[Voluntary return of driver's license and the related activity of a neurocognitive center in Okayama prefecture].

Due to the rapid increase in traffic accidents caused by the old populations of ages 65-74 and more than 75 in Japan, the renewal of driver's licenses has become more difficult following the revision of traffic laws in March 2017. As part of the driver's license clinic at Kurashiki Heisei Hospital, the present study investigated the status of voluntary license surrender in Okayama Prefecture of Japan. From March 2017 to December 2019, the number of voluntary surrenders increased from 5,434 to 10,284 cases, or at a rate of 0.42% to 0.80%, among license holders, with the old-old accounting for 68%-77% of voluntary surrenders. The major reasons for surrender were a decline in physical ability (25%-38%), a decline in driving needs (28%-60%), and family's suggestion (14%-17%). The increase in voluntary license surrender over these 3 years was common across all municipalities within Okayama Prefecture, but the surrender rate was closely correlated with the aged-society rate for both old populations of ages 65-74 and more than 75 (r = -0.5508, **p = 0.002 and r = -0.3086, p = 0.110, respectively). The driver's license clinic at Kurashiki Heisei Hospital received 110 visits during the 3-year period, in which MCI (mild cognitive impairment) accounted for 67% of voluntary surrenders (21.8%). The present study suggests that the increase in the rate of voluntary license surrender during the 3-year period was closely related to the aged-society rate in Okayama Prefecture, and that a driver's license clinic provides a detailed dementia status among license holders who have voluntarily surrendered their license.