Alzheimer’s disease and driving: review of the literature and consensus guideline from Belgian dementia experts and the Belgian road safety institute endorsed by the Belgian Medical Association

Abstract

Alzheimer's disease (AD) is a highly prevalent condition and its prevalence is expected to further increase due to the aging of the general population. It is obvious that the diagnosis of AD has implications for driving. Finally, driving discussions are also emotionally charged because driving is associated with independence and personal identity. However, it is not clear how to implement this in clinical practice and the Belgian law on driving is rather vague in its referral to neurodegenerative brain diseases in general nor does it provide clear-cut instructions for dementia or AD compared to for example driving for patients with epilepsy and as such does not prove to be very helpful. The present article reviews what is known from both literature and existing guidelines and proposes a consensus recommendation tailored to the Belgian situation agreed by both AD experts and the Belgian Road Safety Institute endorsed by the Belgian Medical Association. It is concluded that the decision about driving fitness should be considered as a dynamic process where the driving fitness is assessed and discussed early after diagnosis and closely monitored by the treating physician. The diagnosis of AD on itself definitely does not imply the immediate and full revocation of a driving license nor does it implicate a necessary referral for a formal on-road driving assessment. There is no evidence to recommend a reduced exposure or a mandatory co-pilot. A MMSE-based framework to trichotomise AD patients as safe, indeterminate or unsafe is presented. The final decision on driving fitness can only be made after careful history taking and clinical examination, neuropsychological, functional and behavioral evaluation and, only for selected cases, a formal assessment of driving performance.

The MMSE should not be the sole indicator of fitness to drive in mild Alzheimer’s dementia

“…Patients with AD were trichotomized into three groups, i.e., unsafe, indeterminate, and safe, based on proposed MMSE cutoffs (≤ 19 and ≥ 25) [ 7 ]. The outcomes of the on-road driving assessments in these three groups were reported.…”

“…Despite the influence of AD on driving, the Belgian law on driving is rather vague in its referral to and instructions for AD, and does not implicate referral to an on-road driving assessment for all drivers with mild AD [ 7 ]. In The Netherlands, drivers who receive a diagnosis of AD have a moral obligation to report their diagnosis to the Dutch driving licence authority (CBR) [ 8 ].…”

“…Unsurprisingly, patients with AD and their family members often consult the treating physician for advice regarding driving [ 12 ], although physicians are usually not sufficiently equipped with proper tools to evaluate fitness to drive [ 6 ]. Unless available clinical tools could be used for this purpose, i.e., Versijpt and colleagues [ 7 ] recently suggested a framework using the Mini-Mental State Examination (MMSE) [ 13 ] as a starting point.…”

“…Despite this association, research has shown repeatedly that the MMSE is not a useful instrument in predicting driving performance in mixed dementia samples [ 6 , 17 , 18 ]. Recently, Versijpt and colleagues [ 7 ] proposed MMSE cutoffs to trichotomize patients with AD specifically into temporarily safe, indeterminate, and unsafe drivers. The authors emphasise that many other factors are important for driving, and a final decision on driving cessation should only be made after thorough risk assessment.…”

“…The aim of the current study is to evaluate the MMSE as a valid indicator of fitness to drive in patients with AD by taking MMSE scores and on-road driving assessments from a comprehensive fitness-to-drive assessment study [ 11 ]. MMSE cutoffs proposed by Versijpt and colleagues [ 7 ] will be used to classify patients with AD as safe or unsafe drivers. Patients with AD scoring below the lower cutoff (MMSE ≤ 19) are expected to fail the on-road driving assessment, whereas patients with AD scoring above the upper cutoff (MMSE ≥ 25) are expected to pass the on-road driving assessment.…”