FRIDAY, May 20, 2011 (HealthDay News) -- Even healthy seniors with safe driving records and no history of dementia tend to make more potentially dangerous errors, such as forgetting to check a blind spot, according to a new study.
This suggests that driving performance declines with normal aging and more mistakes crop up, putting the elderly at risk of automobile crashes, said the Australian researchers, who suggested additional training in related cognitive skills for older drivers.
That suggestion, however, will likely be controversial.
"It's really hard to re-train the brain," said Renee Pekmezaris, vice president for community and health services in the Research Department of Population Health at North Shore Long Island Jewish Health System in New York.
Other studies show that cognitive re-training does not reduce older people's driving crashes, said Pekmezaris. "I'm not as hopeful as the study authors about that," she said. "But there are other things we can do."
The study appeared online May 16 in Neuropsychology, a journal of the American Psychological Association.
In the study, researchers examined the driving habits of 266 healthy drivers ranging in age from 70 to 88 who lived independently and drove at least once a week. Besides completing questionnaires about their health and driving history, the elders took tests on various driving skills such as discrimination, reaction time and the ability to stay focused amid distractions or adapt to changing conditions.
During the 12-mile road test, a professional instructor with access to a brake rode in the car. An occupational therapist sat in the back seat and scored the drivers for skills such as using signals and mirrors, checking the "blind spot" and problems that included veering, tailgating, inappropriate braking and accelerating.
Overall, 17 percent of the drivers made serious mistakes that required the instructor to grab the steering wheel or apply the brake.
The rate of critical mistakes among drivers aged 85 to 89 (who had an average of almost four critical mistakes) was also four times higher than among those 70 to 74 years old (who had an average of less than one).
The most common error was a failure to check the "blind spot" for other vehicles. Drivers reporting a previous crash on the questionnaire made more errors connected to observation, and scored lower on appropriate braking and acceleration, the study found.
Men and women performed equally well on the tests.
"The results fit well with about 30 years of previous research," said Harvey L. Sterns, a research professor of gerontology at Northeastern Ohio Medical University. Driving ability, in general, declines with age, he said.
But Sterns cautioned that many elderly have no problems handling a car. Some drivers in the oldest age group studied made no errors, he said.
"There are greater differences within age groups than between age groups," said Sterns, also a professor of psychology at the University of Akron in Ohio. "It's hard to know whether [the study is] showing dramatic changes relative to an earlier time."
In the United States, 33 million drivers aged 65 and older were on the roads in 2009, according to the U.S. Centers for Disease Control and Prevention. On average, 500 elderly adults are injured every day in car accidents, the agency reported.
As the population ages, the issue will increase in significance, said Sterns. Pinpointing cognitive functions that are linked to driving skills is "an important first step," he said, noting some of these functions could be improved with training.
The authors said their findings are useful for those designing roads and signs, although they acknowledge their study has limitations. One is that drivers' vision wasn't evaluated.
Pekmezaris said aging drivers might do well to modify their driving habits and take advantage of technological advances.
Older drivers may need to restrict their driving to daylight hours, and make use of anti-glare equipment and onboard anti-collision devices, she said.
"What we really need is to get physicians involved in this," said Pekmezaris. Earlier research found that 89 percent of elderly drivers reported they would stop driving if their doctors recommended it, she said.
To learn more about elderly drivers, visit the U.S. Centers for Disease Control.