Real-life driving outcomes in Parkinson disease

Parkinson's Disease and Driving Fitness: A Systematic Review of the Existing Guidelines

BACKGROUND

Motor/nonmotor symptomatology and antiparkinsonian drugs deteriorate the driving ability of Parkinson's disease (PD) patients.

OBJECTIVES

Treating neurologists are frequently asked to evaluate driving fitness of their patients and provide evidence-based consultation. Although several guidelines have been published, the exact procedure along with the neurologist's role in this procedure remains obscure.

METHODS

We systematically reviewed the existing guidelines, regarding driving fitness evaluation of PD patients. We searched MEDLINE and Google Scholar and identified 109 articles. After specified inclusion criteria were applied, 15 articles were included (nine national guidelines, five recommendation papers, and one consensus statement).

RESULTS

The treating physician is proposed as the initial evaluator in 8 of 15 articles (neurologist in 2 articles) and may refer patients for a second-line evaluation. The evaluation should include motor, cognitive, and visual assessment (proposed in 15, 13, and 8 articles, respectively). Specific motor tests are proposed in eight articles (cutoff values in four), whereas specific neuropsychological and visual tests are proposed in seven articles each (cutoff values in four and three articles, respectively). Conditional licenses are proposed in 11 of 15 articles, to facilitate driving for PD patients. We summarized our findings on a graphic of the procedure for driving fitness evaluation of PD patients.

CONCLUSIONS

Neurological aspects of driving fitness evaluation of PD patients are recognized in most of the guidelines. Motor, neuropsychological, visual, and sleep assessment and medication review are key components. Clear-cut instructions regarding motor, neuropsychological, and visual tests and relative cutoff values are lacking. Conditional licenses and periodical reevaluation of driving fitness are important safety measures.

Does in-vehicle automation help individuals with Parkinson's disease? A preliminary analysis

Introduction

PD is a progressive neurodegenerative disorder that affects, according to the ICF, body systems (cognitive, visual, and motor), and functions (e.g., decreased executive functions, decreased visual acuity, impaired contrast sensitivity, decreased coordination)-all which impact driving performance, an instrumental activity of daily living in the domain of "Activity" and "Participation" according to the ICF. Although there is strong evidence of impaired driving performance in PD, few studies have explored the real-world benefits of in-vehicle automation technologies, such as in-vehicle information systems (IVIS) and advanced driver assistance systems (ADAS), for drivers with PD. These technologies hold potential to alleviate driving impairments, reduce errors, and improve overall performance, allowing individuals with PD to maintain their mobility and independence more safely and for longer periods. This preliminary study aimed to fill the gap in the literature by examining the impact of IVIS and ADAS on driving safety, as indicated by the number of driving errors made by people with PD in an on-road study.

Methods

Forty-five adults with diagnosed PD drove a 2019 Toyota Camry equipped with IVIS and ADAS features (Toyota Safety Sense 2.0) on a route containing highway and suburban roads. Participants drove half of the route with the IVIS and ADAS systems activated and the other half with the systems deactivated.

Results

The results suggest that systems that assume control of the driving task, such as adaptive cruise control, were most effective in reducing driving errors. Furthermore, individual differences in cognitive abilities, particularly memory, were significantly correlated with the total number of driving errors when the systems were deactivated, but no significant correlations were present when the systems were activated. Physical capability factors, such as rigidity and bradykinesia, were not significantly correlated with driving error.

Discussion

Taken together, these results show that in-vehicle driver automation systems can benefit drivers with PD and diminish the impact of individual differences in driver cognitive ability.

Real-World Driving Data Indexes Dopaminergic Treatment Effects in Parkinson's Disease

Background

Driving is a complex, everyday task that impacts patient agency, safety, mobility, social connections, and quality of life. Digital tools can provide comprehensive real-world (RW) data on driver behavior in patients with Parkinson's disease (PD), providing critical data on disease status and treatment efficacy in the patient's own environment.

Objective

This pilot study examined the use of driving data as a RW digital biomarker of PD symptom severity and dopaminergic therapy effectiveness.

Methods

Naturalistic driving data (3974 drives) were collected for 1 month from 30 idiopathic PD drivers treated with dopaminergic medications. Prescriptions data were used to calculate levodopa equivalent daily dose (LEDD). The association between LEDD and driver mobility (number of drives) was assessed across PD severity, measured by the Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS).

Results

PD drivers with worse motor symptoms based on self-report (Part II: P = 0.02) and clinical examination (Part III: P < 0.001) showed greater decrements in driver mobility. LEDD levels >400 mg/day were associated with higher driver mobility than those with worse PD symptoms (Part I: P = 0.02, Part II: P < 0.001, Part III: P < 0.001).

Conclusions

Results suggest that comprehensive RW driving data on PD patients may index disease status and treatment effectiveness to improve patient symptoms, safety, mobility, and independence. Higher dopaminergic treatment may enhance safe driver mobility in PD patients with worse symptom severity.

Prospective controlled study on the effects of deep brain stimulation on driving in Parkinson's disease

To explore the influence of bilateral subthalamic deep brain stimulation (STN-DBS) on car driving ability in patients with Parkinson's disease (PD), we prospectively examined two age-matched, actively driving PD patient groups: one group undergone DBS-surgery (PD-DBS, n = 23) and one group that was eligible for DBS but did not undergo surgery (PD-nDBS, n = 29). In PD-DBS patients, investigation at Baseline was done just prior and at Follow-up 6-12 month after DBS-surgery. In PD-nDBS patients, time interval between Baseline and Follow-up was aimed to be comparable. To assess the general PD driving level, driving was assessed once in 33 age-matched healthy controls at Baseline. As results, clinical and driving characteristics of PD-DBS, PD-nDBS and controls did not differ at Baseline. At Follow-up, PD-DBS patients drove unsafer than PD-nDBS patients. This effect was strongly driven by two single PD-DBS participants (9%) with poor Baseline and disastrous Follow-up driving performance. Retrospectively, we could not identify any of the assessed motor and non-motor clinical Baseline characteristics as predictive for this driving-deterioration at Follow-up. Excluding these two outliers, comparable driving performance between PD-DBS and PD-nDBS patients not only at Baseline but also at Follow-up was demonstrated. Age, disease duration and severity as well as Baseline driving insecurity were associated with poorer driving performance at Follow-up. This first prospective study on driving safety in PD after DBS surgery indicates that DBS usually does not alter driving safety but might increase the risk for driving deterioration, especially in single subjects with already unsafe driving prior to DBS surgery.

RCT protocol for driving performance in people with Parkinson's using autonomous in-vehicle technologies

Introduction

Driving is an essential facilitator of independence, community participation, and quality of life. Drivers with Parkinson's Disease (PD) make more driving errors and fail on-road evaluations more than healthy controls. In-vehicle technologies may mitigate PD-related driving impairments and associated driving errors. Establishing a rigorous study protocol will increase the internal validity and the transparency of the scientific work.

Methods

We present a protocol to assess the efficacy of autonomous in-vehicle technologies (Level 1) on the driving performance of drivers with PD via a randomized crossover design with random allocation. Drivers with a PD diagnosis based on established clinical criteria (N = 105), referred by neurologists, are exposed to two driving conditions (technology activated or not) on a standardized road course as they drove a 2019 Toyota Camry. The researchers collected demographic, clinical, on-road data observational and kinematic, and video data to understand several primary outcome variables, i.e., number of speeding, lane maintenance, signaling, and total driving errors.

Discussion

The protocol may enhance participant adherence, decrease attrition, provide early and accurate identification of eligible participants, ensure data integrity, and improve the study flow. One limitation is that the protocol may change due to unforeseen circumstances and assumptions upon implementation. A strength is that the protocol ensures the study team executes the planned research in a systematic and consistent way.

Following, adapting, and refining the protocol will enhance the scientific investigation to quantify the nuances of driving among those with PD in the era of automated in-vehicle technologies.

Trial registration

ClinicalTrials.gov NCT04660500.

Clinical Factors Predicting Voluntary Driving Cessation among Patients with Parkinson’s Disease

Factors that influence the decision of voluntary driving cessation in patients living with Parkinson’s disease (PD) are still unclear. We aimed to reveal the factors affecting the decision of voluntary driving cessation in patients with PD. This hospital-based cross-sectional study recruited consecutive outpatients with PD. Data on sociodemographic and clinical characteristics and medication use were collected from the patients using semistructured interviews. Cognitive function was evaluated using the Japanese version of the Montreal Cognitive Assessment (MoCA-J). We excluded patients with dementia or motor impairment ( $\text{Hoehn}-\text{Yahr}\text{stage}>3$ ). We divided the patients into two groups, with and without voluntary driving cessation (D: driver; RD: retired driver), and conducted investigations using multivariate logistic regression analyses. Of the 40 patients, 8 (20.0%) voluntarily retired from driving. Patients who decided on driving cessation had a higher prevalence of freezing of gait (FOG) (D vs. RD, 25.0% vs. 87.5%; $P=0.001$ ) and tended to have lower scores for attention in the MoCA-J (D vs. RD, $5.0\pm 1.2$ vs. $4.1\pm 1.4$ ; $P=0.086$ ). Multivariable analysis showed that FOG was independently associated with driving cessation (odds ratio: 14.46, 95% confidence interval: 1.91–303.74). FOG was associated with voluntary driving cessation in patients with PD without dementia or severe motor impairment. Physicians should consider providing extensive social support to maintain patients’ mobility and independence, especially if the patients have these clinical factors.

Driving and Parkinson's Disease: A Survey of the Patient's Perspective

BACKGROUND

Parkinson's disease (PD) is a multi-system disorder that can impact on driving ability. Little is known about how these changes in driving ability affect people with PD, making it difficult for clinicians and carers to offer appropriate support.

OBJECTIVE

To assess patient views concerning the effect of PD on their driving ability, the impact of these changes and how they manage them.

METHOD

An online survey was created by a team of clinicians, people with PD, their carers, and representatives from Parkinson's UK. People with PD throughout the United Kingdom were invited to participate through Parkinson's UK's website, newsletter and Parkinson's Excellence Network email list.

RESULTS

805 people with PD took part in the survey. We found that the loss of a driving licence had an adverse impact on employment, socialisation, travel costs and spontaneous lifestyle choices. Multiple changes in driving ability related to PD were described, including that impulse control disorders can have an adverse impact on driving. Changes in driving ability caused people to change their driving practices including taking shorter journeys and being less likely to drive at night. Participants advised managing changes in driving ability through planning, vehicle adaptions, maintaining skills and self-assessment.

CONCLUSION

This study demonstrates the impact that changes in driving ability can have on the lifestyle of people with PD and reveals the strategies that individuals adopt to manage these changes.

Vision, attention, and driving

Safe driving demands the coordination of multiple sensory and cognitive functions, such as vision and attention. Patients with neurologic or ophthalmic disease are exposed to selective pathophysiologic insults to driving-critical systems, placing them at a higher risk for unsafe driving and restricted driving privileges. Here, we evaluate how vision and attention contribute to unsafe driving across different patient populations. In ophthalmic disease, we focus on macular degeneration, glaucoma, diabetic retinopathy, and cataract; in neurologic disease, we focus on Alzheimer's disease, Parkinson's disease, and multiple sclerosis. Unsafe driving is generally associated with impaired vision and attention in ophthalmic and neurologic patients, respectively. Furthermore, patients with ophthalmic disease experience some degree of impairment in attention. Similarly, patients with neurologic disease experience some degree of impairment in vision. While numerous studies have demonstrated a relationship between impaired vision and unsafe driving in neurologic disease, there remains a dearth of knowledge regarding the relationship between impaired attention and unsafe driving in ophthalmic disease. In summary, this chapter confirms-and offers opportunities for future research into-the contribution of vision and attention to safe driving.

Approach to Cognitive Impairment in Parkinson's Disease

Cognitive dysfunction is common in Parkinson's disease (PD) and predicts poor clinical outcomes. It is associated primarily with pathologic involvement of basal forebrain cholinergic and prefrontal dopaminergic systems. Impairments in executive functions, attention, and visuospatial abilities are its hallmark features with eventual involvement of memory and other domains. Subtle symptoms in the premotor and early phases of PD progress to mild cognitive impairment (MCI) which may be present at the time of diagnosis. Eventually, a large majority of PD patients develop dementia with advancing age and longer disease duration, which is usually accompanied by immobility, hallucinations/psychosis, and dysautonomia. Dopaminergic medications and deep brain stimulation help motor dysfunction, but may have potential cognitive side effects. Central acetylcholinesterase inhibitors, and possibly memantine, provide modest and temporary symptomatic relief for dementia, although there is no evidence-based treatment for MCI. There is no proven disease-modifying treatment for cognitive impairment in PD. The symptomatic and disease-modifying role of physical exercise, cognitive training, and neuromodulation on cognitive impairment in PD is under investigation. Multidisciplinary approaches to cognitive impairment with effective treatment of comorbidities, proper rehabilitation, and maintenance of good support systems in addition to pharmaceutical treatment may improve the quality of life of the patients and caregivers.

Driving in Parkinson Disease

Driving is impaired in most patients with Parkinson disease because of motor, cognitive, and visual dysfunction. Driving impairments in Parkinson disease may increase the risk of crashes and result in early driving cessation with loss of independence. Drivers with Parkinson disease should undergo comprehensive evaluations to determine fitness to drive with periodic follow-up evaluations as needed. Research in rehabilitation of driving and automation to maintain independence of patients with Parkinson disease is in progress.

Visual Attention Cut Points for Driver Fitness in Parkinson's Disease

This study determined whether the Useful Field of View™ Risk Index (UFOV RI) adds value as a predictor of on-road outcomes in drivers with Parkinson's disease (PD) when considered with age, gender, and disease severity and compared with community-dwelling older drivers (Controls). A total of 101 PD drivers and 138 Controls underwent a comprehensive driving evaluation, including an on-road assessment. Logistic regression analyses determined the associations of age, gender, visual attention, and disease severity to on-road outcomes. Receiver operating characteristic curve analyses determined the optimal UFOV RI cut points to predict on-road outcomes. Above adding age and gender, the UFOV RI alone predicted on-road outcomes in PD, while the UFOV RI and age predicted on-road outcomes in Controls. Regardless of disease severity, visual attention was more impaired in PD than in Controls. The UFOV RI cut point of 3 provided the fewest misclassifications (n = 25) in PD. The UFOV RI is a valid screening predictor of on-road outcomes across PD drivers of different disease severity, but has moderate sensitivity and specificity.

Driving impairment and crash risk in Parkinson disease: A systematic review and meta-analysis

OBJECTIVES

To provide the best possible evidence base for guiding driving decisions in Parkinson disease (PD), we performed a meta-analysis comparing patients with PD to healthy controls (HCs) on naturalistic, on-the-road, and simulator driving outcomes.

METHODS

Seven major databases were systematically searched (to January 2018) for studies comparing patients with PD to HCs on overall driving performance, with data analyzed using random-effects meta-analysis.

RESULTS

Fifty studies comprising 5,410 participants (PD = 1,955, HC = 3,455) met eligibility criteria. Analysis found the odds of on-the-road test failure were 6.16 (95% confidence interval [CI] 3.79-10.03) times higher and the odds of simulator crashes 2.63 (95% CI 1.64-4.22) times higher for people with PD, with poorer overall driving ratings also observed (standardized mean differences from 0.50 to 0.67). However, self-reported real-life crash involvement did not differ between people with PD and HCs (odds ratio = 0.84, 95% CI 0.57-1.23, p = 0.38). Findings remained unchanged after accounting for any differences in age, sex, and driving exposure, and no moderating influence of disease severity was found.

CONCLUSIONS

Our findings provide persuasive evidence for substantive driving impairment in PD, but offer little support for mandated PD-specific relicensure based on self-reported crash data alone, and highlight the need for objective measures of crash involvement.

Longitudinal decline of driving safety in Parkinson disease

OBJECTIVE

To longitudinally assess and predict on-road driving safety in Parkinson disease (PD).

METHODS

Drivers with PD (n = 67) and healthy controls (n = 110) drove a standardized route in an instrumented vehicle and were invited to return 2 years later. A professional driving expert reviewed drive data and videos to score safety errors.

RESULTS

At baseline, drivers with PD performed worse on visual, cognitive, and motor tests, and committed more road safety errors compared to controls (median PD 38.0 vs controls 30.5; p < 0.001). A smaller proportion of drivers with PD returned for repeat testing (42.8% vs 62.7%; p < 0.01). At baseline, returnees with PD made fewer errors than nonreturnees with PD (median 34.5 vs 40.0; p < 0.05) and performed similar to control returnees (median 33). Baseline global cognitive performance of returnees with PD was better than that of nonreturnees with PD, but worse than for control returnees (p < 0.05). After 2 years, returnees with PD showed greater cognitive decline and larger increase in error counts than control returnees (median increase PD 13.5 vs controls 3.0; p < 0.001). Driving error count increase in the returnees with PD was predicted by greater error count and worse visual acuity at baseline, and by greater interval worsening of global cognition, Unified Parkinson's Disease Rating Scale activities of daily living score, executive functions, visual processing speed, and attention.

CONCLUSIONS

Despite drop out of the more impaired drivers within the PD cohort, returning drivers with PD, who drove like controls without PD at baseline, showed many more driving safety errors than controls after 2 years. Driving decline in PD was predicted by baseline driving performance and deterioration of cognitive, visual, and functional abnormalities on follow-up.

Use, maintenance and dose effects of cognitive speed of processing training in Parkinson's disease

INTRODUCTION

Recent research indicated that cognitive speed of processing training (SPT) improved Useful Field of View (UFOV) among individuals with Parkinson's disease (PD). The effects of SPT in PD have not been further examined. The objectives of the current study were to investigate use, maintenance and dose effects of SPT among individuals with PD.

METHODS

Participants who were randomized to SPT or a delayed control group completed the UFOV at a six-month follow-up visit. Use of SPT was monitored across the six-month study period. Regression explored factors affecting SPT use. Mixed effect models were conducted to examine the durability of training gains among those randomized to SPT (n = 44), and training dose effects among the entire sample (n = 87).

RESULTS

The majority of participants chose to continue to use SPT (52%). Those randomized to SPT maintained improvements in UFOV performance. A significant dose effect of SPT was evident such that more hours of training were associated with greater UFOV performance improvements. The cognitive benefits derived from SPT in PD may be maintained for up to three months.

CONCLUSION

Future research should determine how long gains endure and explore if such training gains transfer.

Predictors of Citation Rate in Psychology: Inconclusive Influence of Effect and Sample Size

In the present article, we investigate predictors of how often a scientific article is cited. Specifically, we focus on the influence of two often neglected predictors of citation rate: effect size and sample size, using samples from two psychological topical areas. Both can be considered as indicators of the importance of an article and post hoc (or observed) statistical power, and should, especially in applied fields, predict citation rates. In Study 1, effect size did not have an influence on citation rates across a topical area, both with and without controlling for numerous variables that have been previously linked to citation rates. In contrast, sample size predicted citation rates, but only while controlling for other variables. In Study 2, sample and partly effect sizes predicted citation rates, indicating that the relations vary even between scientific topical areas. Statistically significant results had more citations in Study 2 but not in Study 1. The results indicate that the importance (or power) of scientific findings may not be as strongly related to citation rate as is generally assumed.

A Bayesian mathematical model of motor and cognitive outcomes in Parkinson's disease

Background

There are few established predictors of the clinical course of PD. Prognostic markers would be useful for clinical care and research.

Objective

To identify predictors of long-term motor and cognitive outcomes and rate of progression in PD.

Methods

Newly diagnosed PD participants were followed for 7 years in a prospective study, conducted at 55 centers in the United States and Canada. Analyses were conducted in 244 participants with complete demographic, clinical, genetic, and dopamine transporter imaging data. Machine learning dynamic Bayesian graphical models were used to identify and simulate predictors and outcomes. The outcomes rate of cognition changes are assessed by the Montreal Cognitive Assessment scores, and rate of motor changes are assessed by UPDRS part-III.

Results

The most robust and consistent longitudinal predictors of cognitive function included older age, baseline Unified Parkinson’s Disease Rating Scale (UPDRS) parts I and II, Schwab and England activities of daily living scale, striatal dopamine transporter binding, and SNP rs11724635 in the gene BST1. The most consistent predictor of UPDRS part III was baseline level of activities of daily living (part II). Key findings were replicated using long-term data from an independent cohort study.

Conclusions

Baseline function near the time of Parkinson’s disease diagnosis, as measured by activities of daily living, is a consistent predictor of long-term motor and cognitive outcomes. Additional predictors identified may further characterize the expected course of Parkinson’s disease and suggest mechanisms underlying disease progression. The prognostic model developed in this study can be used to simulate the effects of the prognostic variables on motor and cognitive outcomes, and can be replicated and refined with data from independent longitudinal studies.

Physicians' role in the determination of fitness to drive in patients with Parkinson's disease: systematic review of the assessment tools and a call for national guidelines

BACKGROUND

Physicians are usually at the forefront when the issue of driving ability is raised by Parkinson's disease (PD) patients or their family members, even though few have been formally trained in this area.

OBJECTIVES AND METHODS

To identify relevant literature on driving assessment tools in patients with PD by performing a systematic review on this subject in order to provide background information for physicians on what types of driving assessment are available, and to delineate the role of physicians in providing fitness to drive recommendations.

RESULTS

Of 1,490 abstracts screened, 55 articles fulfilled the selection criteria that investigated assessment of driving ability in PD patients with questionnaires, off-road testing battery, driving simulators, and driving skill tests (on-road tests and naturalistic driving test). Despite different methodology across studies, PD patients were observed to commit more driving errors than controls. Poor driving performance correlated with motor, visual, and cognitive severity. Excessive daytime somnolence was common in PD drivers and the presence of falling asleep while driving was identified to be a significant predictor of car accidents.

CONCLUSION

Although the evidence indicated more driving errors among PD drivers as identified by various assessment tools, the extent on how physicians should be involved in the evaluation process and make related recommendations remain unclear. Driving safety is an important public health issue in PD that needs better-defined specific legal and medical guidelines. National guidelines that establish risk assessment protocols involving multidisciplinary assessments are needed to assist physicians in making appropriate referrals for additional evaluations and recommendations when patients are deemed to be unsafe drivers.

Living with Parkinson's disease: A Jordanian perspective

BACKGROUND

Parkinson's disease (PD) has a major impact on mobility, as well as cognition which can consequently impair aspects of individual's lives. Many studies have examined the living experiences of individuals with PD and its impact on their daily lives. None of these studies have explored the life experiences of Jordanian individuals living with PD. Therefore, the purpose of this qualitative study was to describe the daily living experiences and impact on lives of Jordanian individuals with PD.

METHODS

A qualitative phenomenological design was used. Interviews were recorded and transcribed. Transcripts were analysed using thematic analysis.

RESULTS

Experiences of 8 Jordanian individuals with PD who participated in this study can be categorized in the following major themes: (1) challenging perspectives and (2) adaptations. Challenging perspectives included stigma, emotional drainer, and experience of decreased independence and difficulty in occupational performance. Adaptations included embracing early acceptance and intervention, spiritual experience, and family support.

CONCLUSIONS

Study provided a wealth of knowledge related to the effect of PD and its intersection with the Arabic Jordanian culture. Such knowledge should aid healthcare professionals involved with providing services to Jordanian individuals with PD to provide better holistic services.

Establishing an evidence-base framework for driving rehabilitation in Parkinson's disease: A systematic review of on-road driving studies

BACKGROUND

Individuals with Parkinson's disease (PD) experience problems with on-road driving that can be targeted in driving rehabilitation programs.

OBJECTIVE

To provide a framework for driving rehabilitation in PD by identifying the critical on-road driving impairments and their associated visual, cognitive, and motor deficits.

METHODS

We conducted a systematic review of the literature on on-road driving and naturalistic driving practices in PD. Relevant databases including Pubmed, Medline, PsychINFO, ISI Web of Science, Cochrane library, and ClinicalTrials.gov, were reviewed using the key words Parkinson's disease, on-road driving, naturalistic driving, and their related entry words. On-road driving skills were mapped onto an existing theoretic model of operational, tactical, and strategic levels. The on-road and off-road cognitive, motor, and visual predictors of global on-road driving were summarized.

RESULTS

Twenty-seven studies were included. All but one study were prospective and Class II studies according to the American Academy of Neurology Classification Criteria. Participants were on average 68 years old and in the mild to moderate stages of PD. Drivers with PD were more likely to fail a driving assessment compared to age- and gender-matched controls. Compared with controls, drivers with PD experienced difficulties on all levels of driving skill. However, the compensation strategies on the strategic level showed that drivers with PD were aware of their diminished driving skills on the operational and strategic levels. Operational and tactical on-road driving skills best predicted global on-road driving. A combination of visual, cognitive, and motor deficits underlie impaired on-road driving performance in PD.

CONCLUSION

Driving rehabilitation strategies for individuals with PD should include training of operational and tactical driving skills or indirect comprehensive training program of visual, cognitive, and motor skills.

Impact of Deep Brain Stimulation on Daily Routine Driving Practice in Patients with Parkinson's Disease

Objective. To determine the influence of deep brain stimulation (DBS) on daily routine driving behavior in Parkinson's disease (PD) patients. Methods. A cross-sectional questionnaire survey was done in 121 DBS-PD patients. The influences of patient characteristics and DBS on current driving and driving at time of surgery and the predictive value of the preoperative levodopa-test on postoperative driving were evaluated. Results. 50% of 110 driving-license holders currently drove. 63.0% rated themselves as safe drivers, 39.4% reported improvement, and 10.9% noted deterioration in driving after DBS surgery. Inactive drivers had quit driving mainly due to disease burden (90.9%). Active drivers were younger, more often males, and less impaired according to H&Y and MMSE, had surgery more recently, and reported more often overall benefit from DBS. H&Y “on” and UPDRS III “off” scores at time of surgery were lower in pre- and postoperative active than in inactive drivers. Tremor and akinesia were less frequent reasons to quit driving after than before DBS surgery. Postoperatively, 22.7% (10/44) of patients restarted and 10.6% (7/66) of patients discontinued driving, independently of H&Y stage. The preoperative levodopa-test was not predictive for the postoperative driving outcome. Conclusion. 50% of PD patients with DBS drive. DBS surgery changes daily routine driving behavior.

Cognitive functioning differentially predicts different dimensions of older drivers' on-road safety

The extent to which deficits in specific cognitive domains contribute to older drivers' safety risk in complex real-world driving tasks is not well understood. We selected 148 drivers older than 70 years of age both with and without neurodegenerative diseases (Alzheimer disease-AD and Parkinson disease-PD) from an existing driving database of older adults. Participant assessments included on-road driving safety and cognitive functioning in visuospatial construction, speed of processing, memory, and executive functioning. The standardized on-road drive test was designed to examine multiple facets of older driver safety including navigation performance (e.g., following a route, identifying landmarks), safety errors while concurrently performing secondary navigation tasks ("on-task" safety errors), and safety errors in the absence of any secondary navigation tasks ("baseline" safety errors). The inter-correlations of these outcome measures were fair to moderate supporting their distinctiveness. Participants with diseases performed worse than the healthy aging group on all driving measures and differences between those with AD and PD were minimal. In multivariate analyses, different domains of cognitive functioning predicted distinct facets of driver safety on road. Memory and set-shifting predicted performance in navigation-related secondary tasks, speed of processing predicted on-task safety errors, and visuospatial construction predicted baseline safety errors. These findings support broad assessments of cognitive functioning to inform decisions regarding older driver safety on the road and suggest navigation performance may be useful in evaluating older driver fitness and restrictions in licensing.

Cognitive impairment and dementia in Parkinson's disease: practical issues and management

Cognitive impairment and dementia pose particular challenges in the management of patients with Parkinson's disease (PD). Decision-making capacity can render patients vulnerable in a way that requires careful ethical considerations by clinicians with respect to medical decision making, research participation, and public safety. Clinicians should discuss how future decisions will be made as early in the disease course as possible. Because of cognitive, visual, and motor impairments, PD may be associated with unsafe driving, leading to early driving cessation in many. DBS of the STN and, to a lesser degree, globus pallidus interna (GPi) has consistently been associated with decreased verbal fluency, but significant global cognitive decline is usually not observed in patients who undergo rigorous selection. There are some observations suggesting lesser cognitive decline in GPi DBS than STN DBS, but further research is required. Management of PD dementia (PDD) patients involves both pharmacological and nonpharmacological measures. Patients with PDD should be offered treatment with a cholinesterase inhibitor taking into account expected benefits and potential risks. Treatment with neuroleptics may be necessary to treat psychosis; classical neuroleptics, as well as risperidone and olanzapine, should be avoided. Quetiapine might be considered first-line treatment because it does not need special monitoring, although the strongest evidence for efficacy exists for clozapine. Evidence from randomized, controlled studies in the PDD population is lacking; selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors may be used to treat depressive features. Clonazepam or melatonin may be useful in the treatment of rapid eye movement behavior disorder.

Automobile driving in older adults: factors affecting driving restriction in men and women

OBJECTIVES

To identify factors associated with driving restriction in elderly men and women.

DESIGN

Prospective cohort study of French drivers from 2003 to 2009.

SETTING

The Three-City Cohort of Bordeaux, a prospective study of 2,104 people aged 65 and older.

PARTICIPANTS

Five hundred twenty-three drivers with a mean age of 76 (273 male, 250 female).

MEASUREMENTS

Sociodemographic characteristics, driving habits, health variables, cognitive evaluation and dementia diagnosis. Predementia was defined as no dementia at one follow-up and dementia at the next follow-up.

RESULTS

Over the 6-year period, 54% of men and 63% of women stopped driving or reduced the distance they drove. Predementia, Parkinson's disease, older age, and a high number of kilometers previously driven were common restriction factors in both sexes. Prevalent dementia, depressive symptomatology, a decline in one or more instrumental activities of daily living, and poor visual working memory were specific factors in men. In women, low income, fear of falling, slow processing speed, and severe decline in global cognitive performance all affected driving restriction.

CONCLUSION

Older women restricted their driving activity more than older men, regardless of the number of kilometers previously driven, physical health, and cognitive status. Factors affecting driving restriction differed according to sex, and women were more likely to stop driving than men in the period preceding a dementia diagnosis.

Driving errors in Parkinson's disease: moving closer to predicting on-road outcomes

Age-related medical conditions such as Parkinson's disease (PD) compromise driver fitness. Results from studies are unclear on the specific driving errors that underlie passing or failing an on-road assessment. In this study, we determined the between-group differences and quantified the on-road driving errors that predicted pass or fail on-road outcomes in 101 drivers with PD (mean age = 69.38 ± 7.43) and 138 healthy control (HC) drivers (mean age = 71.76 ± 5.08). Participants with PD had minor differences in demographics and driving habits and history but made more and different driving errors than HC participants. Drivers with PD failed the on-road test to a greater extent than HC drivers (41% vs. 9%), χ²(1) = 35.54, HC N = 138, PD N = 99, p < .001. The driving errors predicting on-road pass or fail outcomes (95% confidence interval, Nagelkerke R² =.771) were made in visual scanning, signaling, vehicle positioning, speeding (mainly underspeeding, t(61) = 7.004, p < .001, and total errors. Although it is difficult to predict on-road outcomes, this study provides a foundation for doing so.

Could deep brain stimulation help with driving for patients with Parkinson's?

For mobility impaired people with Parkinson's disease (PD), driving a car is important to maintain independency. But driving ability is getting worse with disease progression. Meanwhile surgical treatment with deep brain stimulation (DBS) of the subthalamic nucleus is done routinely in advanced PD, but it is unknown how DBS might affect driving. In a driving simulator setting, we found PD patients undergone DBS surgery to drive safer than even less clinically affected PD patients treated with medication alone. Furthermore, patients with DBS surgery drove better under stimulation than under medication. In conclusion, DBS of the subthalamic nucleus appears to be beneficial for driving in PD patients, potentially due to non-motor effects on controlling the vehicle in the simulator setting. Nevertheless, results of this first pilot study on driving in PD patients with DBS should not encourage patients or physicians to consider DBS only to improve or regain driving competence.

Randomized trial of cognitive speed of processing training in Parkinson disease

OBJECTIVE

To examine the efficacy of cognitive speed of processing training (SOPT) among individuals with Parkinson disease (PD). Moderators of SOPT were also examined.

METHODS

Eighty-seven adults, 40 years of age or older, with a diagnosis of idiopathic PD in Hoehn & Yahr stages 1-3 and on a stable medication regimen were randomized to either 20 hours of self-administered SOPT (using InSight software) or a no-contact control condition. Participants were assessed at baseline and after 3 months of training (or an equivalent delay). The primary outcome measure was useful field of view test (UFOV) performance, and secondary outcomes included cognitive self-perceptions and depressive symptoms.

RESULTS

Results indicated that participants randomized to SOPT experienced significantly greater improvements on UFOV performance relative to controls, Wilks λ = 0.938, F 1,72 = 4.79, p = 0.032, partial η(2) = 0.062. Findings indicated no significant effect of training on secondary outcomes, Wilks λ = 0.987, F2,70 < 1, p = 0.637, partial η(2) = 0.013.

CONCLUSIONS

Patients with mild to moderate stage PD can self-administer SOPT and improve their cognitive speed of processing, as indexed by UFOV (a robust predictor of driving performance in aging and PD). Further research should establish if persons with PD experience longitudinal benefits of such training and if improvements translate to benefits in functional activities such as driving.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that SOPT improves UFOV performance among persons in the mild to moderate stages of PD.

Parkinson disease and driving: an evidence-based review

The growing literature on driving in Parkinson disease (PD) has shown that driving is impaired in PD compared to healthy comparison drivers. PD is a complex neurodegenerative disorder leading to motor, cognitive, and visual impairments, all of which can affect fitness to drive. In this review, we examined studies of driving performance (on-road tests and simulators) in PD for outcome measures and their predictors. We searched through various databases and found 25 (of 99) primary studies, all published in English. Using the American Academy of Neurology criteria, a study class of evidence was assigned (I-IV, I indicating the highest level of evidence) and recommendations were made (Level A: predictive or not; B: probably predictive or not; C: possibly predictive or not; U: no recommendations). From available Class II and III studies, we identified various cognitive, visual, and motor measures that met different levels of evidence (usually Level B or C) with respect to predicting on-road and simulated driving performance. Class I studies reporting Level A recommendations for definitive predictors of driving performance in drivers with PD are needed by policy makers and clinicians to develop evidence-based guidelines.

Evaluating the driving ability in patients with Parkinson's disease using a driving simulator

OBJECTIVE

For patients with Parkinson's disease (PD), driving is challenging due to an impaired motor function and decreased attention capabilities. This study assessed the driving capacity in PD patients by comparing neurological signs.

METHODS

The driving ability of PD patients was evaluated using a driving simulator (Safety Master NT-932) that tested the reaction time in response to traffic signals and steering wheel errors. We studied the correlations between the total Unified Parkinson's Disease Rating Scale (UPDRS) score, the UPDRS part III score, the subscores of the UPDRS part III score, age, PD disease duration, braking reaction time, steering wheel errors and total scores for driving safety test results. 'On' state regular PD licensed drivers (n=42; mean age: 63 years) in Hoehn and Yahr stages II-III participated after their cognitive status was confirmed using mini-mental state examinations.

RESULTS

The UPDRS scores, the UPDRS part III scores and the postural instability subscores exhibited significant (p<0.05) correlations with the number of steering wheel errors but not with the braking reaction time or the total safety scores of the test results.

CONCLUSION

The UPDRS is an established evaluation method used to estimate PD signs, although it is not sufficient alone for deciding whether PD patients should be allowed to drive. Our findings suggest that determining the driving ability using a driving simulator might be a useful adjunct to UPDRS scores in the assessment of PD patients who are active drivers. Estimating the driving ability requires complex measurements, including motor performance with perception of stimuli and attention.

Prefrontal dopamine signaling and cognitive symptoms of Parkinson's disease

Cognitive dysfunction is a common symptom of Parkinson's disease (PD) that causes significant morbidity and mortality. The severity of these symptoms ranges from minor executive symptoms to frank dementia involving multiple domains. In the present review, we will concentrate on the aspects of cognitive impairment associated with prefrontal dopaminergic dysfunction, seen in non-demented patients with PD. These symptoms include executive dysfunction and disorders of thought, such as hallucinations and psychosis. Such symptoms may go on to predict dementia related to PD, which involves amnestic dysfunction and is typically seen later in the disease. Cognitive symptoms are associated with dysfunction in cholinergic circuits, in addition to the abnormalities in the prefrontal dopaminergic system. These circuits can be carefully studied and evaluated in PD, and could be leveraged to treat difficult clinical problems related to cognitive symptoms of PD.

Relationships between cognitive functions and driving behavior in Parkinson's disease

Alterations in cognitive functions in Parkinson's disease (PD) have been reported even in mild stages of the disease. These functions may play a role in complex daily activities, such as driving. This article provides an overview on the relationships between cognitive functions and driving behavior in PD in driving simulator and on-road studies. The role of attention, executive functions, visual memory, visuospatial construction and information processing speed is discussed. In driving simulator studies, driving performances were correlated with several neuropsychological measures, especially those of Trail Making Test (TMT), Brixton and Symbol Digit Modalities Test. In on-road studies, TMT, Useful Field Of View and Block Design tests appear as good predictors of driving performances. Most of these tests are also relevant to driving in Alzheimer's disease and traumatic brain injury.

Predictors of driving outcomes in advancing age

This study aimed to develop predictive models for real-life driving outcomes in older drivers. Demographics, driving history, on-road driving errors, and performance on visual, motor, and neuropsychological test scores at baseline were assessed in 100 older drivers (ages 65-89 years [72.7]). These variables were used to predict time to driving cessation, first moving violation, or crash. Using Cox proportional hazards regression models, significant individual predictors for driving cessation were greater age and poorer scores on Near Visual Acuity, Contrast Sensitivity, Useful Field of View, Judgment of Line Orientation, Trail Making Test-Part A, Benton Visual Retention Test, Grooved Pegboard, and a composite index of overall cognitive ability. Greater weekly mileage, higher education, and "serious" on-road errors predicted moving violations. Poorer scores from Trail Making Test-Part B or Trail Making Test (B-A) and serious on-road errors predicted crashes. Multivariate models using "off-road" predictors revealed (a) age and Contrast Sensitivity as best predictors for driving cessation; (b) education, weekly mileage, and Auditory Verbal Learning Task-Recall for moving violations; and (c) education, number of crashes over the past year, Auditory Verbal Learning Task-Recall, and Trail Making Test (B-A) for crashes. Diminished visual, motor, and cognitive abilities in older drivers can be easily and noninvasively monitored with standardized off-road tests, and performances on these measures predict involvement in motor vehicle crashes and driving cessation, even in the absence of a neurological disorder.

Cognitive functioning predicts driver safety on road tests 1 and 2 years later

OBJECTIVES

To describe longitudinal changes in mean level and evaluate rank-order stability in potential predictors of driving safety (visual sensory, motor, visual attention, and cognitive functioning) and safety errors during an 18-mile on-road driving test in older adults and to evaluate the relative predictive power of earlier visual sensory, motor, visual attention, and cognitive functioning on future safety errors, controlling for earlier driving capacity.

DESIGN

Three-year longitudinal observational study.

SETTING

Large teaching hospital in the Midwest.

PARTICIPANTS

One hundred eleven neurologically normal older adults (60-89 at baseline).

MEASUREMENTS

Safety errors based on video review of a standard 18-mile on-road driving test served as the outcome measure. A comprehensive battery of tests on the predictor side included visual sensory functioning, motor functioning, cognitive functioning, and a measure of useful field of view.

RESULTS

Longitudinal changes in mean levels of safety errors and cognitive functioning were small from year to year. Relative rank-order stability between consecutive assessments was moderate in overall safety errors and moderate to strong in visual attention and cognitive functioning. Although prospective bivariate correlations between safety errors and predictors ranged from fair to moderate, only functioning in the cognitive domain predicted future driver performance 1 and 2 years later in multivariate analyses.

CONCLUSION

Normative aging-related declines in driver performance as assessed using on-road tests emerge slowly. Even in the presence of conservative controls, such as previous driving ability, age, and visual sensory and motor functioning, cognitive functioning predicted future on-road driving performance 1 and 2 years later.