The aging of America brings questions surrounding the ability of older Americans to drive safely.

Posted on December 14, 2001 at 8:47 a.m.

BIRMINGHAM, AL — The aging of America brings questions surrounding the ability of older Americans to drive safely. UAB (University of Alabama at Birmingham) researchers are at the forefront of answering those questions, designing a research program through the national Centers for Disease Control and Prevention (CDC) to gain greater insight into who is at risk of being involved in motor vehicle collisions.

Researchers at UAB’s Center for Injury Sciences and the departments of epidemiology and ophthalmology have received a grant from the National Center for Injury Prevention and Control at the CDC to design a national study examining older driver’s needs, habits and risks. Among the study’s goals are determining how frequently older people drive and why they stop or curtail their driving. The study also hopes to understand which medical conditions or medications increase crash risk, as well as find alternatives to driving that are practical and acceptable to older persons who do not or should not drive.

“Little is known about how the physical changes that accompany aging affect driving performance,” says Gerald McGwin Jr., Ph.D., assistant professor of epidemiology and surgery and associate director of the Center for Injury Sciences who is designing the research protocol. “The extent that medical conditions such as cardiovascular disease or central nervous system disorders can affect an older person’s ability to drive is also poorly understood.”

Adults aged 65 and older represent 13 percent of the U.S. population but constitute 17 percent of all motor vehicle-related deaths. Each year approximately 4,000 older drivers are killed, and another 175,000 are non-fatally injured in crashes. More than 50 million older persons will be eligible to drive in 2020, including 22 million persons aged 75 or above.

“Individual states have developed their own criteria for determining if older persons should drive and many methods used to identify high-risk drivers have not been scientifically proven,” says McGwin. “There is a need for practical, science-based information for state governments to use when making policy.”

McGwin and co-researcher Cynthia Owsley, Ph.D., a professor of ophthalmology, say that it appears that many older drivers self-regulate their driving by not driving at night, during rush hour or in bad weather.

“The bulk of the research about the driving habits of older persons and any additional risk they are under for a crash suffers from several methodological flaws,” says Owsley. “It is impossible to make definitive answers to whether medical conditions, medications or functional ability affect driving. In order to move the science forward, research is needed that builds upon previous understanding and is able to use information from many sources simultaneously, such as medical records, motor vehicle records, measures of the number of miles driven, and individual characteristics.”

McGwin says UAB is in a unique position to spearhead this effort. “Dr. Owsley and her colleagues in the UAB Driving Assessment Clinic are pioneers in assessing crash risk in older drivers and in educating older drivers about how to enhance their driver safety. Our Center for Injury Sciences has a great deal of experience in understanding the causes and severity of crashes, from vehicle design to driver behavior.”

McGwin says the study would enroll a large, nationally representative sample of consenting older adults and following them over several years. Researchers would look at medical fitness, functional ability, personal characteristics and driving behaviors.