A COMPARISON OF DRIVING IN OLDER SUBJECTS WITH AND WITHOUT AGE-RELATED MACULAR DEGENERATION

Objective: To determine the effects of age and central vision loss on driving skills. Methods: Ten subjects with age-related macular degener ation and average binocular visual acuity of 20/70, and 11 age-similar subjects with normal vision, were examined with a battery of cognitiv e and visual tests, an interactive driving simulator, and an on-road d riving test. Data were collected on the frequency of real-world accide nts and convictions for traffic violations. Results: There were no sig nificant differences between the two groups on any of the cognitive te sts. The age-related macular degeneration group demonstrated poorer pe rformance on the driving simulator, including delayed braking response times to stop signs, slower speeds, and more of both lane boundary cr ossings and simulator accidents. The age-related macular degeneration group also demonstrated poorer overall on-road test performance, inclu ding having significantly more points deducted for driving too slowly and for not maintaining proper lane position. However, these effects o n the simulator and the on-road test did not translate into an increas ed risk of real-world accidents for the age-related macular degenerati on group. Significantly more control subjects than patients with age-r elated macular degeneration were involved in self-reported accidents, and significantly more control subjects had state convictions for traf fic violations. There was evidence of compensation in the age-related macular degeneration group in four major areas: (1) not driving in unf amiliar areas; (2) traveling at slow speeds; (3) self-restricting thei r 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 varia bles combined with subjective risk taking predicted self-reported real -world accidents in a logistic regression analysis. However, risk taki ng, rather than simulator or road-test performance, was the most signi ficant predictor for both patients with age-related macular degenerati on and the control group.