UC Merced Proceedings of the Annual Meeting of the Cognitive Science Society Title The effects of amnesia on driving performance in elderly drivers. Permalink https://escholarship.org/uc/item/6jd0198t Journal Proceedings of the Annual Meeting of the Cognitive Science Society, 34(34) ISSN 1069-7977 Authors Kawano, Naoko Iwamoto, Kunhiro Ebe, Kazutoshi et al. Publication Date 2012 Peer reviewed eScholarship.org Powered by the California Digital Library University of California The effects of amnesia on driving performance in elderly drivers Naoko Kawano ([email protected]) Department of Psychiatry, Graduate School of Medicine, Nagoya University, Japan. Kunihiro Iwamoto ([email protected]) Department of Psychiatry, Graduate School of Medicine, Nagoya University, Japan. Kazutoshi Ebe ([email protected]) Toyota Central R&D Labs., Inc., Japan. Katsuyuki Ukai ([email protected]) Kamiiida daiichi General hospital, Japan. Yusuke Suzuki ([email protected]) Department of Geriatrics, Graduate School of Medicine, Nagoya University, Japan. Hiroyuki Umegaki ([email protected]) Department of Geriatrics, Graduate School of Medicine, Nagoya University, Japan. Tetsuya Iidaka ([email protected]) Department of Psychiatry, Graduate School of Medicine, Nagoya University, Japan. Norio Ozaki ([email protected]) Department of Psychiatry, Graduate School of Medicine, Nagoya University, Japan. Abstract aging-related memory of normal controls. This difference may be associated with flexibility of visual attention and Cognitive dysfunction caused by some neurodegenerative executive function. diseases is associated with an increased risk of traffic accidents. Previous studies have reported inconsistent results Keywords: mild cognitive impairment, driving simulator, for prodromal and early stages of dementia. Few studies have Trail Making Test, elderly driver, normal aging. directly compared the effects on driving performance of amnestic subtype of mild cognitive impairment (aMCI) with Introduction those by normal aging in elderly drivers. The present study Driving is a specialized and complex action that requires the examines the association between cognitive decline and use of extensive cognitive abilities. Age-related dysfunction driving ability in elderly drivers with aMCI. The participants of the central nervous systems in people with dementia, were 19 healthy young adults (HYA), 26 healthy elderly such as symptoms caused by Alzheimer’s disease, may adults (HEA), and 12 elderly patients with aMCI. All influence driving. Studies have found that drivers with performed a road-tracking, a car-following, and a harsh- dementia have 2.5 to 4.7 times the risk of an automobile braking task on a driving simulator (DS). Elderly participants accident compared to cognitively intact elderly drivers also completed cognitive assessment tasks including measures (Cooper, Tallman, Tuokko, & Beattie, 1993; Molnar, Patel, of memory performance. All MCI participants showed a well- defined memory decline, and demonstrated significantly Marshall, Man-Son-Hing, & Wilson, 2006). Fatal motor decreased performance on the car-following and road-tracking vehicle crash rates (per miles driven) show a U-shape curve tasks as compared with the HYA group. However, the aMCI with the highest rates among the youngest and oldest drivers group also demonstrated significantly decreased performance (Hakamies-Blomqvist, Sirén, & Davidse, 2004). on the car-following task as compared with HEA. In elderly Cognitive limitations not only from some age-related participants, the car-following performance was positive neurodegenerative diseases but also from aging-related correlated with the score on the Trail Making Test-B. This normal changes are associated with an increased risk of evidence indicates a difference for driving ability between being involved in a traffic accident. Epidemiological studies individuals with symptomatic memory impairment and the demonstrated that elderly patients with mild dementia are 1762 high-risk drivers, as a group, compared with cognitively in common situations, whereas the multi-domain group intact drivers (Man-Son-Hing Marshall, Molnar, & Wilson, showed a greater increase for driving difficulty only in 2007). However, there is little evidence showing the complex situations. The aMCI showed decline in driving difference in the actual driving behaviors of individuals in frequency but did not self-report driving difficulty. The these two groups (Iverson et al., 2010). A substantial authors discussed these findings from the viewpoint of self- number of patients with a Clinical Dementia Rating Scale regulation and risk perception in their groups’ driving (CDR: Morris, 1993) scores of 0.5-1.0, which are in the behaviors. They suggested that these findings may reflect preclinical or early stage of dementia, were still able to drive impaired risk perception related to amnesia. Objective safely in an on-road driving test (Brown et al., 2005). assessment data of driving performance is still need to Iverson et al. recommend that studies are needed to identify determine actual risk assessment. the appropriate predictive factors for risky driving in patient In the present study, we considered these remaining with prodromal and mild dementia, and then to develop a problems, and examined individuals with clinical aMCI and composite system of rating risk for drivers in the early age-matched memory-intact individuals and normal young stages of dementia. adults to evaluate driving performance using a driving “Mild cognitive impairment (MCI)” is conceptualized as simulator (DS). Although many consider road testing to be a transitional state between normal cognitive aging and the gold standard to evaluate driving competence, road tests clinical dementia, with amnestic and non-amnestic subtypes are costly and can be dangerous when the driver is of MCI have been defined (Petersen & Morris, 2005). The incompetent. The DS appears to be a safe and cost-effective amnestic subtype of MCI (aMCI) is characterized by method for the objective evaluation of driving performance. memory impairment, and is often operationalized as the In order (1) to examine how cognitive state may impair Clinical Dementia Rating Scale score of 0.5. People with driving performance in patients with a prodromal stage of aMCI progress to Alzheimer’s disease (AD) at a rate of 8- dementia, and (2) to identify cognitive variables explaining 15% per year, as compared to the normal aging with a the deterioration of driving performance in the aMCI group, dementia progression rate of 1-2% per year (Petersen et al., we designed a case-control study to compare the driving 2001). Therefore aMCI is considered a prodromal syndrome performance decline between adults with clinical aMCI and of AD, and often precedes the onset of dementia. elderly adults with an intact memory, based on the Individuals with MCI may be at risk for decline in performance of normal young adults. everyday complex functions, including driving. However, we have limited information about the crash risk and driving Method behaviors of individuals with clinical MCI (Man-Son-Hing et al., 2007). Recently, Frittelli et al. (2009) reported that Participants MCI had a limited effect on driving performance on a We recruited 19 healthy young adults (HYA: 39.3 years old, driving simulator, and that AD patients’ unsafe driving SD = 6.5), 26 healthy elderly adults (HEA: 70.0 years old, behavior was not predicted by their MMSE scores. They SD = 6.1), and 12 elderly patients with aMCI (71.8 years compared patients with mild AD and with MCI and age- old, SD = 7.6). The participants were naïve with regard to matched neurologically normal controls. However, it is not this study, and were paid for their participation. All were clear which cognitive characteristics of individuals with active drivers with more than 10 years of driving experience. MCI do endorse safer driving performance or which do not. They all had normal or corrected-to-normal vision, and no O’Connor, Edwards, Walley, and Crowe (2011) reported history of cerebral vascular events. associations between driving behaviors, assessed by a self- The Nagoya University Graduate School of Medicine and report questioners, and classification of MCI. Their sample Nagoya University Hospital ethics review committee was a subset of the mobility data (n = 2381) in the approved this study. Written informed consent was obtained Advanced Cognitive Training for Independent and Vital from all participant prior to their participation. Elderly (ACTIVE) study (N = 2802), and the subset All participants were examined by an experienced included 82 individuals with the aMCI, 140 individuals with psychologist who used the same task order. They had no the non-amnestic subtype of MCI, and 82 individuals with history of psychiatric problem as assessed by the Structured multi-domain subtype of MCI, and normal controls. They Clinical Interview for DSM-IV (SCID: First, Spitzer, investigated psychometrically well-defined MCI at baseline Gibbon, & Williams, 1997). The HYA and HEA individuals as a predictor in a five years follow-up of changes in driving were recruited in non-clinical setting, and had no behaviors. Their results suggested that MCI status predicted impairment in activities daily living (ADL) and no evidence declines in driving frequency and increases in driving of dementia on the Clinical Dementia Rating Scale (CDR = difficulty. The classification of MCI subtypes predicted