decision that typically must be made on a case-by-case basis.
The first study, published in the Journal of Alzheimer’s Disease, found that no one assessment tool can accurately determine when it is time to give up driving.
For the study, Canadian researchers looked at data from 32 earlier studies on Alzheimer’s and driving. They found that about one in seven, or 14 percent, of those with very mild Alzheimer’s – the earliest stages of the disease — failed a driving road test. About one in three, or 33 percent, of those with mild Alzheimer’s failed a driving road test. That compared to a failure rate of only 1.6 among older drivers who did not have Alzheimer’s or other forms of dementia.
Overall, only about half, or 46 percent, of those in various stages of Alzheimer’s passed a driving road test. About a third of those with Alzheimer’s got a borderline driving test result, while 19 percent failed the test. Some of the road tests involved a computer simulation; others were actual on-road tests.
Four of the studies looked at men and women with mild cognitive impairment, a form of memory loss that often leads to Alzheimer’s disease. Those with mild cognitive impairment showed generally minor impairments in driving skills.
Problems with visual and spatial skills, attention or planningprior to taking the test were strong predictors of who would fail it. But there was great variation in findings among the individual studies, and no one method or test to predict who should stop driving emerged from an analysis of the data.
“Many individuals with Alzheimer’s disease or mild cognitive impairment are at an increased risk of driving collisions and crashes compared to other seniors,” said study co-author Megan Hird, a researcher at the Li KaShing Knowledge Institute of St. Michael’s Hospital at the University of Toronto. “Despite this, some patients are able to retain the ability to drive safely. But the complex nature of these conditions and of driving itself makes deeming a patient an unsafe driver extremely difficult for clinicians.”
She said that doctors and other health-care professionals often are not confident in assessing the driving ability of patients with cognitive impairment, since there is no single valid assessment tool to discern who is safe to drive and who is not.
The second new study, published in the Journal of Nursing, identified certain skill impairments that might make someone in the early stages of Alzheimer’s at higher risk for unsafe driving.
“It is important to note that it’s not a person’s chronological age itself that puts the older driver at increased risk for driving accidents, but rather the changes in functionality and skills needed for safe driving,” said Lisa Kirk Wiese, the study’s first author and an assistant professor at the Christine E. Lynn College of Nursing at Florida Atlantic University.
Memory plays a significant role in driving competence, the authors note. Drivers must remember many things, including how to turn the key in the ignition, shift gears, and distinguish the brake from the gas pedal. Studies show that impairments may be especially apparent in the driver’s inability to drive the car in a straight line or to safely make left-hand turns.
Someone with Alzheimer’s “might say something along the lines of ‘I have never had an accident.,’ ”Dr. Wiese said. But that’s not necessarily a good indicator that someone is a safe driver.
The authors suggest a three-pronged approach to testing for safety in older adult drivers. First, anyone with Alzheimer’s should get a detailed assessment and medication review from a health professional; some drugs can impair driving ability. Second, driving can be tested using a computerized simulation using a touch screen interface. Finally, drivers can take a driving road test with a certified road test examiner.
“The task of identifying and helping older adults who are unaware of a decline in cognition impacting road safety can be overwhelming for family members, “said Dr. Wiese. “Nurses who care for older adults in public health settings can play a vital role in understanding and identifying the cognitive mechanisms that inhibit effective driving and help to identify older adults who may be at risk for unsafe driving, and who would benefit from a driving evaluation.”
Early Alzheimer’s does not mean you must stop driving. But family members should be aware of the risks, and modify driving habits as needed. For example, it may be prudent to avoid driving in challenging conditions, such as during bad weather or when it is dark, or in heavy traffic during rush hour. Highways might be avoided, since high speeds can be an aggravating factor. It may also be a good idea to stick to familiar driving routes.
Experts say that strategies like hiding the car keys are ineffective. Family members, and health professionals, must work with those with Alzheimer’s to determine the safest course of action for all. Regular check-ups are indicated for anyone with Alzheimer’s who is still driving. The American Academy of Neurology recommends a reassessment every six months for people diagnosed with very mild dementia who continue to drive.
By www.ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Marc Flajolet, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Megan A. Hird, Peter Egeto, Corinne E. Fischer, Gary Naglie, Tom A. Schweizer:“A Systematic Review and Meta-Analysis of On-Road, Simulator and Cognitive Driving Assessment in Alzheimer’s Disease and Mild Cognitive Impairment.” Journal of Alzheimer’s Disease, Volume 53, Number 2, pages 713-729, 2016.
Lisa Kirk Wiese, PhD, RN; Logan Wolff, MS: “Supporting Safety in the Older Adult Driver: A Public Health Nursing Opportunity.” Public Health Nursing, published online June 6, 2016.