Aim: Cognitive impairment can negatively affect driving performance and increase the risk of driving errors, leading to vehicle crashes. We used a population-based survey to identify the prevalence of cognitive impairments in older drivers.
Methods: A total of 10,073 older adults were enrolled in the National Center for Geriatrics and Gerontology - Study of Geriatric Syndromes. We characterized general cognitive impairment using the Mini-Mental State Examination (MMSE). We also used the National Center for Geriatrics and Gerontology-Functional Assessment Tool, which includes six tasks to assess word list memory, logical memory, attention and executive function, processing speed, and visuospatial skill.
Results: Just 15% of older women with moderate cognitive decline (MMSE ≤20) drove, whereas 61% of older men with moderate cognitive decline drove. Cognitively normal participants (MMSE score 27 and over) scored significantly better on six cognitive tests compared with those with mild (MMSE score 21-26) or moderate cognitive decline, and those in the mild cognitive decline group scored significantly better on six cognitive tests than those in the moderate cognitive decline group.
Conclusion: A total of 61% of older men with moderate cognitive decline did not cease driving. These older drivers showed poor cognitive performance in multiple domains compared with those with normal and mild cognitive decline. Further studies are required to clarify the relationships between cognitive decline and car crashes in these high-risk populations.
Keywords: aging; dementia; driving; mental status examination.
© 2015 Japan Geriatrics Society.