Gait speed, life-space mobility and mild cognitive impairment in patients with coronary artery disease.

Slow gait speed and restricted life-space mobility predict cognitive decline and dementia in healthy older adults, yet the relation between gait speed or life-space mobility and cognitive function remains poorly understood in patients with coronary artery disease (CAD). We, therefore, examined the following relations: that between gait speed and cognitive function, and mild cognitive impairment (MCI) and that between life-space mobility and cognitive function, and MCI. We conducted a cross-sectional study of 240 non-dementia patients who met the study criteria from 2132 consecutive CAD patients. MCI was estimated with the Japanese version of the Montreal Cognitive Assessment (MoCA-J). Gait speed was measured to perform gait trials at the patients' usual walking pace, and life-space mobility was evaluated using the Life-Space Assessment (LSA). We investigated the relation between gait speed or life-space mobility and cognitive function by Pearson correlation analysis, whereas multivariable logistic regression analysis was conducted for detecting MCI. Gait speed and LSA scores were positively associated with the MoCA-J score (r = 0.54, p < 0.001 and r = 0.44, p < 0.001, respectively), and both were independently associated with MCI in the multivariable logistic regression analysis (odds ratio 0.007, p < 0.001, and odds ratio 0.98, p = 0.038, respectively). Cognitive impairment can be easily detected by assessment of gait speed and life-space mobility. Interventions to improve gait speed and life-space mobility may lead to the improvement of cognitive function and MCI in patients with CAD.