The impact of cognitive deficit on self-reported car crashes in ultra-octogenarian population: data of an Italian population-based study

Car Accidents Associated with Physical Frailty and Cognitive Impairment

INTRODUCTION

Age-related functional decline elevates the risk of car accidents. Whether specific cognitive impairments and physical frailty increase the risk of car accidents is still unclarified.

OBJECTIVE

This study examines the association between car accidents, frailty, and cognitive function, owing to an increase in car accidents related to older adults.

METHODS

Data were collected from 12,013 older adults (45.4% women, mean age: 71.7 years [min: 60, max: 96]) enrolled in the National Center for Geriatrics and Gerontology (NCGG) - Study of Geriatric Syndromes. A 2-year self-reported history of car accidents was assessed. The Japanese cardiovascular health study index was used as the criterion and included the following components of frailty: shrinking, weakness, exhaustion, low activity, and slowness. "Frailty" was assigned a value of 1 or more based on these components. Cognitive function was assessed using the NCGG Functional Assessment Tool, and cognitive impairment was assessed using a standardized value.

RESULTS

Of the participants, 1,117 (9.3%) had a car accident history. The proportions of the frailty components' applicability were observed in the car accidents group compared to the non-car accidents group: shrinking (p = 0.006), exhaustion (p = 0.031), low activity (p = 0.034), and slowness (p = 0.030), but not weakness (p = 0.452). The proportion of cognitive impairment in executive function was also higher in the car accidents group (p = 0.011). A logistic regression analysis showed that both frailty (OR 1.26, 95% CI 1.11-1.43; p < 0.001) and cognitive impairment (OR 1.26, 95% CI 1.11-1.43, p < 0.001) are associated with car accidents.

DISCUSSION

This study's findings contribute to enhancing the utility of risk assessments for older drivers. Further study is required to clarify the risk of car accidents.

Associations of Near-Miss Traffic Incidents with Attention and Executive Function among Older Japanese Drivers

Background: Attention and executive function may play an important role in ensuring safe driving as they involve paying attention to complex information and making an instantaneous judgment during driving. We hypothesized that poor performance in attention and executive function may increase the risk of near-miss incidents among older drivers. Objective: The aim of this study was to examine associations of current experience of near-miss traffic incidents with attention and executive function among older Japanese drivers. Methods: The study included 3,421 general older drivers (mean age: 71.7 ± 4.9 years; 56.3% men) with a valid driver’s license who were currently driving at least once per week and who had participated in a community-based cohort study between February 2015 and August 2016. The participants were asked about their experiences of near-miss traffic incidents in 10 situations that had almost happened during driving in the previous year. Results: Of the 3,421 older drivers, 1,840 (53.8%) had experienced near-miss incidents during driving in the previous year at least once. Male sex (OR 1.46, 95% CI 1.27–1.69) and high driving frequency (OR 1.11, 95% CI 1.07–1.15) were significantly associated with the current experience of near-miss traffic incidents when the overall data were analyzed. In young-old drivers aged 65–74 years, poor performance in attention as assessed by the Trail Making Test-part A (OR 1.45, 95% CI 1.05–2.00) was significantly associated with near-miss traffic incidents. Conclusion: Male sex, high driving frequency, and poor performance in attention (in young-old drivers) were associated with near-miss traffic incidents. Improvement in attention may play a role in decreasing the risk of traffic accidents among older drivers.

The trail making test as a screening instrument for driving performance in older drivers; a translational research

BACKGROUND

In many countries, primary care physicians determine whether or not older drivers are fit to drive. Little, however, is known regarding the effects of cognitive decline on driving performance and the means to detect it. This study explores to what extent the trail making test (TMT) can provide indications to clinicians about their older patients' on-road driving performance in the context of cognitive decline.

METHODS

This translational study was nested within a cohort study and an exploratory psychophysics study. The target population of interest was constituted of older drivers in the absence of important cognitive or physical disorders. We therefore recruited and tested 404 home-dwelling drivers, aged 70 years or more and in possession of valid drivers' licenses, who volunteered to participate in a driving refresher course. Forty-five drivers also agreed to undergo further testing at our lab. On-road driving performance was evaluated by instructors during a 45 minute validated open-road circuit. Drivers were classified as either being excellent, good, moderate, or poor depending on their score on a standardized evaluation of on-road driving performance.

RESULTS

The area under the receiver operator curve for detecting poorly performing drivers was 0.668 (CI95% 0.558 to 0.778) for the TMT-A, and 0.662 (CI95% 0.542 to 0.783) for the TMT-B. TMT was related to contrast sensitivity, motion direction, orientation discrimination, working memory, verbal fluency, and literacy. Older patients with a TMT-A ≥ 54 seconds or a TMT-B ≥ 150 seconds have a threefold (CI95% 1.3 to 7.0) increased risk of performing poorly during the on-road evaluation. TMT had a sensitivity of 63.6%, a specificity of 64.9%, a positive predictive value of 9.5%, and a negative predictive value of 96.9%.

CONCLUSION

In screening settings, the TMT would have clinicians uselessly consider driving cessation in nine drivers out of ten. Given the important negative impact this could have on older drivers, this study confirms the TMT not to be specific enough for clinicians to justify driving cessation without complementary investigations on driving behaviors.

Systematic review of the evidence for Trails B cut-off scores in assessing fitness-to-drive

Background

Fitness-to-drive guidelines recommend employing the Trail Making B Test (a.k.a. Trails B), but do not provide guidance regarding cut-off scores. There is ongoing debate regarding the optimal cut-off score on the Trails B test.

The objective of this study was to address this controversy by systematically reviewing the evidence for specific Trails B cut-off scores (e.g., cut-offs in both time to completion and number of errors) with respect to fitness-to-drive.

Methods

Systematic review of all prospective cohort, retrospective cohort, case-control, correlation, and cross-sectional studies reporting the ability of the Trails B to predict driving safety that were published in English-language, peer-reviewed journals.

Results

Forty-seven articles were reviewed. None of the articles justified sample sizes via formal calculations. Cut-off scores reported based on research include: 90 seconds, 133 seconds, 147 seconds, 180 seconds, and < 3 errors.

Conclusions

There is support for the previously published Trails B cut-offs of 3 minutes or 3 errors (the ‘3 or 3 rule’). Major methodological limitations of this body of research were uncovered including (1) lack of justification of sample size leaving studies open to Type II error (i.e., false negative findings), and (2) excessive focus on associations rather than clinically useful cut-off scores.