There are few studies about driving and dementia in Korea. The purpose of this study is to investigate the real condition of automobile driving in patients with dementia and the characteristics of those who continue to drive after diagnosis of dementia.

A total of 4,377 patients including 3,792 with Alzheimer's disease and 585 with vascular dementia were recruited from multiple nationwide hospitals. Clinical evaluations and neuropsychological tests were done in them according to the protocol of the Clinical Research Center for Dementia of South Korea study. Caregivers replied which patients drove an automobile, gave up driving, or has never driven. The same evaluations of them were followed after one year.

There were 272 (6.2%) drivers, 321 (7.3%) ex-drivers, and 3,784 (86.5%) non-drivers with dementia. Drivers with dementia were younger and had higher Korean Mini-Mental State Examination (K-MMSE) (21.5±4.3 vs 19.8±5.1 vs 17.4±5.2, p <0.001) and lower Clinical Dementia Rating scale-Sum of Boxes (CDR-SB) scores (4.08±2.15 vs 5.80±3.41 vs 5.83±3.39, p <0.001) compared with ex-drivers and non-drivers with dementia. The drivers and ex-drivers with dementia had higher educational level and a higher proportion of male compared with non-drivers with dementia (77.6% vs 80.1% vs 23.3%, p <0.001). About 54.6% of the drivers with dementia continued to drive at one year after diagnosis of dementia. They had higher K-MMSE (23.2±3.6 vs 20.8±4.5, p =0.003) and lower CDR-SB scores (3.30±1.47 vs 4.40±1.85, p =0.001) at baseline compared with those who quitted driving after baseline.

Male patients who were relatively young and had high educational level and mild dementia had a tendency to drive an automobile at that time of diagnosis of dementia. About half of them continued to drive after diagnosis of dementia.