Motor vehicle crashes and drivers with DAT

Predictors of accidents in people with mild cognitive impairment, mild dementia due to Alzheimer's disease and healthy controls in simulated driving

OBJECTIVES

To examine the driving variables that predict accident probability in mild dementia due to Alzheimer's disease (AD), mild cognitive impairment (MCI) and healthy older control drivers in simulated driving. To compare the three groups in mean performance and in frequency of scores exceeding 1.5 SD from the mean.

METHODS/DESIGN

Participants were 37 drivers with MCI, 16 drivers with AD, and 21 control drivers over the age of 52. Driving measures were derived from four rural driving conditions: moderate traffic without and with distraction and high traffic without and with distraction. The measures were z-transformed based on the performance of 90 control drivers of different ages. Two unexpected incidents occurred per condition, requiring the sudden breaking to avoid an accident.

RESULTS

Drivers with AD showed significantly lower average speed, speed variability, greater headway distance, headway variability and average reaction time (RT) than control drivers. Drivers with MCI showed significantly lower average speed, greater headway distance and average RT than control drivers in the two conditions of distraction. No differences were found in accident probability. Drivers with AD had more deviant scores than both control drivers and drivers with MCI in most comparisons. Predictors of accident probability were average RT, speed variability and lateral position variability but MCI and AD status were not significant predictors in any of the regression models.

CONCLUSIONS

Despite significant differences in performance, drivers with MCI and AD did not differ in accident probability from control drivers. An individualized approach of examining individual driving performance is recommended.

Driving Fitness in Different Forms of Dementia: An Update

BACKGROUND/OBJECTIVES

Most forms of dementia are associated with progressive cognitive and noncognitive impairments that can severely affect fitness to drive. Whether safe driving is still possible in the single case, however, is often difficult to decide and may be dependent on both severity and type of the respective dementia syndrome. Particularly in early disease stages, Alzheimer disease dementia (ADD) and different types of non-Alzheimer dementias, such as vascular dementia (VaD), frontotemporal dementia (FTD), dementia with Lewy bodies (DLB), and Parkinson disease dementia (PDD), might differentially affect fitness to drive.

DESIGN

To examine the effects of severity and type of dementia on driving fitness, we conducted a systematic review with qualitative narrative synthesis, involving different driving outcomes in different forms and stages of dementia.

SETTING

Literature research included MEDLINE and PsycINFO databases with a focus on the most relevant and recent publications on the topic.

PARTICIPANTS

The population of interest included older drivers in different stages of ADD and different forms of non-Alzheimer dementias (VaD, FTD, DLB, and PDD).

MEASUREMENTS

Narrative description of driving outcomes in the population of interest.

RESULTS

Overall, previous studies suggest that driving fitness is severely impaired in moderate and severe dementia, irrespective of the type of dementia. In milder disease stages, fitness to drive appears to be more severely impaired in non-Alzheimer dementias than in ADD, since the non-Alzheimer syndromes are not only associated with driving-relevant cognitive but noncognitive risk factors, such as behavioral or motor symptoms.

CONCLUSIONS

Based on these findings, practical recommendations are presented, including a risk evaluation for driving safety, depending on severity and type of different dementia syndromes. J Am Geriatr Soc 67:2186-2192, 2019.

Diagnosed dementia and the risk of motor vehicle crash among older drivers

Older adults are an active and growing segment of drivers in the United States. We compared the risk of motor vehicle crash among older licensed drivers diagnosed with dementia to crash risk among older licensed drivers without diagnosis of dementia. This retrospective cohort study used data from Group Health (GH), a Washington State health maintenance organization. Research participants were members of GH, aged 65-79 during the study who lived in Washington State from 1999-2009. Participant health records were linked with police-reported crash and licensure records. We estimated the risk of crash for older drivers diagnosed with dementia compared to older drivers without diagnosis of dementia using a Cox proportional hazards model with robust standard errors, accounting for recurrent events (crashes). Multivariable models were adjusted for age, sex, history of alcohol abuse or depression, comorbidities, and medications. There were 29,730 eligible individuals with an active driving license. Approximately 6% were diagnosed with dementia before or during the study. The police-reported crash rate was 14.7 per 1000 driver-years. The adjusted hazard ratio of crash among older drivers with diagnosed dementia was 0.56 (95% CI 0.33, 0.95) compared to those without diagnosed dementia. On-road and simulator-based research showed older adults with dementia demonstrated impaired driving skill and capabilities. The observed lower crash risk in our study may result from protective steps to limit driving among older adults diagnosed with dementia. Future research should examine driving risk reduction strategies at the time of dementia diagnosis and their impact on reducing crash risk.

Driving in Somerset

Aims and Methods

The number of drivers on our roads with dementia is likely to increase as the elderly population grows. We performed a retrospective analysis of patients referred to our Memory Clinic in Taunton who were still driving despite a high suspicion of dementia.

Results

Twenty per cent of the patients were still driving at the time of their assessment. Ten per cent had a diagnosis of Alzheimer's disease and 10% mild cognitive impairment. The patients and/or carers stated that the patient had not been told to stop driving and none of the referral letters documented any advice about driving.

Clinical Implications

Referrers should advise all patients with possible dementia to refrain from driving until assessment by a specialist team is completed. They should be informed of the risk of medico-legal consequences if they continue to drive.

Audit of clinicians' approach to patients' driving status in a dementia day hospital setting

Aims and Method

To examine whether driving is discussed with patients attending a specialist day hospital for dementia and whether appropriate action is taken. Patients' notes were reviewed for evidence of such discussion. A questionnaire was implemented before the audit was repeated 6 months later.

Results

During the first cycle 44 patients' notes were assessed and 38 were assessed on repeat audit. The documentation of discussions regarding driving increased from 23 to 95% of notes following implementation of the questionnaire.

Clinical Implications

By discussing driving status, important legal, insurance and safety issues can be addressed. Routine use of a simple questionnaire dramatically improved the likelihood of such discussion. These findings apply for all conditions requiring Driver and Vehicle Licensing Agency notification.

Comparison of Unsafe Driving Across Medical Conditions

OBJECTIVE

To compare risks of unsafe driving in patients with medical conditions.

METHODS

This large population-based study included all patients who were referred for a fitness-to-drive evaluation at an official driving evaluation center in 2013 and 2014. Risks of unsafe driving included physician's fitness-to-drive recommendation, comprehensive fitness-to-drive decision, motor vehicle crash history, and traffic violation history.

RESULTS

A total of 6584 patients were included in the study. Risks of unsafe driving were significantly different across medical conditions (P<.001 for all outcome measures). Patients with neurological conditions comprised the majority of the database (4837; 74%), but were not at the highest risk for unsafe driving. Patients with psychiatric conditions or substance abuse did worse on most driving safety outcomes, despite their low representation in the total sample (359 [6%] and 46 [1%], respectively).

CONCLUSION

The risk of unsafe driving varied greatly across medical conditions. Sensitization campaigns, education, and medical guidelines for physicians and driver licensing authorities are warranted to identify patients at risk, especially for those with psychiatric conditions and substance abuse problems.

Safe driving and executive functions in healthy middle-aged drivers

The introduction of the point system driver's license in several European countries could offer a valid framework for evaluating driving skills. This is the first study to use this framework to assess the functional integrity of executive functions in middle-aged drivers with full points, partial points or no points on their driver's license (N = 270). The purpose of this study is to find differences in executive functions that could be determinants in safe driving. Cognitive tests were used to assess attention processes, processing speed, planning, cognitive flexibility, and inhibitory control. Analyses for covariance (ANCOVAS) were used for group comparisons while adjusting for education level. The Bonferroni method was used for correcting for multiple comparisons. Overall, drivers with the full points on their license showed better scores than the other two groups. In particular, significant differences were found in reaction times on Simple and Conditioned Attention tasks (both p-values < 0.001) and in number of type-III errors on the Tower of Hanoi task (p = 0.026). Differences in reaction time on attention tasks could serve as neuropsychological markers for safe driving. Further analysis should be conducted in order to determine the behavioral impact of impaired executive functioning on driving ability.

Car drivers with dementia: Different complications due to different etiologies?

OBJECTIVE

Older drivers with dementia are an at-risk group for unsafe driving. However, dementia refers to various etiologies and the question is whether dementias of different etiology have similar effects on driving ability.

METHODS

The literature on the effects of dementia of various etiologies on driving ability is reviewed. Studies addressing dementia etiologies and driving were identified through PubMed, PsychINFO, and Google Scholar.

RESULTS AND CONCLUSIONS

Early symptoms and prognoses differ between dementias of different etiology. Therefore, different etiologies may represent different likelihoods with regard to fitness to drive. Moreover, dementia etiologies could indicate the type of driving problems that can be expected to occur. However, there is a great lack of data and knowledge about the effects of almost all etiologies of dementia on driving. One could hypothesize that patients with Alzheimer's disease may well suffer from strategic difficulties such as finding a route, whereas patients with frontotemporal dementia are more inclined to make tactical-level errors because of impaired hazard perception. Patients with other dementia etiologies involving motor symptoms may suffer from problems on the operational level. Still, the effects of various etiologies of dementias on driving have thus far not been studied thoroughly. For the detection of driving difficulties in patients with dementia, structured interviews with patients but also their family members appear crucial. Neuropsychological assessment could support the identification of cognitive impairments. The impact of such impairments on driving could also be investigated in a driving simulator. In a driving simulator, strengths and weaknesses in driving behavior can be observed. With this knowledge, patients can be advised appropriately about their fitness to drive and options for support in driving (e.g., compensation techniques, car adaptations). However, as long as no valid, reliable, and widely accepted test battery is available for the assessment of fitness to drive, costly on-road test rides are inevitable. The development of a fitness-to-drive test battery for patients with dementia could provide an alternative for these on-road test rides, on condition that differences between dementia etiologies are taken into consideration.

Consensus statements on occupational therapy ethics related to driving

As part of an expert panel convened to examine evidence and practice related to diverse aspects of driving evaluation and rehabilitation, consensus statements were developed on ethics. This paper provides context for the ethical obligation of practitioners to assess and make recommendations about the ability of clients to safely perform the activity of driving. It highlights key articles from the literature as well as principles from the Occupational Therapy Code of Ethics and Ethics Standards (2010). The statements support the importance of identifying impairments affecting driving, which could result in harm to the client as well as to the public. The ethical and professional obligation of practitioners to evaluate, make recommendations, and possibly report and/or refer to a driver rehabilitation specialist for further services is reinforced.

Predicting road test performance in drivers with dementia

OBJECTIVES

To develop a cognitive and functional screening battery for the on-road performance of older drivers with dementia.

DESIGN

Prospective observational study.

SETTING

On-road driving evaluation clinic at an academic rehabilitation center.

PARTICIPANTS

Ninety-nine older people with dementia (63% male, mean age 74.2 ± 9), referred by community physicians to an occupational therapy driving clinic.

MEASUREMENTS

The outcome variable was pass or fail on the modified Washington University Road Test. Predictor measures were tests of visual, motor, and cognitive functioning, selected for their empirical or conceptual relationship to the complex task of driving safely.

RESULTS

Sixty-five (65%) participants failed the on-road driving test. The best predictive model, with an overall accuracy of up to 85% when participants were blinded, included the Eight-item Informant Interview to Differentiate Aging and Dementia, Clock Drawing Test score, and time to complete the Snellgrove Maze Test or Trail Making Test Part A. Visual and motor functioning were not associated with road test failure.

CONCLUSION

A screening battery that could be performed in less than 10 minutes predicted with good accuracy failure rate for the on-road driving test in this sample of older drivers with dementia. A probability of failure calculator is provided from a logistic regression model that may be useful for clinicians in their decision to refer impaired older adults for further testing. More studies are needed in larger community-based samples, along with discussions with patients, families, and clinicians, with regard to acceptable levels of test uncertainty.

The driver with dementia: a survey of physician attitudes, knowledge, and practice

BACKGROUND

One of the most difficult issues physicians must address when caring for persons with dementia is fitness to drive. The purpose of this project was to investigate the attitudes, knowledge, and practices of physicians toward drivers with dementia.

METHODS

A questionnaire that obtained perspectives about and experiences with drivers' with dementia was mailed to physicians from North Carolina and South Carolina.

RESULTS

The sample was comprised of 239 physicians who worked with persons with dementia. Respondents who were aware of the Physician's Guide to Assessing and Counseling Older Drivers, had a strong perceived role regarding driving, were older, and believed it was important to address driving were more likely to engage in driving discussions.

CONCLUSIONS

Concerns associated with the driver with dementia have implications for not only patient care but also public safety. We recommend that all physicians be encouraged to address the issue and utilize existing educational materials.

Driving decision-making in older adults with dementia

Drivers with dementia, like most other drivers, are reluctant to relinquish their driving privileges, making discussions about driving cessation difficult and of great concern to family. To better understand how driving decisions are made 13 focus groups were held with 65 participants including current drivers with dementia, their spouses, and spouses of former drivers with dementia. Results documented the use of compensation strategies by drivers with dementia and their families to maintain safe driving behaviors given declining skills, identified a lack of planning for driving cessation even in light of expectations of cessation, confirmed a desire that driving decisions be a responsibility shared between families and professionals, and showed that diagnostic delays hamper families in making long-term plans. Given the desires and needs of drivers and their spouses, a shared, consistent, and unified approach to driving decisions between professionals and families is needed.

Effects of Alzheimer's disease and mild cognitive impairment on driving ability: a controlled clinical study by simulated driving test

OBJECTIVE

To assess the effects of Alzheimer's disease (AD) and Mild Cognitive Impairment (MCI) on simulated car driving ability.

METHODS

Twenty patients with a probable AD of mild severity (Clinical Dementia Rating, CDR = 1) were compared with 20 subjects with MCI (CD = 0.5), and a group of age-matched neurologically normal controls on a driving simulation task. Measures of driving competence included the length of run, the number of infractions (omission of stop at pedestrian crossings, speed limits violation), the number of stops at traffic lights, the mean time to collision, and the number of off-road events. Results in the driving competence measures were correlated with scores obtained from simple visual reaction times and mini-mental state examination (MMSE).

RESULTS

The patients with mild AD performed significantly worse than MCI subjects and controls on three simulated driving measures, length of run and mean time to collision (p < 0.001), and number of off-road events (p < 0.01). MCI subjects had only a significantly shorter time-to-collision than healthy controls (p < 0.001). Simple visual reaction times were significantly longer (p < 0.001) in patients with AD, compared to MCI and healthy controls, and showed a borderline significant relation (p = 0.05) with simulated driving scores. Driving performance in the three groups did not significantly correlate with MMSE score as measure of overall cognitive function.

CONCLUSIONS

Mild AD significantly impaired simulated driving fitness, while MCI limitedly affected driving performance. Unsafe driving behaviour in AD patients was not predicted by MMSE scores.

Working with cognitively impaired drivers: legal issues for mental health professionals to consider

INTRODUCTION

Mental health professionals are gatekeepers of patient confidentiality. Yet, confidentiality held too strictly, by allowing a potentially dangerous driver to assume control of a car, endangers society. Recent court cases have mandated that mental health professionals must warn those who may be potentially harmed by patients. In spite of this, disagreements linger as to whether it is the responsibility of governmental agencies or mental health professionals to decide who is unfit to operate a vehicle because of cognitive impairment.

METHODS

This article addresses the legally relevant considerations when working with cognitively compromised individuals who operate a motor vehicle. Legal issues surrounding confidentiality, patient rights, foreseeable risk, and the duty to warn and protect are presented in order to understand their relationship to recent court rulings.

IMPACT ON INDUSTRY

The impact on the mental health care industry includes not only concerns about increased insurance premiums or costs due to alleged negligence or litigation expenses secondary to failure to ensure the safety of an impaired client under their care. Mental health care providers are aware that the welfare of clients with impairment to cognitive decision making ability may require unique considerations for safety such as ensuring safe and appropriate transportation.

At-risk drivers with Alzheimer's disease: recognition, response, and referral

OBJECTIVE

This manuscript addresses the following questions for licensing authorities: 1) Are drivers with Alzheimer's disease (AD) an issue that should concern licensing authorities? 2) What critical driving skills impacted by AD should authorities recognize? 3) What should their response be? 4) Do licensing authorities have a role in providing information about or referral to community agencies that offer alternative transportation options and other services?

METHODS

To address issues important to licensing authorities the authors reviewed pertinent driving and dementia literature.

RESULTS

Drivers with AD have unique impairments that should be recognized and responded to early on in the disease process, with sensitivity and respect for continued mobility. As the disease progresses and they must stop driving, former drivers and their families could benefit from resource referrals that provide information about transportation alternatives and support services in their communities.

CONCLUSIONS

The authors believe that drivers with AD should be a concern for licensing authorities. Licensing decisions and policies to assess and regulate drivers are in the end made individually by each state. Policymakers will make their decisions based upon current research and concerns of their constituency and need to consider a seamless approach to addressing safe mobility. Licensing authorities are an important partner along with individuals, family members, health care professionals, social service providers, researchers, and policymakers in assuring public safety and individual mobility. All of the partners should confront the concern directly-none should "look the other way." The goal is to keep people driving safely for as long as possible. The responsibility is to recognize, respond, and refer when driving safely is no longer assured.

Driving and dementia in Ontario: a quantitative assessment of the problem

BACKGROUND

The population is becoming increasingly aged, and concomitantly, the prevalence of dementia is steadily rising. Persons aged 65 years and over are likely to continue driving for many years and often well into the dementia process.

METHODS

Ontario Ministry of Transportation driving data, census data, and dementia prevalence data were combined to determine the number of persons with potential dementia who are driving, both now and in about 25 years' time.

RESULTS

Actual and projected Ontario figures show that the number of senior drivers will increase markedly from just under 500,000 in 1986 to nearly 2,500,000 in 2028. Similarly, the number of drivers with dementia is also increasing. Although not all drivers with dementia are necessarily dangerous, most are estimated to continue driving well into the disease process. By combining the above-mentioned data sets, a best estimate of the number of drivers with dementia in Ontario was derived. It is estimated that this group has grown from just under 15,000 in 1986 to about 34,000 in 2000 and will number nearly 100,000 in 2028.

INTERPRETATION

Increasingly, the responsibility for identifying drivers with dementia has fallen on the health care system, a role for which it was never designed nor equipped to handle. The risks associated with the dramatically increasing number of drivers with dementia demand a psychometrically sensitive and efficient screening procedure.

The Relationship Between Neuropsychological Functioning and Driving Ability in Dementia: A Meta-Analysis

A meta-analysis of 27 primary studies was conducted to examine the relationship between neuropsychological functioning and driving ability for adults with dementia. When studies using a control group were included, the relationship between cognitive measures and on-road or non-road driving measures was significant for all reported domains; mean correlations ranged from.35 to.65. Caregiver reports of driving ability and cognitive variables were correlated significantly only on measures of mental status and visuospatial skills. When studies using a control group were excluded, moderate mean correlations were observed for visuospatial skills and on-road or non-road measures, and for mental status with non-road tests. Other effects were small or nonsignificant. Implications for basing driving recommendations on neuropsychological testing are discussed.

A continuing medical education initiative for canadian primary care physicians: the driving and dementia toolkit: a pre- and postevaluation of knowledge, confidence gained, and satisfaction

This study examined the effect of the Driving and Dementia Toolkit on physician knowledge and confidence gained and the anticipated change in patient assessment and evaluated the extent to which physicians found the material to be useful. Before receiving the driving toolkit, 301 randomly selected primary care physicians received a copy of the pretest questionnaire; 145 responded and met the eligibility criteria. This group was then sent the toolkit, a satisfaction a survey, and a posttest questionnaire. Physicians were faxed the questionnaires (with up to three reminders) and telephoned if necessary. Changes in pre- and posttest results were analyzed using the McNemar test and Wilcoxon signed rank test nonparametric procedures included in SPSS, Version 10.0, and paired-samples t test. Pre- and posttest data were available and could be matched for 86 physicians (59.3%) response. Knowledge and confidence increased significantly (P</=.05) for most of the toolkit content questions. There was also a clear intent on the part of study participants to begin including additional pertinent questions in the patient/caregivers interview when assessing a patient's fitness to drive. On a scale from 1 (low) to 10 (high), overall satisfaction with the toolkit rated an average of 8.4. Use of the toolkit resulted in a clear improvement in physicians' reported knowledge of and confidence in dealing with dementia and driving. Future applications of similar innovative continuing education models can be used for other areas such as disclosure of dementia diagnosis, capacity assessments, or end-of life issues.

The Influence of Age and Gender on the Driving Patterns of Older Adults

The purpose of this study was to investigate the influences of age and gender on the driving patterns of 300 older adults. Odds of driving less than every day increased significantly with age and female gender. However, no differences were found in the reduction of overall driving. Females were more likely than men to have stopped or reduced driving under certain adverse conditions and for elective purposes. The driving patterns of today's cohort of older females suggest that the gender gap may be narrowing. Social and cultural issues such as security, safety, and identity with driving may explain existing gender differences.

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.

Driving and dementia: a review of the literature

In North American society driving is closely linked with independence. Unfortunately, the freedom to operate a motor vehicle may be lost when an individual develops a specific medical diagnosis. The complex issue of dementia and driving safety is frequently encountered by health care professionals. Physicians are required, by law, to report any medical diagnosis such as dementia, that may affect driving safety. Physicians often refer to occupational therapists to assist them in determining if an individual's impairment significantly impacts driving safety. Unfortunately many health care professionals are not using reliable, valid and sensitive tests to determine the point at which an individual with dementia will become an unsafe driver. Through a review of the literature, the authors explore the effects of normal aging and cognitive impairment on driving safety. Specific assessment tools used to assess driving ability are examined and the role of health professionals in driver assessment is discussed. Some suggestions to improve the overall approach to evaluating driving safety are offered in the conclusion.