Driving is essential for most older adults to maintain their autonomy. In the US, about 20 million drivers are ≥ 65. This number is expected to more than double by 2020.

Safe driving requires the integration of complex visual, physical, and cognitive tasks, and older drivers may have mild to moderate deficits in these domains. Many older drivers successfully self-regulate their behavior and compensate for deficits by avoiding rush hour, driving fewer miles per year, limiting trips to shorter distances, and avoiding driving during twilight, nighttime, or bad weather. Also, older drivers tend to be more cautious, drive more slowly, and take fewer risks. However, some older adults, whether because of denial, dementia, or a strong desire to maintain independence, continue to drive despite significant impairments in driving ability.

Older drivers on average have a lower annual incidence of crashes with injury (rates per 1000 licensed drivers—see Fig. 1: The Older Driver: Number of crashes per licensed driver by age (2003).) than drivers of all other ages. However, because the number of miles driven per year also declines with aging (see Fig. 2: The Older Driver: Annual mileage by age and sex (2001).), the crash rate per mile for drivers ≥ 70 is higher than that for drivers of all other ages except those < 20.

Fig. 1
Adapted from Houser AN: Older drivers and automobile safety. AARP Public Policy Institute, August 2005. Available at www.aarp.org/family/articles/older_drivers_and_auto_safety.html. Accessed 10/21/09. Number of crashes per licensed driver by age (2003).

Fig. 2
Adapted from a figure courtesy of John Eberhard, based on Bureau of Transportation Statistics, 2002. Annual mileage by age and sex (2001).

Most crashes involving older drivers occur during the daytime and on weekdays. These crashes often result from failure to yield the right-of-way or heed a stop sign or red light and tend to occur while going through intersections, making left turns, or merging into traffic. Crashes are more likely to involve multiple vehicles and to result in serious injuries and fatalities. Unlike in younger drivers, alcohol and speeding rarely play a role.

When crashes do occur, older adults seem to be more vulnerable to injury because

• They have less capacity to withstand trauma.
• They often have more comorbidities.
• Many crashes are driver-side impact (eg, occur while making left turns), making the driver more likely to be injured.
• They are more likely than younger drivers to drive very old cars without air bags or other improvements in crash protection.

However, as cars have become more crashworthy and other efforts have improved traffic safety, the crash fatality rate of older adults has decreased over the past decade.

Assessment

Health care practitioners become involved in driving decisions when deficits are identified during routine examination, when family members express concern, when law enforcement cites unsafe driving behaviors, or when patients solicit advice. The role of practitioners is to do detailed functional and medical assessments related to driving safety.

Driving history should be reviewed; details of driving habits and past violations, accidents, close calls, or getting lost may point to general or specific impairments. Some impairments may obligate practitioners to refer a patient to the state Department of Motor Vehicles for additional testing or driving restrictions. (See the National Highway Traffic Safety Administration's [NHTSA] Physician's Guide to Assessing and Counseling Older Drivers for state licensing requirements and reporting regulations.)

Key Points

• The number of older adults is growing rapidly.
• Driving cessation is inevitable for many and can have negative outcomes (eg, social isolation, depression, fewer driving destinations).
• Age-related and disease-related changes in physical and cognitive function can impair driving ability and account for some of the increased crash rate per miles driven.
• Many older drivers successfully self-regulate their behavior.
• Older adults are more vulnerable to injury in a crash than younger adults.
• The role of practitioners is to do functional and medical assessments, which determine overall driving safety, and to communicate recommendations effectively to older drivers and their family members.
• State licensing requirements and reporting regulations that pertain to older drivers are available from the NHTSA.

Last full review/revision October 2009 by David B. Carr, MD; Peggy P. Barco, MS, BSW, OT/L