Determinants of Performance on Specific On-Road Skills in Multiple Sclerosis

In this prospective cross-sectional study, we investigated the cognitive, visual, and motor deficits underlying poor performance during on-road driving in 102 individuals with multiple sclerosis (MS). Thirteen specific skills categorized into hierarchic clusters of operational, tactical, visuo-integrative, and mixed driving were assessed during the on-road evaluation. Stepwise regression analysis identified the off-road skills that influenced overall performance on the on-road test and in each cluster. Study results showed that visuospatial function (p=0.002), inhibition (p=0.008), binocular acuity (p=0.04), vertical visual field (p=0.02), and stereopsis (p=0.03) together accounted for the highest variance in total on-road score (R2 =0.37). Attentional shift (p=0.0004), stereopsis (p=0.007), glare recovery (p=0.047), and use of assistive devices (p=0.03) best predicted the operational cluster (R2 =0.28). Visuospatial function p=0.002), inhibition (p=0.002), reasoning (p=0.003), binocular acuity (p=0.04), and stereopsis (p=0.005) best determined the tactical cluster (R2 =0.41). The visuo-integrative model (R2 =0.12) comprised binocular acuity (p=0.007) and stereopsis (p=0.045). Inhibition (p=0.0001) and binocular acuity (p=0.001) provided the best model of the mixed cluster (R2 =0.25). These results provide more insights into the specific impairments that influence different dimensions of on-road driving and may be used as a framework for targeted driving intervention programs in MS

Exploring the cognitive workload during a visual search task in Parkinson's Disease

International Congress of Parkinson's Disease and Movement Disorders , NICE, FRANCE, 22-/09/2019 - 26/09/2019Objective: To investigate cognitive workload during a visual search task in patients with Parkinson's disease (PD). Background: Visual search is one of the most important features of human activity. Visual search may be impaired in PD, which in turn may negatively affect daily life activities, such as driving. While previous studies explored visual exploration strategies during visual search tasks, no study investigated cognitive workload during visual search in PD. Cognitive workload refers to the total amount of mental effort being used to perform a task. Methods: Twenty patients with PD (age: 69 ± 8 yo; sex (Men/Women): 16/4) and 15 controls (age: 61 ± 11 yo; sex: 8/7) performed a visual search task on a driving simulator, that provides a context similar to visual search during real-life driving. They were instructed to search for a target road sign among distractor road signs. In half of the trials, the target was present (target-present trials). Response times as well as measures of cognitive workload for correct detections trials were investigated in the two groups. Cognitive workload was measured by the Index of Cognitive Activity (ICA), which was based on the number of times per second that an abrupt discontinuity in the pupil signal was detected. To investigate the cognitive workload over time for correct detection trials in the two groups, response time values were transformed to a continuous scale of percentage completion time, ranging from 0 (start of the trial) to 100% (button press) since response times were different between participants. Results: PD patients were significantly slower than controls to respond correctly to the visual search task, particularly for target-present trials. PD patients had increased values in cognitive workload throughout the entire duration of the task when compared to baseline (p < 0.05). By contrast, few significant differences were observed in controls (at 5% and 15%). Conclusions: These findings suggest that PD patients required increased and longer effort to correctly perform the visual search task compared with baseline cognitive workload. The use of ICA in patients with PD while performing a static visual search task provides new information into the effort (cognitive workload) required by patients on a moment-to-moment basis

Comorbidities in Drivers with Parkinson Disease

Previous studies have shown that comorbidities have an impact on driving performance in older adults. No study has established the relationships between comorbidities and driving in persons with Parkinson disease (PD). The aims of this study were (1) to report the types of comorbidity in a group of 111 drivers with PD and (2) to identify whether the comorbidity associated with PD is a predictor of overall fitness-to-drive decisions, crashes, and validity duration of driving license. Results showed that 72 participants (64.9%) had only Parkinson disease, and 39 (35.1%) participants had one or more medical conditions in addition to PD. The most frequent comorbidities were visual disorders (26.4%), heart and blood disorders (16.2%), neurological disorders other than PD (11.8%), and locomotor disorders (11.8%). Contrarily to what we expected, we did not find any significant associations between comorbidities and overall fitness-to-drive decisions, car crashes, or validity duration of driving license. We conclude that in this sample of drivers with PD, comorbidity was not a significant predictor of overall fitness-to-drive decisions

Agreement Between Physician Rating and On-Road Decision for Drivers with Multiple Sclerosis

The recommendation of the referring physician is paramount in the decision making process of fitness to drive for individuals with multiple sclerosis (MS). This medical advice is carefully considered by fitness to drive officials when making a final decision. In this study, we sought to determine the reliability between physician recommendation and decision of the on-road assessor in 95 individuals with MS. The percentage agreement (po) and prevalence and bias adjusted kappa (PABAK) were used as measures of reliability. The on-road assessor found no concerns on the road in 87 (92%) of the individuals; 6 (6%) exhibited difficulties on the road that were of concern; and 2 (2%) were advised to discontinue driving based on the findings of the road test. The po between referring physician and on-road assessor was 83%. The PABAK showed a reliability coefficient of 0.76 (p \u3c 0.0001). No differences were found in po between neurologists (83%) and general practitioners (88%, Fisher’s Exact = 0.56). Binocular acuity correlated significantly with the on-road driving decision (Spearman = -0.30; p = 0.004). We conclude that, in this sample of drivers with MS, physicians were most of the time accurate in their appraisal of their patients’ driving capabilities

Effect of Cognitive Demand on Functional Visual Field Performance in Senior Drivers with Glaucoma

A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author's publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Purpose: To investigate the effect of cognitive demand on functional visual field performance in drivers with glaucoma. Method: This study included 20 drivers with open-angle glaucoma and 13 age- and sex-matched controls. Visual field performance was evaluated under different degrees of cognitive demand: a static visual field condition (C1), dynamic visual field condition (C2), and dynamic visual field condition with active driving (C3) using an interactive, desktop driving simulator. The number of correct responses (accuracy) and response times on the visual field task were compared between groups and between conditions using Kruskal–Wallis tests. General linear models were employed to compare cognitive workload, recorded in real-time through pupillometry, between groups and conditions. Results: Adding cognitive demand (C2 and C3) to the static visual field test (C1) adversely affected accuracy and response times, in both groups (p < 0.05). However, drivers with glaucoma performed worse than did control drivers when the static condition changed to a dynamic condition [C2 vs. C1 accuracy; glaucoma: median difference (Q1–Q3) 3 (2–6.50) vs. controls: 2 (0.50–2.50); p = 0.05] and to a dynamic condition with active driving [C3 vs. C1 accuracy; glaucoma: 2 (2–6) vs. controls: 1 (0.50–2); p = 0.02]. Overall, drivers with glaucoma exhibited greater cognitive workload than controls (p = 0.02). Conclusion: Cognitive demand disproportionately affects functional visual field performance in drivers with glaucoma. Our results may inform the development of a performance-based visual field test for drivers with glaucoma

Normative Values for Driving Simulation Parameters: A Pilot Study

In this pilot study, data obtained from a population of healthy younger (18-24 yrs), middle aged (25-64 yrs) and older drivers (65+ yrs) were used to establish normative values of parameters commonly documented during simulated driving. The older drivers’ performances in most of the driving skills assessed were significantly worse than those of the other 2 classes of drivers. In line with previous studies, our data showed deterioration of driving skills with increasing age. The test-retest reliability of the driving simulation parameters were moderate to very high

Reliability of a Road Test After Stroke

Background: Despite physical, perceptual and cognitive impairments, amongst others, which might affect driving after stroke, some patients have demonstrated the ability to resume safe driving. Such patients are identified following strictly administered predriving evaluations. The road test is generally acclaimed to be the most valid test of driving performance. Aim: The purpose of this study was to determine the reliability of the road test when performed by stroke patients in Belgium. Method: This was a prospective study of a predriving evaluation at the Belgian Road Safety Institute. Thirty subjects with sequelae of stroke were included. Subjects were accompanied and evaluated during the road test by one of two assessors (A or B) from the road safety institute in an automatic car fitted with a video camera for recording driving performance. Inter-rater reliability was evaluated by comparing results from (1) real-life performance and video recording and (2) between-video judgements. Results: Most sub-items of the road test showed \u3e80% scoring agreement between the various evaluations. Intraclass correlation coefficient (ICC) of the items varied from -0.08 to 1.0. ICC of the overall performance was 0.62 when real-life scores were compared with video evaluations and 0.80 in video versus video comparison. Conclusion: Driving is important for optimal participation in daily and social activities. The reliability of assessing overall performance of the on-road test is moderately high and better when assessed using same evidence. Yet, the reliability of some items needs further attention

Determinants of Driving After Stroke

Objective: To identify from a predriving assessment the tests that best predict the driving ability of stroke patients. Design: Examination of records of 104 first ever stroke patients who visited the Belgian Institute for Road Safety in 1998 and 1999 and performed the medical, visual, perceptual and the ‘on the road’ assessments. Measures: Variables such as age, sex, side of lesion, driving experience, visual tests, neuropsychological assessments most of which are from the Test for Attentional Performance (TAP) battery and an ‘on the road’ test were considered. Based on performances of subjects on the tests, a suitable, not immediately suitable or not suitable to drive decision was jointly taken by the team of assessors. Results: Following a logistic regression analysis, a combination of side of lesion, kinetic vision, visual scanning and the ‘on the road’ tests led to the best model in predicting the final group decision (R2 =0.53). The ‘on the road’ test was the most important determinant (R2 =0.42). Conclusion: The predictive accuracy of the decision is moderate. Inclusion of assessments more closely related to real road situations should be considered

Effect of Simulator Training on Driving After Stroke: A Randomized Controlled Trial

Neurologically impaired persons seem to benefit from drivingtraining programs, but there is no convincing evidence to support this notion. Wetherefore investigated the effect of simulator-based training on driving afterstroke. Eighty-three first ever sub-acute stroke patients entered a 5-week, 15-hourtraining program in which they were randomly allocated to either an experimental(simulator-based training) or control (driving-related cognitive tasks) group.Performance in off-road evaluations and an on-road test were used to assess thedriving ability of subjects pre- and post-training. Outcome of an official predrivingassessment administered 6 to 9 months post stroke were also considered.Both groups significantly improved in a visual and many neuropsychologicalevaluations and in the on-road test after training. There were no significantdifferences between both groups in improvements from pre- to post-trainingexcept in the “road sign recognition test,” in which the experimental subjectsimproved more. Statistically significant improvements in the three-class decision(“fit to drive,” “temporarily unfit to drive” and “unfit to drive”) were found infavor of the experimental group. Academic qualification and overall disabilitytogether determined subjects who benefited most from the simulator-baseddriving training. Significantly more experimental subjects (73%) than controls(42%) passed the follow-up official pre-driving assessment and were legallyallowed to resume driving. We concluded that simulator-based driving trainingwas a better method, especially for well educated and less disabled stroke patients. However, the findings of the study may have been modified as a resultof the large number of dropouts and the possibility of some neurological recoveryunrelated to training