The objective of this cross-sectional study in a population-based cohort of community-dwelling older adults was to assess driving self-restriction (vision related and nonvision related) in relation to vision test performance of older adults. Participants were six hundred twenty-nine current drivers aged 55 and older had driving behaviour, health, and physical function assessed and vision function tested in 1993-95. Measurements were self-report of driving restriction as vision or non-vision related and performance on a comprehensive battery of vision tests (visual acuity; contrast sensitivity; effects of illumination level, contrast, and glare on acuity; visual fields with and without attentional load; colour vision; temporal sensitivity; and the effect of dim light on walking ability). Demographic, health, and functional characteristics differed significantly between restrictors and nonrestrictors but not between vision- and nonvision-related restrictors. Controlling for potential confounding, only vision-related driving self-restriction was significantly associated with reduced performance on non-standard measures of acuity. Poor depth perception was significantly associated with restriction for both vision- and nonvision-related reasons. Poor performance on attentional visual field tests, analysed individually and in combination with standard field tests, was not associated with driving self-restriction. It is concluded that older adults with early changes in spatial vision function and depth perception appear to recognise their limitations and restrict their driving even if they do not acknowledge the visual impairment as the cause for restriction. Poor visual attention, a risk factor for crashes, may not be recognised. Additional studies of driving self-restriction in relation to risk factors for crashes in older adults may help refine this strategy of reducing driving-related injury and death. (Author/publisher) For an editorial comment on this paper see C 26455 fo.
Abstract