Examination of cognitive and instrumental functional performance as indicators for driving cessation risk across 3 years.

PURPOSE: The purpose of this study was to prospectively examine the role of cognitive and instrumental functional performance in driving cessation while simultaneously accounting for any contributions of demographics, vision, physical performance, and health among a sample of older adults without dementia.

DESIGN AND METHODS: Included in the analyses were 1,838 participants from the Advanced Cognitive Training for Independent and Vital Elderly (ACTIVE) study who were drivers at baseline and completed the third-year assessment. Participants completed baseline assessments of sociodemographic characteristics, health, sensory function, physical function, cognitive abilities, instrumental functional performance, and depressive symptoms. Driving status was again ascertained 3 years later.

RESULTS: We used Cox proportional hazard analyses to examine prospective predictors of driving cessation over a 3-year period. The final model indicated four significant risk factors for driving cessation: older age (hazard ratio [HR] = 1.06, p = .009), poorer balance as measured by the Turn 360 degrees test (HR = 1.17, p = .002), slower cognitive speed of processing as measured by the Useful Field of View test (HR = 1.37, p = .004), and poorer instrumental functional performance as assessed by the Everyday Problems Test (HR = 1.59, p < .001).

IMPLICATIONS: Although vision, health, and physical abilities are commonly considered when determining driving capacity, cognitive speed of processing and instrumental functional performance may be better indicators of subsequent likelihood of driving cessation across 3 years among older adults. Poor health and vision may only impact driving cessation to the extent that cognitive speed of processing and instrumental functioning are affected.