with younger drivers, older drivers are less likely to drink and drive and to
cause an accident resulting in a fatality.1 However, the safety of
older drivers is a public health concern, since motor vehicle accidents are a
leading cause of injury-related deaths in adults 65 and older. 2,3
Furthermore, the fatality rate for drivers 85 and older is nine times higher
than that of drivers ages 25 to 69.3 Older drivers are considerably
more fragile than their younger counterparts and are therefore more likely to
suffer a fatal injury in the event of a crash.
Many older adults report that
maintaining the ability to drive represents independence, freedom, competence,
control, and even safety, since public transportation options are often
thought to be less safe.4 Pharmacists can attest, however, to
encountering community-dwelling seniors who continue to drive despite being
physically limited or cognitively impaired as a result of medications or
medical conditions (Table 1 ). For example, polypharmacy, which is a
frequent occurrence among seniors, is associated with increased rates of
potentially inappropriate medication use and dangerous drug interactions,
which in turn are associated with worse physical function and pain in elderly
patients.5 Many medications commonly used by geriatric patients may
cause cognitive and/or visual impairment. In addition, alcohol consumption can
alter the body's reaction to medications, thereby altering a variety of
functions in the body.6 While family members and caregivers may
feel relief when an elderly loved one is no longer driving, many seniors may
experience mixed emotions, such as a loss of independence and embarrassment,
upon relinquishing this privilege.
Physicians play an important
role in the safe mobility of their older patients. The American Medical
Association encourages physicians to make driver safety a routine part of
their geriatric medical services. Other health care professionals who serve
seniors, including pharmacists, should educate the public about available
resources and programs that assist with this issue. Pharmacists' skills and
access to seniors leave them particularly well positioned to broach this
subject with these individuals, their families, and their caregivers and to
participate in risk assessment.
In the United
States, the possession and renewal of a driver's license by an older
individual is regulated by laws that vary from state to state, often differing
in areas of renewal intervals (i.e., shorter vs. longer periods), renewal
process (i.e., in person vs. via mail or electronic renewal), and requirements
(e.g., routine vision and road tests).7 Older adults are expected
to make appropriate decisions about when to stop driving; however, the
hardships imposed on seniors by not driving are not widely recognized.8
One study assessed whether not driving is an independent risk factor for
entering long-term care institutions. Results indicated that having no other
drivers in the house was an independent risk factor for long-term care entry.
8 The researchers suggested that innovative strategies aimed at
improving existing transportation options for older adults be considered.8
Driving is a complicated skill
that can be affected by multiple factors, including physical and mental health
and the quality of the driving environment, such as road conditions and
signage.6 Drivers need to be able to visually interpret traffic and
road conditions, cognitively recognize images and decide how to react to a
situation, and perform the physical movement required to control the vehicle.
9 While age alone is not a good indicator of driving skill, changes that
take place during the aging process commonly affect sensory perception,
cognition, and physical and psychomotor functions, thereby impairing a
senior's ability to drive. Medical conditions and medications (Table 1
) can impair one or more of these functions.6 Usually, these
changes occur slowly over a prolonged period of time, and a senior is often
capable to compensate for minor deficits. If, however, several skill areas are
affected, or if there is a sudden change in abilities due to illness or
disease, driving skill may become impaired. The Association for Driver
Rehabilitation Specialists recommends an evaluation if the driver or the
passenger(s) notice any warning signs of impaired driving ability (Table 2
Driving is a highly
visual task, and visual impairments, such as declines in night vision, may
occur as early as age 40.9
Elderly individuals tend to
experience a decline in adequate visual acuity and field of vision due to an
increase in the incidence of conditions such as cataract, glaucoma, macular
degeneration, and stroke.3 Additionally, impaired contrast
sensitivity, glare, and an increase in time to adjust to changes in lightness
and darkness are commonly experienced by senior drivers.3 When
visual function has been compromised, older adults might place restrictions on
their driving (e.g., reducing mileage and avoiding certain high-risk driving
situations) in an effort to improve safety.10,11 One prospective
study demonstrated that older adults with worse scores in multiple measures of
vision (e.g., acuity, contrast sensitivity, central or lower peripheral visual
fields) are more likely to stop driving. 10 Researchers noted that
impairments of contrast sensitivity and visual fields are most associated with
driving cessation.10 Another study found that severe contrast
sensitivity impairment due to cataract elevates at-fault crash risk among
older drivers, even when present in only one eye.12
Cataract is a leading cause of
vision impairment in older adults, affecting almost half of those older than
75. One study found that compared with older drivers without cataract, those
with cataract were (1) approximately two times more likely to report
reductions in number of days driven and destinations per week, a slower
driving speed compared with general flow of traffic, and a preference for
having someone else drive; (2) five times more likely to have received advice
about limiting their driving; (3) four times more likely to report difficulty
with challenging driving situations, and thus two times more likely to reduce
their driving exposure; and (4) 2.5 times more likely to have a history of
at-fault crash involvement in the previous five years.13 The
researchers concluded that older drivers with cataract experience not only a
restriction in their driving mobility but also a decrease in their road safety.
A reduction in the size of the
visual field has been implicated as a major cause of automobile accidents
involving drivers of advanced age.14 Drivers with deficits of
peripheral vision have collision rates twice as high as those with normal
peripheral visual fields.15 Age-related reduction in visual acuity
in the periphery is attributed to neuron loss in the peripheral retina,
presenting with difficulty in driving at twilight due to the peripheral
retina's sensitivity to decreased light.
degeneration is the leading cause of severe and irreversible vision loss in
the Western world. More specifically, it is the leading cause of vision loss
in Americans 60 and older.15 According to one study, while some
seniors with poor vision secondary to age-related maculopathy continue to
drive, their driving exposure tends to be low, and they report avoiding
challenging on-road situations. Findings suggest that their driving status is
related to better eye visual acuity and vision-specific health-related quality
of life.16 More than 50% of the drivers in the study reported that
due to their vision, they had difficulty driving or did not drive at all at
night, during rush hour or in heavy traffic areas, in the rain, or on freeways
or interstate highways.16
Driving requires a variety of
high-level cognitive skills, including memory, visual processing, attention,
and executive skills.3 Certain medical conditions (e.g.,
dementia) and medications (e.g,. benzodiazepines, antipsychotics) commonly
impact cognition in the elderly (Table 1).3,17 While
individuals with early dementia may be able to continue driving, they can
easily become lost or confused in congested traffic.7 The ability
to make quick decisions and coordinate driving skills may become more
difficult as dementia progresses.7 These individuals may become
unable to interpret visual or auditory sensory input. Patients with dementia
reach a point at which it is no longer safe to drive. While some individuals
stop driving on their own, others may require intervention (e.g., persuasion,
convincing, removal of car keys) to prevent the continuation of driving.
Prior to the act of driving, motor
abilities are needed to enter the car safely and fasten the seatbelt.3
Muscle strength, endurance, flexibility, and proprioception are examples of
motor abilities that are necessary for controlling a vehicle and turning the
body to view traffic.3 Age-related changes and musculoskeletal
diseases (e.g., arthritis) can decrease an individual's ability to drive
comfortably and safely.3 Functional declines render senior drivers
vulnerable to crashes in complex situations that require good visual
perception, attention, and rapid response. This has resulted in elderly
drivers being more likely to experience crashes at intersections, particularly
when left-hand turns are involved.3
A stroke can affect the
necessary skills for driving independently. The majority of stroke survivors,
however, can return to independent driving.18 To assist with
physical problems, adaptive equipment is available, such as a spinner knob
(i.e., a device that is attached to the steering wheel to allow controlled
steering with the use of one hand) and a left gas pedal (for those unable to
use the right foot).18 To safely use these types of equipment and
adapt to new driving methods, training is essential.
Driver Evaluation and
Age alone should
not determine one's ability to drive. It is capacity, not age, which
determines driving fitness.19 Driving ability, however, is not
simple to assess. An evaluation by a driver rehabilitation specialist can be
of great value in helping to make the difficult decision as to whether or not
a senior should continue driving. A driver evaluation will assess the
components of driving that may be compromised in the case of a progressive
condition and focuses on the areas of memory, attention, processing speed,
visuospatial functioning, decision making, judgment, planning, and behavior.
The comprehensive assessment would address factors such as medical and
medication history (Table 2) that aid in determining a senior's ability
to drive. Following the evaluation, the driver rehabilitation specialist makes
specific recommendations regarding driving.
Since it is important to plan
for the future, discussing driver ability and safety is recommended while an
individual has the insight needed to participate in the decision-making
process.20 Therefore, experts recommend that an evaluation be
sought when a diagnosis or problems first arise to ensure that compensatory
modalities are utilized to help maintain safe driving and to set limits in
preparation for discontinuation of driving.20
The Automobile Association of
America hosts an informative Web site that is dedicated to helping seniors and
their family members cope with the inability to drive and to ensuring that
seniors are able to remain active and mobile.21 The site addresses
the transition to "giving up the keys," supplemental transportation programs,
and assistance with locating programs. It also discusses how to use mass
transit and options for "Paratransit" for people with disabilities. The
American Medical Association, in cooperation with the National Highway Traffic
Safety Administration, developed the Physician's Guide to Assessing and
Counseling Older Drivers, which includes continuing medical education
self-study and evaluation.
Driving is a complex activity that
requires skill and adequate function of vision, cognition, and mobility.
Age-related changes in perception, processing abilities, and physical
functioning can make driving unsafe. When seniors drive beyond their physical
or cognitive ability, public safety is jeopardized. Pharmacists can take an
active role in this important public safety issue by assessing the risk of
impaired driving ability due to certain medications. Furthermore, due to their
accessibility to seniors, pharmacists are well positioned to point out the
availability of driver assessment, adaptive devices, and resources that
provide education and guidance to seniors and their caregivers.
1. Myths About Older Drivers.
American Society on Aging. Available at:
www.asaging.org/cdc/module4/phase1/phase1_1a.cfm. Accessed November 29, 2006.
2. National Center for Injury
Prevention and Control. Falls and Hip Fractures Among Older Adults. [fact
sheet]. Office of Statistics and Programming. Available at:
www.cdc.gov/ncipc/factsheets/falls.htm. Accessed April 11, 2006.
3. Older driver safety. American
Medical Association. Available at:
www.ama-assn.org/ama/pub/category/8925.html. Accessed November 29, 2006.
4. The Effects of Income on
Mobility. American Society on Aging. Available at:
www.asaging.org/cdc/module4/phase2/phase2_3a.cfm. Accessed November 29, 2006.
5. Zagaria ME. Polypharmacy and
potentially inappropriate medication use in the elderly: across the
practice-setting spectrum. US Pharmacist. 2006;31(10):112-116.
6. What Factors Affect Driving
Ability with Aging? American Society on Aging. Available at:
www.asaging.org/cdc/module4/phase2/phase2_2.cfm. Accessed November 29, 2006.
7. Beers MH, Jones TV, Berkwits M,
et al, eds. The Merck Manual of Health & Aging. Whitehouse Station,
NJ:Merck Research Laboratories; 2004:31, 310, 314, 826-830, 886.
8. Freeman EE, Gange SJ, Munoz B, et
al. Driving status and risk of entry into long-term care in older adults.
Am J Public Health. 2006;96(7):1254-2159.
9. Kaplan W. The occupation of
driving: legal and ethical issues. Physical Disabilities Special Interest
Section Quarterly. Bethesda, MD: American Occupational Therapy
10. Freeman EE, Munoz B, Turano KA,
et al. Measures of visual function and time to driving cessation in older
adults. Optom Vis Sci. 2005;82(8):765-773.
11. Freeman EE, Munoz B, Turano KA,
et al. Measures of visual function and their association with driving
modification in older adults. Invest Ophthalmol Vis Sci. 2006
12. Owsley C, Stalvey BT, Wells J,
et al. Visual risk factors for crash involvement in older drivers with
cataract. Arch Ophthalmol. 2001;119(6):881-887.
13. Owsley C, Stalvey B, Wells J, et
al. Older drivers and cataract: driving habits and crash risk. J Gerontol A
Biol Sci Med Sci. 1999;54(4):M203-M211.
14. Zagaria ME. Visual consequences
of the aging eye. US Pharmacist. 2002;27(8):33-36.
15. Five Vision Topics Added to
NIHSeniorHealth Web Site. National Institutes of Health (NIH). Available at:
www.nih.gov/news/pr/jun2005/nia-20.htm. Accessed September 26, 2005.
16. DeCarlo DK, Scilley K, Wells J,
et al. Driving habits and health-related quality of life in patients with
age-related maculopathy. Optom Vis Sci. 2003;80(3):207-213.
17. Semla TP, Beizer JL, Higbee MD.
Geriatric Dosage Handbook. 10th ed. Cleveland: Lexi-Comp, Inc.;
18. Driving and Stroke. The
Association for Driver Rehabilitation Specialists. Available at:
www.aded.net/i4a/pages/index.cfm?pageid=310. Accessed November 29, 2006.
19. Fitzpatrick, C. To Drive or Not
to Drive. Safe at Home: A Multidiciplinary Approach to Keeping Seniors in the
Community. American Society of Consultant Pharmacists 37th Annual Meeting,
Phoenix Arizona, November 16, 2006.
20. Driving and Alzheimer's. The
Association for Driver Rehabilitation Specialists. Available at:
http://www.aded.net/i4a/pages/index.cfm?pageid=301. Accessed November 29,
21. For Families and Individuals.
American Automobile Association Foundation for Traffic Safety. Available at:
www.seniordrivers.org. Accessed November 29, 2006.
22. Martin S. Common Medications Can
Impair Driving. WebMD Medical News. Available at:
www.webmd.com/content/article/21/1728_54310. Accessed December 6, 2006.
23. Aging and Driving Fact Sheet.
The Association for Driver Rehabilitation Specialists. Available at:
www.aded.net/i4a/pages/index.cfm?pageid=1. Accessed November 29, 2006.
To comment on this article, contact