Making the evidence work for your patients and their families
Southampton Neurorehabilitation Conference edition:1 location:Southampton date:04-05 September 2008
Predictors of fitness to drive in people with Parkinson’s disease
Hannes Devos,1 Wim Vandenberghe,2 Alice Nieuwboer,1 Mark Tant,3 Willy De Weerdt1
1 Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium
2 Department of Neurology, University Hospital Gasthuisberg, Leuven, Belgium
3 CARA, Belgian Road Safety Institute, Brussels, Belgium
BACKGROUND: Physicians overestimate the driving ability of patients with Parkinson’s disease (PD).
AIM: To develop a short screening battery to assist physicians in the assessment of fitness to drive in people with PD.
METHODS: Differences in driving performance between 40 PD subjects and 40 healthy individuals were investigated by a driving simulator. A clinical screening comprising disease duration, UPDRS motor score, contrast sensitivity (CS), and Clinical Dementia Rating (CDR) was also administered. PD drivers were also referred to the national centre for evaluation of fitness to drive (CARA) for persons with disabilities. They were categorized in (1) fit to drive without restrictions or (2) fit to drive with restrictions or unfit to drive.
RESULTS: PD patients had a significantly lower total driving simulator score, had more traffic tickets but were not involved in more accidents as compared to their healthy peers.
Twenty-nine PD (72.5%) patients were classified as ‘fit to drive without restrictions’ while 11 (27.5%) patients were judged as ‘fit to drive with restrictions (N=10) or unfit to drive (N=1)’.
Discriminant analysis revealed a predictive equation that correctly classified 36 (90%) of the 40 patients:
(CS*16.95) – (CDR*4.17) – (UPDRS motor score*0.16) – (disease duration*0.33) – 23.49
A positive score indicates that the patient can continue driving without restrictions. Patients with a negative score need to be referred to CARA.
CONCLUSIONS: A short clinical screening tool can help physicians to ascertain fitness to drive of PD patients. If the score is below zero, referral to CARA seems to be the right course of action.
The decision regarding driving cessation is often a difficult burden, for the patient and the next of kin as well as for the physician. Physicians often lack the right tools to differentiate safe from unsafe drivers with Parkinson’s disease. We therefore developed a short clinical screening battery which can be administered during the consultation routine. The battery correctly classifies 90% of drivers with Parkinson’s disease into a pass/fail category. If a driver with Parkinson’s disease obtains a negative score on the prediction equation, referral to an official driving evaluation centre seems to be indicated.