A software known as “DriveSafe DriveAware” can help evaluate if patients with Huntington’s disease still have the cognitive fitness needed to safely drive a car, a pilot study shows.
However, to increase the accuracy of the software some improvements should be made to better fit the profile of patients with Huntington’s, researchers suggest.
The study, “Cognitive Fitness to Drive in Huntington’s Disease: Assessing the Clinical Utility of DriveSafe DriveAware,” was published at the Journal of Huntington’s Disease.
Cognitive decline is a common manifestation of Huntington’s disease, along with motor and emotional function impairment. These symptoms can be a critical complication in carrying out daily life tasks, including driving.
Driving is a complex and cognitively demanding activity that requires the combination of several cognitive abilities such as attention, processing speed, planning, and visual perception skills, all of which are affected often in Huntington’s.
Patients with Huntington’s disease are required to undergo routine assessments to evaluate if they are still fit to drive. These commonly include a comprehensive occupational therapy-facilitated driving test that includes both off-road and on-road components. However, these assessments are very expensive and time-consuming.
The use of neuropsychological tests and driving simulators also have been suggested as viable assessment tools, but they have limitations, including poor accuracy to evaluate on-road response, and are still associated with high costs.
“Software programs that include real-world driving stimuli and capture the cognitive demands of driving may be a useful alternative to driving simulators, and in the clinical context, may provide a more suitable, lower cost option for evaluating the need for an onroad driving assessment,” the researchers wrote.
Australian researchers decided to evaluate the potential use of the DriveSafe DriveAware software to determine cognitive fitness for driving in Huntington’s patients.
Previous studies have demonstrated this software to be used easily to evaluate driving-related function in older people, as well as a valuable tool to evaluate cognitive fitness-to-drive in people with cognitive impairments.
The DriveSafe component assesses one’s ability to visually scan and anticipate the movements of vehicles and pedestrians in their surroundings, while the DriveAware component evaluates self-awareness of driving ability.
To test the applicability of this software for the Huntington’s population, researchers recruited 26 Huntington’s participants. Among the participants, seven were asymptomatic. As expected, symptomatic participants had more severe disease manifestations and were more likely to be cognitively impaired than pre-symptomatic participants.
At the time of the evaluation with the DriveSafe DriveAware software, 81% of the participants were still active drivers. Those who were no longer driving had stopped between one to 18 months before the study.
Eighteen of the 26 participants were found ‘‘likely to pass on-road assessment’ with the DriveSafe DriveAware software, three were “likely to fail on-road assessment” and three had inconclusive predictions and were assigned to the category of “need further testing.”
Poorer results on the DriveSafe component were significantly associated with worse motor function and higher disease burden. Functional impairment also was associated with DriveAware scores.
DriveSafe performance was significantly correlated with most measures of neuropsychological function, including decreased sustained and divided attention, processing speed, and planning ability. In contrast, DriveAware correlated only with sustained attention.
In general, the DriveSafe DriveAware software results reflected participants’ overall status, with more severe disease being associated with worse performance. Still, some participants whose results predicted they would pass on-road testing had high rates of neuropsychological impairment.
“These preliminary pilot findings underscore the potential utility of DriveSafe DriveAware as a screening tool to identify those people with Huntington’s disease who may require further on-road driving assessment,” researchers wrote.
Nevertheless, the researchers emphasized that interpretation of the results should be done carefully, because a “pass” result may not fully define a patient’s motor and neuropsychological profile.
“Further validation with an on-road driving assessment should lend adequate support to use of DriveSafe DriveAware with the Huntington’s population,” the team concluded.