Environmental cueing may effect performance on a road test for drivers with dementia of the Alzheimer type

Driving and Alzheimer's dementia or mild cognitive impairment: a systematic review of the existing guidelines emphasizing on the neurologist's role

BACKGROUND

Driving is a complex task requiring the integrity and the cooperation of cognition, motor, and somatosensory skills, all of which are impacted by neurological diseases.

OBJECTIVE

Identification of neurologist's role when assessing fitness to drive of cognitively impaired individuals.

METHODS

We performed a systematic review of the guidelines/recommendations (G/Rs) regarding the evaluation of driving fitness of patients with mild cognitive impairment (MCI) and/or dementia. Emphasis was put on the neurological and neuropsychological aspects of the evaluation.

RESULTS

Eighteen G/Rs were included in the review (9 national guidelines, 5 recommendation papers, 3 consensus statements, and 1 position paper). All G/Rs referred to drivers with dementia and 9/18 referred to drivers with MCI. A common approach among G/Rs is the initial trichotomization of patients in safe to drive, unsafe to drive, and undetermined cases, which are referred to a second-line evaluator. First-line evaluators are general practitioners in 10/18 G/Rs; second-line evaluators are neurologists in 7/18 G/Rs. Specific neuropsychological tests are proposed in 11/18 G/Rs and relative cut-off values in 7/18. The most commonly used tests are the MMSE, TMT, and CDT. A thorough neurological examination is proposed in only 1/18 G/R.

CONCLUSION

Although extensive multi-disciplinary research has provided useful information for driving behavior of cognitively impaired individuals, we are still far from a widely accepted approach of driving ability evaluation in this increasing population. A comprehensive assessment from a multi-disciplinary team in which the neurologist plays a critical role seems to be required, although this has not yet been implemented in any G/Rs.

Detection of Risky Driving Behaviors in the Naturalistic Environment in Healthy Older Adults and Mild Alzheimer's Disease

Analyzing naturalistic driving behavior recorded with in-car cameras is an ecologically valid method for measuring driving errors, but it is time intensive and not easily applied on a large scale. This study validated a semi-automated, computerized method using archival naturalistic driving data collected for drivers with mild Alzheimer’s disease (AD; n = 44) and age-matched healthy controls (HC; n = 16). The computerized method flagged driving situations where safety concerns are most likely to occur (i.e., rapid stops, lane deviations, turns, and intersections). These driving epochs were manually reviewed and rated for error type and severity, if present. Ratings were made with a standardized scoring system adapted from DriveCam^®. The top eight error types were applied as features to train a logistic model tree classifier to predict diagnostic group. The sensitivity and specificity were compared among the event-based method, on-road test, and composite ratings of two weeks of recorded driving. The logistic model derived from the event-based method had the best overall accuracy (91.7%) and sensitivity (97.7%) and high specificity (75.0%) compared to the other methods. Review of driving situations where risk is highest appears to be a sensitive data reduction method for detecting cognitive impairment associated driving behaviors and may be a more cost-effective method for analyzing large volumes of naturalistic data.

Driving with a neurodegenerative disorder: an overview of the current literature

Driving is important for employment, social activities, and for the feeling of independence. The decision to cease driving affects the quality of life and has been associated with reduced mobility, social isolation, and sadness. Patients with neurodegenerative disorders can experience difficulties while driving due to their cognitive, motor, and behavioral impairments. The aim of this review is to summarize the available literature on changes in driving competence and behavior in patients with neurodegenerative disorders, with a particular focus on Huntington's (HD), Parkinson's (PD), and Alzheimer's disease (AD). A systematic literature search was conducted in the PubMed/Medline database. Studies using on-road or simulated driving assessments were examined in this review. In addition, studies investigating the association between cognitive functioning and driving were included. The review identified 70 studies. Only a few publications were available on HD (n = 7) compared to PD (n = 32) and AD (n = 31). This review revealed that driving is impaired in patients with neurodegenerative disorders on all levels of driving competence. The errors most commonly committed were on the tactical level including lane maintenance and lane changing. Deficits in executive functioning, attention, and visuospatial abilities can partially predict driving competence, and the performance on neuropsychological tests might be useful when discussing potential driving cessation. Currently, there is no gold standard to assess driving ability using clinical measures such as neuropsychological assessments, so more studies are necessary to detect valid screening tools and develop useful and reliable evidence-based guidelines.

On-road Driving Performance of Patients With Bilateral Moderate and Advanced Glaucoma

PURPOSE

To compare on-road driving performance of patients with moderate or advanced glaucoma to controls and evaluate factors associated with unsafe driving.

DESIGN

Case-control pilot study.

METHODS

A consecutive sample of 21 patients with bilateral moderate or advanced glaucoma from Washington University, St Louis, Missouri and 38 community-dwelling controls were enrolled. Participants, aged 55-90 years, underwent a comprehensive clinical evaluation by a trained occupational therapist and an on-road driving evaluation by a masked driver rehabilitation specialist. Overall driving performance of pass vs marginal/fail and number of wheel and/or brake interventions were recorded.

RESULTS

Fifty-two percent of glaucoma participants scored a marginal/fail compared to 21% of controls (odds ratio [OR], 4.1; 95% CI, 1.30-13.14; P = .02). Glaucoma participants had a higher risk of wheel interventions than controls (OR, 4.67; 95% CI, 1.03-21.17; P = .046). There were no differences detected between glaucoma participants who scored a pass vs marginal/fail for visual field mean deviation of the better (P = .62) or worse (P = .88) eye, binocular distance (P = .15) or near (P = .23) visual acuity, contrast sensitivity (P = .28), or glare (P = .88). However, glaucoma participants with a marginal/fail score performed worse on Trail Making Tests A (P = .03) and B (P = .05), right-sided Jamar grip strength (P = .02), Rapid Pace Walk (P = .03), Braking Response Time (P = .03), and identifying traffic signs (P = .05).

CONCLUSIONS

Patients with bilateral moderate or advanced glaucoma are at risk for unsafe driving-particularly those with impairments on psychometric and mobility tests. A comprehensive clinical assessment and on-road driving evaluation is recommended to effectively evaluate driving safety of these patients.

Comparing caregiver and clinician predictions of fitness to drive in people with Alzheimer's disease

This observational study investigated family caregiver and clinician ratings of 75 drivers with Alzheimer's disease against scores on a standardized road test and a naturalistic driving evaluation. Clinician ratings by a physician specialized in dementia were significantly associated with road test error scores (r=.25, p=.03) but not naturalistic driving errors or global ratings of road test and naturalistic driving performance. Caregiver ratings were unrelated to either driving assessment, with two exceptions; adult child ratings of driving ability were correlated with road test error scores (r=.43, p=.02), and spousal ratings were inversely correlated with global ratings. Clinician ratings of driving competence were modestly correlated with road test performance, but caregiver ratings were more complex. Adult children may be more accurate reporters of driving ability than spouses, possibly because of less personal bias, but the reasons behind this discrepancy need further investigation.

Obstacle avoidance, visual detection performance, and eye-scanning behavior of glaucoma patients in a driving simulator: a preliminary study

The objective of this study was to evaluate differences in driving performance, visual detection performance, and eye-scanning behavior between glaucoma patients and control participants without glaucoma. Glaucoma patients (n = 23) and control participants (n = 12) completed four 5-min driving sessions in a simulator. The participants were instructed to maintain the car in the right lane of a two-lane highway while their speed was automatically maintained at 100 km/h. Additional tasks per session were: Session 1: none, Session 2: verbalization of projected letters, Session 3: avoidance of static obstacles, and Session 4: combined letter verbalization and avoidance of static obstacles. Eye-scanning behavior was recorded with an eye-tracker. Results showed no statistically significant differences between patients and control participants for lane keeping, obstacle avoidance, and eye-scanning behavior. Steering activity, number of missed letters, and letter reaction time were significantly higher for glaucoma patients than for control participants. In conclusion, glaucoma patients were able to avoid objects and maintain a nominal lane keeping performance, but applied more steering input than control participants, and were more likely than control participants to miss peripherally projected stimuli. The eye-tracking results suggest that glaucoma patients did not use extra visual search to compensate for their visual field loss. Limitations of the study, such as small sample size, are discussed.

Road test and naturalistic driving performance in healthy and cognitively impaired older adults: does environment matter?

OBJECTIVES

To relate the standardized road test to video recordings of naturalistic driving in older adults with a range of cognitive impairment.

DESIGN

Cross-sectional observational study.

SETTING

Academic medical center memory disorders clinic.

PARTICIPANTS

One hundred three older drivers (44 healthy, 59 with cognitive impairment) who passed a road test.

MEASUREMENTS

Error rate and global ratings of safety (pass with and without recommendations, marginal with restrictions or training, or fail) made by a professional driving instructor.

RESULTS

There was fair agreement between global ratings on the road test and naturalistic driving. More errors were detected in the naturalistic environment, but this did not affect global ratings. Error scores between settings were significantly correlated, and the types of errors made were similar. History of crashes corrected for miles driven per week was related to road test error scores but not naturalistic driving error scores. Global cognition (Mini-Mental State Examination) was correlated with road test and naturalistic driving errors. In healthy older adults, younger age was correlated with fewer errors on the road test and more errors in naturalistic driving.

CONCLUSION

Road test performance is a reasonable proxy for estimating fitness to drive in older individuals' typical driving environments, but differences between performance assessed using these two methods remain poorly understood and deserve further study.

Naturalistic validation of an on-road driving test of older drivers

OBJECTIVE

The objective was to compare a standardized road test to naturalistic driving by older people who may have cognitive impairment to define improvements that could potentially enhance the validity of road testing in this population.

BACKGROUND

Road testing has been widely adapted as a tool to assess driving competence of older people who may be at risk for unsafe driving because of dementia; however, the validity of this approach has not been rigorously evaluated.

METHOD

For 2 weeks, 80 older drivers (38 healthy elders and 42 with cognitive impairment) who passed a standardized road test were video recorded in their own vehicles. Using a standardized rating scale, 4 hr of video was rated by a driving instructor. The authors examine weighting of individual road test items to form global impressions and to compare road test and naturalistic driving using factor analyses of these two assessments.

RESULTS

The road test score was unidimensional, reflecting a major factor related to awareness of signage and traffic behavior. Naturalistic driving reflected two factors related to lane keeping as well as traffic behavior.

CONCLUSION

Maintenance of proper lane is an important dimension of driving safety that appears to be relatively underemphasized during the highly supervised procedures of the standardized road test.

APPLICATION

Road testing in this population could be improved by standardized designs that emphasize lane keeping and that include self-directed driving. Additional information should be sought from observers in the community as well as crash evidence when advising older drivers who may be cognitively impaired.

Assessment Tools for Evaluating Fitness to Drive: A Critical Appraisal of Evidence

Background. Many office-based assessment tools are used by occupational therapists to predict fitness to drive. Purpose. To appraise psychometric properties of such tools, specifically predictive validity for on-road performance. Methods. A literature search was conducted to identify assessment tools and studies involving on-road outcomes (behind-the-wheel evaluation, crashes, traffic violations). Using a standardized appraisal process, reviewers rated each tool's psychometrric properties, including its predictive validity with on-road performance. Findings. Seventeen measures met the inclusion criteria. Evidence suggests many tools do not have cut-off scores linked with on-road outcomes, although some had stronger evidence than others. Implications. When making a determination regarding driver fitness, clinicians should consider the psychometric properties of the tool as well as existing evidence concerning its utility in predicting on-road performance. Caution is warranted in using any one office-based tool to predict driving fitness; rather, a multifactorial-based assessment approach that includes physical, cognitive, and visual-perceptual components, is recommended.

Topographical disorientation in mild cognitive impairment: a voxel-based morphometry study

Background and Purpose

To assess the neural substrates underlying topographical disorientation (TD) in patients affected by mild cognitive impairment (MCI), forty-one patients diagnosed with MCI and 24 healthy control individuals were recruited.

Methods

TD was assessed clinically in all participants. Neurological and neuropsychological evaluations and a volumetric-head magnetic resonance imaging scan were performed in each participant. Voxel-based morphometry was used to compare patterns of gray-matter atrophy between patients with and without TD, and a group of normal controls.

Results

We found TD in 17 out of the 41 MCI patients (41.4%). The functional abilities were significantly impaired in MCI patients with TD compared to in MCI patients without TD. Voxel-based morphometry analyses showed that the presence of TD in MCI patients is associated with loss of gray matter in the medial temporal regions, including the hippocampus and parahippocampal cortex, the fusiform gyrus, the inferior occipital gyrus, the amygdala, and the cerebellum.

Conclusions

The findings found in this study represent the first evidence that the presence of TD in patients with MCI is associated with loss of gray matter in those brain regions that have been documented to be responsible for orientation in both neuropsychological and neuroimaging studies.

Practice parameter update: evaluation and management of driving risk in dementia: report of the Quality Standards Subcommittee of the American Academy of Neurology

OBJECTIVE

To review the evidence regarding the usefulness of patient demographic characteristics, driving history, and cognitive testing in predicting driving capability among patients with dementia and to determine the efficacy of driving risk reduction strategies.

METHODS

Systematic review of the literature using the American Academy of Neurology's evidence-based methods.

RECOMMENDATIONS

For patients with dementia, consider the following characteristics useful for identifying patients at increased risk for unsafe driving: the Clinical Dementia Rating scale (Level A), a caregiver's rating of a patient's driving ability as marginal or unsafe (Level B), a history of crashes or traffic citations (Level C), reduced driving mileage or self-reported situational avoidance (Level C), Mini-Mental State Examination scores of 24 or less (Level C), and aggressive or impulsive personality characteristics (Level C). Consider the following characteristics not useful for identifying patients at increased risk for unsafe driving: a patient's self-rating of safe driving ability (Level A) and lack of situational avoidance (Level C). There is insufficient evidence to support or refute the benefit of neuropsychological testing, after controlling for the presence and severity of dementia, or interventional strategies for drivers with dementia (Level U).

How does dementia affect driving in older patients?

Driving is a complex activity that always becomes impaired at some point in older adults with degenerative dementia. Over time, disruption of the visual processing circuits of the brain that link the occipital and prefrontal regions, particularly in the right hemisphere, leads to increasing degrees of driving impairment that ultimately preclude safe driving. Neuropsychological tests of visuospatial ability, executive function and attention that tap into the integrity of these brain regions provide the clinician with important information regarding the need for a formal determination of driving competence. Enhancement of cognitive function in these domains through anti-dementia therapy and exercise may partially mitigate risk; however, all drivers with dementia must ultimately retire from driving when dementia becomes moderately severe, and often in earlier stages of the illness. Future efforts to improve screening tests for hazardous driving and to develop interventions to help prolong the time that drivers with mild dementia can continue to drive safely are needed for our increasingly aged and mobile population.

At the crossroads: development and evaluation of a dementia caregiver group intervention to assist in driving cessation

Deciding when an individual with dementia must reduce or stop driving can be a stressful issue for family caregivers. The purpose of this study was to develop a group intervention to assist these caregivers with driving issues and to provide a preliminary evaluation of the comparative effectiveness of this At the Crossroads intervention. Participants were randomized to one of three arms: (1) active intervention (four 2-hour manualized educational/support group meetings; n = 31); (2) written materials only (participants received written materials after a pretest; n = 23); and (3)control (participants received written materials after a posttest; n = 12).Participants were administered a battery of self-report and interview-based questionnaires at baseline and again 2 months later. At follow-up, the active intervention group scored significantly better than both other groups on key outcome variables, including self-efficacy, communication, and preparedness. The At the Crossroads caregiver intervention appears to effectively provide education and support needed for caregivers to address driving-related issues with their loved ones.

Driving and dementia in older adults: Implementation and evaluation of a continuing education project

PURPOSE

We aimed to develop and evaluate a multimedia workshop curriculum to educate physicians and other health professionals about (a) driving-related assessment in older adults with dementia, and (b) strategies to encourage driving retirement for impaired individuals.

DESIGN AND METHODS

A curriculum developed by the Older Drivers Project of the American Medical Association was expanded for presentation by a multidisciplinary team. One pilot and seven test workshops were offered. A program evaluation method-testing knowledge, confidence, attitudes, and practice behaviors-was employed at four points in time: T1 (Time 1; pretest focusing on the previous 12 months), T2 (Time 2; same-day post-test), T3 (Time 3; post-test at 3 months), and T4 (Time 4; post-test at 12 months).

RESULTS

At T1, participants (N = 147) expressed high agreement that an assessment of driving ability is an important issue in clinical dementia care, but they reported low knowledge of assessment strategies, resources, and state reporting requirements. Modest gains in knowledge and confidence were demonstrated at both T3 (n = 93) and T4 (n = 63). In addition, the frequency of driving-related practice behaviors (i.e., incorporation of driving-related questions into clinical evaluation, chart documentation, reporting of impaired drivers) had increased significantly by T3 and T4.

IMPLICATIONS

The results indicate that a focused workshop curriculum, with practical and immediate applications to care, can motivate measurable changes in clinical practice. Once they are informed, health professionals can address issues of driving ability in older patients with dementia and, with the support of available resources, encourage impaired individuals to retire from driving for the safety of everyone on the road.

The older driver with dementia: an updated literature review

INTRODUCTION

At some point during their illness, drivers with dementia pose a public safety risk.

METHOD

To address the issue of determining driving competence in drivers with dementia, the authors reviewed 11 studies.

RESULTS

When comparing different driving assessments, the authors found that while road tests, simulators, and neuropsychological tests are important, each has limitations.

CONCLUSION

Neuropsychological tests that highlighted visual spatial skills, attention, and reaction time provided the most meaningful correlations with driving performance. Furthermore, the authors recommend that patients with MMSE scores of 24 or less have a driving evaluation, and that driving evaluations be repeated at six month intervals or more frequently if a noticeable decline is observed.

IMPACT

Because many older adults with dementia continue to drive, competence must be addressed.

Motor vehicle crashes and abnormal driving behaviours in patients with dementia in Mendoza, Argentina

Studies conducted in industrialized countries have shown that elderly demented subjects have increased risk of car accidents. However, there is no information about the effect of dementia on driving habits in non-industrialized countries. The number of motor vehicle crashes (MVC) and abnormal driving behaviours (ADB) (e.g. not recognizing traffic lights, driving in the middle of the road, etc.) were assessed with a semi-structured interview in 56 demented subjects and 31 elderly controls, all of whom were active drivers, at the Regional Registry of Dementia in Mendoza. Detailed neurological, psychiatric and neuropsychological examinations were also conducted on each subject. The presence of dementia and sex (male) predicted ADB, MVC and number of MVC (two or more). Among demented patients, ADB and MVC were associated with sex (male) and number of MVC was associated with sex (male) and Blessed Dementia Rating Scale for activities of daily living scores. Neither ADB, MCV, or number of MVC were associated with education level, or with cognitive or psychiatric measures. These findings showed that in developing countries, dementia has a significant contribution to MVC and ADB, as occurs in industrialized nations. Consequently, legislation to curb the risk of accidents caused by demented patients should be implemented. Furthermore, physicians must encourage demented patients (or their families) to discontinue driving, even those with mild dementia syndrome.