Edition: U.S. / Global

Some Caution Signals for Older Drivers

Published: February 20, 2001

Last summer, as a 72-year-old friend exited from a strip mall in Connecticut, her car was struck broadside by an van she had not seen coming. She died three days later of complications related to her injuries.

Just one year earlier, a 70-year-old woman I know was in a similar accident. She pulled out of a filling station on Long Island into the path of a semi. Her husband eventually died from his injuries; she survived, but after many hospitalizations and with permanent disabilities.

Both of these accidents could have happened to younger drivers, to be sure. But the chances are much greater that an older driver will fail to see an oncoming vehicle and be able to react in time to avoid a collision.

And as the population ages — by the year 2020, one in five drivers will be 65 or older — the potential for debilitating and fatal accidents among older drivers (and their innocent victims) will grow accordingly unless everyone recognizes the limitations inflicted by advancing age and takes steps to compensate for them. No group but teenagers has more accidents or a higher vehicular fatality rate per mile driven.


Now, nearly half of older drivers live in suburban areas and more than a quarter live in rural areas where motor vehicles are needed to reach shopping and services and where public transportation is either sparse or nonexistent. And there are often no family members nearby or friends available to provide the needed rides.

Many groups — AAA, AARP, city and state departments on aging and traffic safety, the National Institute on Aging, among others — have developed informative packets, booklets and safe driving courses. And, they continue to press for improvements in vehicular design and road safety features, all intended to keep older drivers on the road safely.

If you know which physical and mental changes that accompany advancing age can affect the ability to drive in comfort and safety, you can better appreciate the value of the recommendations and have an easier time assessing whether it is wise for you or the older people in your life to continue driving.

Common Effects of Aging

You need not have any chronic illnesses or obvious disabilities for the effects of aging to affect your driving skills. Here is what happens to virtually everyone:

VISION DEFICITS Driving experts say that 90 percent of the information needed to drive safely is visual. Yet, as people get older, four crucial visual abilities diminish: visual acuity — the ability to see clearly what is ahead of you, especially at night; peripheral vision — the ability to see what is happening to the left and right while looking straight ahead; accommodation — the speed with which your eyes adjust to changes in light and dark and near and far images, and depth perception — the ability to judge how fast other cars are moving.

Furthermore, older people are more prone to being temporarily blinded by the glare of headlights, either from cars and trucks coming toward them or in their mirrors from vehicles behind them. A 55-year- old person takes, on average, eight times longer than a 16-year-old to recover from glare. Colors, especially red, become harder to see with age. Some older drivers take twice as long as younger drivers to recognize the flash of brake lights.

Other common age-related deficits include eye muscle dysfunction, which impairs the ability to scan the driving environment, and poor contrast sensitivity, which can make it hard to detect curves in the road, see a gray vehicle at an intersection or a pedestrian at a crosswalk or see clearly in bad weather.

According to the AAA Foundation for Traffic Safety, the amount of light needed to drive doubles about every 13 years. That means a 60-year-old driver needs about 10 times as much light as a 19-year-old to see clearly.

BODY CHANGES Few people over 65 need to be told that with advancing age joints tend to stiffen, making it more difficult to turn one's head when pulling out of a parking area or when backing up. Muscles gradually weaken, and that weakening can impair a person's ability to steer and brake. Reaction time slows, increasing the response time when faced with any sort of road hazard, especially a vehicle that suddenly stops or turns in front of you.

And hearing deficits common in older people can affect their ability to detect and respond appropriately to the sirens of emergency vehicles, railroad crossing signals and the warning horns of other drivers.

COGNITIVE CHANGES Your mind may be just as sharp but it works more slowly as you get older. Thus, in addition to having slower reflexes, older people tend to have greater difficulty doing more than one thing at a time — absorbing new information from their surroundings and reacting accordingly. Older drivers also are more easily distracted by noise or other disturbances, including the radio and the conversation of others in the car.

COMMON HEALTH PROBLEMS Then there are a host of disorders that become increasingly common with age that can further limit your ability to handle a motor vehicle safely.

To the normal effects of aging on the eyes may be added such problems as cataracts (a clouding of the lenses that impairs visual acuity and increases sensitivity to glare), macular degeneration (a gradual loss of central vision) and glaucoma (increased eye pressure that limits peripheral vision). Other common age-related disorders that can impair driving skills include arthritis, diabetes, insomnia, Parkinson's disease, heart rhythm abnormalities, stroke, depression and dementia.

Movements needed to handle a motor vehicle safely can be limited in someone with arthritis or Parkinson's disease or a person who has suffered a stroke.

Diabetes can cause vision-impairing eye damage (diabetic retinopathy) and, among those with widely fluctuating blood sugar levels, can sometimes result in a loss of consciousness. Irregular heart rhythms can cause dizziness while driving, and chronic insomnia can diminish alertness and increase the risk of dozing off at the wheel.

Depression, which may limit a person's ability to pay attention and to obtain restful sleep, can also impair driving skills. And the gradual onset of dementia can cause memory problems and behavioral difficulties that make safe driving problematic, yet dementia and its effects are usually not recognized by the affected person.

Many of the medications taken to treat the various infirmities of age can further diminish driving skills.

Older drivers are likely to be taking many more prescription and over-the-counter drugs than their younger counterparts.

Although people over 65 represent about 11 percent of the population, they use 25 percent of all prescription drugs, plus a host of nonprescription remedies.

Drugs that can interfere with safe driving include sleep aids, antidepressants and antianxiety drugs, painkillers, antihistamines, cough and cold remedies and insulin and other drugs used to treat diabetes.

Alcohol, which is also a drug, can have an ever worsening effect on driving skills as people age. With advancing age, tolerance for alcohol steadily declines — a person gets tipsy on less and less alcohol — and the effects of alcohol last longer.

Next week : Compensating for the effects of age on driving ability.