Fitness to drive in older persons with cognitive impairments

In our aging society, the segment of elderly with functional disorders will
grow in the population of road users. Being able to drive is very important for
the independence and wellbeing of elderly. However, disorders and illness can
affect the fitness to drive negatively. Especially for cognitive disorders like
dementia it is unclear when to draw the line and how the fitness to drive can
be determined. The *Regeling eisen geschiktheid 2000* from the Dutch Ministry
of Infrastructure and Environment contains the Dutch regulations about these
criteria. However, at the moment the formal criteria are merely described,
without specifying the assessment methods.

The most important objective of this study is the validation of various
examination procedure to assess fitness to drive in older persons with
cognitive impairments. The assessment procedure comprises nosological dementia
diagnoses (e.g. AD, FTD) , profile and severity of the cognitive impairments
(CDR) , biographical data and driving experience, dedicated
neuropsychological and visual tests and test-drives in a driving simulator and
on-road. We will investigate the mutual relations between these various
domains . An essential part of the study is the on-road test of the CBR
(practical fitness to drive) which is the Dutch 'golden standard' for
determining fitness to drive in the case of cognitive impairment.
For the neuropsychological tests and the simulator driving test, normative data
will be collected and we will form and test models to predict practical
fitness to drive from combinations of data in the various domains.
Specifically, we expect that the relationship between neuropsychological test
results and practical fitness to drive depends on the nosological dementia
diagnosis and the profile of dementia.
Based on the knowledge we will gather during the study, we will improve tje
procedure of testing the fitness to drive of people with mild or very mild
dementia. This will result in less burden and costs for the patients and
organizations involved.

All participants will follow the same procedure:
Fill out a questionnaire (about the driving behavior of the participant)
Interviews of patients and partners (CDR and MMSE, driving
experience,education)
Neuropsychological examination (neuropsychological tests of visual,
visual-motor and cognitive functions important for driving)
Driving simulator (to provide performance based measures of practical fitness
to drive)
On-road driving test (the Dutch golden standard, a subjective evaluation of
practical fitness to drive)
Feedback on the results and advice
Follow up via phone

The participants will be attending the researchcenter once for the NPO and the
tests in the driving simulator. This takes about 3,5 hours to complete. Breaks
will be added if necessary. On a seperate day, an appointment will be made
with the CBR for the on road driving test. The on road driving test takes one
hour of the participants time. Participants will receive feedback on the
results and an advice based on these results. After 3 to 4 months, they will
receive a phonecall from the researcher with questions about whether they
ceased driving and there general health.

Persons with MCI or (very) mild dementia (CDR 0.5 en CDR 1) will generally be
asked to participate shortly after having received the diagnosis.
Participation has the advantage of having a comprehensive driving evaluation
without direct consequences for their driving license, including an on road
test by the CBR. However, the results of the on-road test can labeled as
official if a subject asks for it. This could occur in case he/she performed
adequately on the on-road test; in that case the license will be renewed for
1-3 years. In case the subject failed the on-road test, he or she will,
depending on the performance, be advised to take driving lessons and have an
official examination afterwards, or to stop driving and handing in the license.
This advice will not be reported to the CBR however.
Besides, persons with CDR=0.5 and a positive result in the on-road test,
have the advantage that the neuropsychological assessment which is essential
for an extension of the driving license longer than a year is without costs
for them. In all cases the results of the examination will be discussed with
the subjects and families.

While driving the driving simulator it is possible that the participant will
get 'simulator sickness'. We will inform the participant beforehand that this
is possible. During the driving simulator tests, the physical wellbeing of the
participants is being monitored carefully. If the participant is not feeling
well, the simulator is stopped immediately. The driving simulator-part of the
study will be terminated for this participant. When the participant is feeling
well enough to go home, he/she is allowed to do so.