Physiological and cognitive determinants of gait in middle-aged, older-aged and oldest-aged Asian adults - The Yishun study

Background: This cross-sectional study aimed to identify and compare the contributions of physiological and cognitive performance to variations in gait characteristics in middle-aged (41-60 years), older-aged (61-70 years) and oldest-aged adults ( > 70 years). Methods: A total of 385 community-dwelling, well-functioning adults, aged 41-90 years, were randomly recruited into the study. The participants were divided into three age groups: middle-aged, older-aged and oldest-aged adults. Demographic data, height, weight, education level and information on comorbidities were recorded. Cognition was measured using the Repeatable Battery for the Assessment of Neuropsychological Status. Physiological performance included visual contrast sensitivity (VCS), postural sway, gait analysis, hand reaction time, handgrip strength (HGS) and knee extensor strength (KES). Multivariable regression tests were used to examine the association between physiological and cognitive performance with gait characteristics in age-stratified analyses. Results: HGS contributed significantly to gait variances in the middle-aged adults. KES and attention were the main determinants of gait speed and phase domain of gait for the older-aged adults. In the oldest-aged adults, HGS ( 5= -0.32 , p < 0.01), VCS ( 5= -0.22 , p < 0.01) and immediate memory ( 5= -0.24 , p = 0.04) were significant determinants of double support time (%). Conclusion: The difference in cognitive determinant of gait variances between the older-aged and oldest-aged adults could possibly due to greater reliance on immediate memory to process multisensory input, compensating for degeneration of sensorimotor system. Our findings affirmed a) the relevance of targeted physiological and cognitive assessments to better understand gait characteristics in different adult age groups; and b) the importance of HGS and KES in geriatric assessment.