Driving Under the Influence of Age

Brian R. Ott, M.D.

Many people are living longer, and that means more older drivers are behind the wheel. It is a trend that continues to raise safety concerns on the road. This week is dedicated to Older Driver Safety Awareness.

Older drivers -- the facts

Older drivers have fewer motor vehicle crashes than younger drivers, mostly because they drive less. Per mile, though, crashes increase as people reach their 60s and beyond, at the levels seen in younger drivers. This suggests that age, or age-associated impairments, may be important risk factors.  Consider these statistics:

  • Older adults, especially those over age 75, are more likely than younger drivers to have contributed to a fatal crash.
  • Fatal two-vehicle crashes remain “below average” for drivers 60 to 69, but it rises sharply for older drivers. For drivers 70 to 79, the risk is nearly equivalent to that of teenage drivers, and for those 80 and older, it is four times higher than expected. 

The good news is that the trends show a decline in this risk over the past 20 years, possibly related to better safety standards as well as older drivers being more physically fit than in the past.

Conditions impacting driving safety

It is important to remember that aging itself is not the main problem affecting driving safety, but some medical conditions, that are treatable, may come with age that can impact driving ability for some people.

  1. Vision –  Common eye disorders impacting driving ability are cataracts, macular degeneration, glaucoma and diabetes. 
  2. Motor function --With age, an individual’s speed and coordination diminishes, as does reaction time. Many older Americans also have chronic conditions that can impact their driving ability, like arthritis, diabetes, sleep apnea, seizures, heart rhythm problems and neurological conditions like Parkinson’s diseases.  In many cases, the medication used to treat such conditions can cause problems for drivers as well.
  3. Cognition:  Being alert and having good cognitive function is vital while driving. Memory, visual attention and perception, and decision making are key areas of cognitive function that are important for driving safety. Getting lost is an important safety hazard in itself – especially when an older driver runs out of gas or is otherwise in need of assistance in a hostile or unpopulated area. Unfortunately, approximately one in three older drivers may develop mild cognitive impairment or dementia, and medications used in treatment may also affect their driving. Dementia conditions like Alzheimer’s Disease impact cognition, and present risks as the disease becomes more severe.

Dementia is among the top medical conditions associated with increased risk of car accidents. Beyond year three of the disease, the crash risk increases to that of a teenage male. Men with dementia are at higher risk. Patients with very mild to mild dementia need close monitoring and regular driving competency assessments, every 6 months. Some patients with mild dementia may continue to drive safely for up to a year. Once a physician diagnoses dementia, the question is not “if” a person should stop driving, but rather “when.”

Measuring driving ability

While the American Medical Association offers guidelines for physicians on the best ways to assess and monitor the older driver, guidelines and office-based measures do not predict crash risk with a high degree of accuracy!  They may offer “red flags,” but problems identified through such office screening tests cannot alone be used to make a final recommendation on the need to retire from driving.

Cognitively impaired older drivers are often unaware of their driving and other functional limitations, so it is important for the physician to recognize a driver with early dementia and provide appropriate guidance on driving restrictions when necessary.  You or another family member or friend should accompany a loved one to his or her appointments because patients may not accurately report their driving abilities and experiences.

Physicians also have access to other specialized assessments and performance-based testing that can be used to help in decision making. A formal road test may be recommended, but that testing is expensive, and may not be an affordable option for all families.

Here are other resources:

  • Occupational therapists trained as driving rehabilitation specialists, and some driving school specialists experienced with older drivers, can evaluate driving risk as well as provide advice on improving driver safety.  A referral from your physician may be needed to see an occupational therapist. The Lifespan Occupational Therapy program offers a driving evaluation program.
  • AAA Mature Operator courses are defensive driving courses designed to meet the information needs and interests of senior drivers over 55 years of age. Drivers who successfully complete the driver improvement program also might be eligible to receive insurance premium discounts. 
  • AARP Driver Safety’s Driving Resource Center is an interactive online resource for course participants that features tools and activities, including driving simulations, state-specific rules of the road and new vehicle technologies.
  • CarFit is an educational program created by the American Society on Aging. It can help older drivers find out how well they currently fit their personal vehicle, because proper fit can increase driver safety. Similar services can be provided by a driving rehabilitation specialist.
  • The Alzheimer’s Association emphasizes driving ability, not just diagnosis, to determine when and if a person should retire from driving. The association offers important information for spouses and families.

Plan for the future

In my experience working with patients and families, gradually reducing driving when necessary is less emotionally traumatic for the driver and is usually more successful than abruptly ending one’s driving privileges. Before recommending driving cessation, it is best to have completed medical evaluations related to driving so that you feel confident that it is time.  This step will present a loss of autonomy – and will also be accompanied by emotional and practical implications for the driver. These are all things that will need to be addressed.