Longitudinal study of self-imposed driving restrictions and deficit awareness in patients with Alzheimer disease

Abstract

Thirty-five patients with Alzheimer disease (AD), including 19 who were still driving, were evaluated for level of awareness and driving status. There was no significant correlation between driving status and Mini-Mental State Examination (MMSE) scores. Only the attention subscore of the awareness questionnaire yielded a statistically significant difference between drivers and nondrivers. Follow-up of the patients who were still driving was conducted 12-18 months later. All but 4 patients had stopped driving. Caregivers responded to a questionnaire assessing the patient's driving behaviors since the onset of AD. There was no correlation between MMSE and driving status. In 7 of 10 cases, caregivers or patients made the decision that the patient should stop driving. However, caregivers reported long periods between the caregiver's perception that the patient should stop driving and actual cessation (0.5-48 months). Results suggest that AD patients do restrict several areas of their driving voluntarily and that a failure to do so may be associated with an awareness deficit. In particular, a deficit of awareness for attention was significantly associated with an absence of restricted driving behaviors such as avoiding unfamiliar routes. Awareness of a deficit that is related to driving performance may be critical to restricted driving behavior, and this change in behavior may enable the patient to prolong his or her status as a driver.