In the United States, licensed drivers over the age of 65 years today number more than 20 million — a figure that will increase substantially over the next few decades. Certain age-associated conditions such as dementia will lessen the expected increase, since, for reasons of safety, the people affected require earlier retirement from driving. For those diagnosed with Alzheimer's disease, the most common cause of dementia in late life, it is not a matter of if retirement from driving will be necessary, but simply when. That "when" can be difficult to determine, however, because valid and reliable methods to assess fitness to drive are lacking and little is known about individual, family and health-related factors that motivate driving cessation in patients with dementia. Herrmann and colleagues have provided a welcome addition to the paucity of literature on this topic. They analyzed data from patients referred to subspecialists in the Canadian Outcomes Study in Dementia to determine baseline factors that predicted driving cessation in older adults with Alzheimer's disease or other dementias. The study had several strengths, including its prospective design and its use of accepted clinical diagnostic criteria and assessment tools to quantify dementia-related impairment. Their findings that dementia severity and advanced age are associated with driving cessation confirmed results from other studies. Moreover, they demonstrated that level of cognitive impairment and behaviours such as agitation, apathy and hallucinations were found to be significant specific predictors of driving cessation in patients with mild-to-moderate dementia. Interestingly, at about 2 years after inclusion in the study (and therefore 2 years or more after diagnosis), 50% of these patients with dementia were still driving. That observation suggests that even in clinical settings, driving cessation does not necessarily occur promptly. (Author/publisher)
Abstract