Abstract
Purpose: :
To characterize visual, cognitive, and other factors amongst those who do and those who do not drive during night time hours in the elderly population.
Methods: :
The Salisbury Eye Evaluation and Driving Study (SEEDS) is a longitudinal study of vision, cognition, and driving behavior of older drivers living in the greater Salisbury metropolitan area. Patients were recruited from a complete listing of all Maryland Department of Motor Vehicle Administration licensees, age 67- 87 years. We report on data from two visits which both included real time driving assessment using a driving monitor system (DMS) which was installed in each participant’s car for a five day period and which monitored driving performance, including time of driving. All participants underwent a battery of cognitive, and visual function testing. Night hours were defined according to seasonal variation. Univariate and multivariate analyses were performed.
Results: :
Complete data was available for 990 of the 1080 participants attending both visits. 61% of participants maintained their driving patterns at both time points (were either night drivers or non-night drivers) while 39% changed their driving patterns between the visits. Increasing age, female gender, poorer visual acuity and contrast sensitivity, were found to be significantly associated with not driving at night. Fewer miles driven and winter season of the participant’s visit were also associated with not driving at night. In multivariate analysis, an association was observed between depression and less night driving in females more so than in males. Participants who were older, had depression (but only in females), had worse performance on a test of visuomotor skills, had poorer contrast sensitivity, and missed more points on visual field testing were less likely to be driving at night.
Conclusions: :
Restricting driving at night is associated with multiple factors. Depression is associated with female drivers restricting driving at night, but not males. Contrast sensitivity loss is a factor in driving at night, and independently, measures of cognitive function affect decisions to drive at night.
Keywords: aging: visual performance • contrast sensitivity • visual fields