A comparison of driving in older subjects with and without age-related macular degeneration
J. P. Szlyk, C. E. Pizzimenti, G. A. Fishman, R. Kelsch, L. C. Wetzel, S. Kagan and K. Ho
Department of Ophthalmology and Visual Sciences, University of Illinois, Chicago Eye Center, USA.
OBJECTIVE: To determine the effects of age and central vision loss on
driving skills. METHODS: Ten subjects with age-related macular degeneration
and average binocular visual acuity of 20/70, and 11 age-similar subjects
with normal vision, were examined with a battery of cognitive and visual
tests, an interactive driving simulator, and an on-road driving test. Data
were collected on the frequency of real-world accidents and convictions for
traffic violations. RESULTS: There were no significant differences between
the two groups on any of the cognitive tests. The age-related macular
degeneration group demonstrated poorer performance on the driving
simulator, including delayed braking response times to stop signs, slower
speeds, and more of both lane boundary crossings and simulator accidents.
The age-related macular degeneration group also demonstrated poorer overall
on-road test performance, including having significantly more points
deducted for driving too slowly and for not maintaining proper lane
position. However, these effects on the simulator and the on-road test did
not translate into an increased risk of real-world accidents for the
age-related macular degeneration group. Significantly more control subjects
than patients with age-related macular degeneration were involved in
self-reported accidents, and significantly more control subjects had state
convictions for traffic violations. There was evidence of compensation in
the age-related macular degeneration group in four major areas: (1) not
driving in unfamiliar areas; (2) traveling at slow speeds; (3)
self-restricting their nighttime driving, and (4) taking fewer risks while
driving (eg, not changing lanes). There was also evidence of compensation
in the older control group. CONCLUSIONS: Vision, simulator, and on-road
test variables combined with subjective risk taking predicted self-reported
real-world accidents in a logistic regression analysis. However, risk
taking, rather than simulator or road-test performance, was the most
significant predictor for both patients with age-related macular
degeneration and the control group.
