Abstract T P128: Dual Task Walking Reveals Cognitive Dysfunction in Community-Dwelling Elderly Subjects: The Sefuri Brain MRI Study

Abstract

Introduction: The aim of our study was to investigate the effects of subclinical brain lesions and cognitive function on gait performance with or without concurrent cognitive task (i.e., dual task) in community-dwelling elderly subjects. Subjects and Methods: Between 2010 and 2012, magnetic resonance imaging (MRI) scans were performed for 170 non-demented volunteers (82 men and 88 women with a mean age of 67.5 years). The National Hospital Organization Hizen Psychiatric Center Institutional Review Board approved the study. All participants underwent neuropsychological tests (the Mini Mental State Examination [MMSE], Trail Making Test [TMT] and Rivermead Behavioral Memory Test [RBMT]). Time to complete the Timed Up and Go test was measured under two conditions: 1) Timed Up and Go test, and 2) dual task, walking while adding 3 to a predefined number “1”. Impaired gait velocity was defined as the most prolonged quintile in the time of single (>9.0 sec) and dual (>11.0 sec) tasks. We determined indices for atrophy using Voxcel-based Specific Regional Analysis for Alzheimer’s disease (VSRAD). Multivariate analysis was done using the logistic regression analysis with IBM SPSS Statistics 18 software for Windows. Results: Mean education years was 11.3±2.1 (S.D.) years, and mean MMSE score was 27.8±2.1. Silent brain infarction, deep white matter lesions (DWMLs), periventricular hyperintensities and cerebral microbleeds were detected in 19 (11.2%), 50 (29.4%), 24 (14.1%) and 8 (4.7%), respectively. Impaired gait velocity of single task (Timed Up and Go test) was associated with DWMLs (OR 2.57, 95% CI 1.16-5.69) after adjusted for age, sex, education, MMSE, TMT, RBMT, and MRI findings. Impaired gait velocity of the dual task walking was associated with age (OR 3.59/10 years, 95% CI 1.91-6.73) and score of the RBMT (OR 0.88, 95% CI 0.79-0.99), whereas MRI findings including brain atrophy (VSRAD) were not associated with reduced speed of dual task walking. Conclusions: Gait disturbance detected by single task was related to DWMLs, while dual task walking revealed an association between reduced gait speed and cognitive dysfunction. The present study showed that gait represents not only physical functioning but also cognitive dysfunction in healthy elderly individuals.