Cognitive function and gait speed under normal and dual-task walking among older adults with mild cognitive impairment.
BACKGROUND
Gait ability and cognitive function are interrelated during both normal walking (NW) and dual-task walking (DTW), and gait ability is thus adversely affected by cognitive impairment in both situations. However, this association is insufficiently understood in people with mild cognitive impairment (MCI). Here, we conducted a study with MCI participants, to examine whether the association depends on walking conditions and MCI subtypes.


METHODS
We classified 389 elderly adults into amnestic MCI (n = 191) and non-amnestic MCI (n = 198), assessed their cognitive functions, and administered gait experiments under NW and DTW conditions. Gait ability was defined as gait speed. Five aspects of cognitive function were assessed: processing speed, executive function, working memory, verbal memory, and visual memory.


RESULTS
Regression analysis adjusted for covariates showed a significant association between cognitive functions and gait speed. Processing speed and executive function correlated with gait speed during both NW and DTW (p < .05). Gait speed during DTW was also significantly associated with working memory (p < .001). Visual memory was associated during NW and DTW, particularly for amnestic MCI participants (p < .05).


CONCLUSIONS
Our findings support the idea that the association between gait speed and cognitive function depends on walking condition and MCI subtypes. Additional studies are necessary to determine the neural basis for the disruption in gait control in older adults with MCI.
Section for Health Promotion, Department for Research and Development to Support Independent Life of Elderly, Center for Gerontology and Social Science, National Center for Geriatrics and Gerontology, 35 Gengo, Morioka, Obu, Aichi 474-8511, Japan. take-d@ncgg.go.jp.
Takehiko
T
Doi
Hiroyuki
H
Shimada
Hyuma
H
Makizako
Kota
K
Tsutsumimoto
Kazuki
K
Uemura
Yuya
Y
Anan
Takao
T
Suzuki
D001288:Attention; D003071:Cognition; D060825:Cognitive Dysfunction / Q000150:complications*; D015331:Cohort Studies; D005260:Female; D005684:Gait; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D013647:Task Performance and Analysis; D016138:Walking