A new study, published in Neurology Journals, suggests that it is cognitive function, not age or even the first signs of Alzheimer's, that is the most important factor in determining when the elderly should stop driving.
According to Study Finds, the researchers followed 283 participants with an average age of 72 who drove at least once a week.
Over the course of almost 6 years, the team found that participants who developed cognitive impairments or performed worse on cognitive tests were more likely to stop driving than those who maintained normal cognitive function.
“Many older drivers are aware of the changes that occur as they age, including subjective cognitive decline,” says study lead author Ganesh Babulal.
StudyFinds Staff
Cognitive impairment was measured using the Clinical Dementia Rating (CDR) scale, which ranges from normal cognitive function to severe dementia.
The researchers found that even a slight rise on this scale made participants 3.5 times more likely to decide to stop driving, compared to those who remained at zero.
In addition, the study used a more sensitive measure, called the Preclinical Alzheimer's Cognitive Composite (PACC), designed to detect cognitive changes in people who still score poorly on the CDR.
Lower PACC scores were associated with a 30% increase in the likelihood of quitting driving.
The presence of Alzheimer's disease biomarkers in the brain and cerebrospinal fluid did not predict the decision to stop driving, and suggests that the earliest stages of cognitive decline, before the disease has fully developed, can affect driving ability.
The team found that women were four times more likely to stop driving during the study than men, even after adjusting for other factors such as cognitive function.
“What we have shown in previous work is that women are often more aware of their abilities, are more willing to admit that they are no longer able to drive safely and plan the transition to quitting driving further in advance, compared to men,” concludes Babulal.
The decision to stop driving can be quite difficult. However, driving with impaired cognitive function poses numerous risks, both for the drivers themselves and for other road users.
