Independent and combined associations of handgrip strength and walking speed with cognitive function in older adults: evidence from a national cross-sectional study.

Objectives: Although there have been studies on the association of handgrip strength or walking speed alone with cognitive abilities, few studies have determined the combined associations of handgrip strength and walking speed with cognitive function. Therefore we aimed to explore the independent and combined associations of handgrip strength and walking speed with cognitive function in Chinese older adults using a nationally representative sample.

Method: This cross-sectional study included 4,577 adults aged 60 and older. Handgrip strength was measured using a dynamometer and walking speed was assessed using a 2.5-meter walking test. Both handgrip strength and walking speed were organized into low, normal, and high tertiles according to the sample distribution. Cognitive function was measured using the Telephone Interview for Cognitive Status.

Results: Handgrip strength and walking speed were significantly associated with cognitive function. Participants with low handgrip strength or low walking speed separately had a higher rate of lower cognitive function (adjusted odds ratio (OR): 1.22 (95% CI: 1.04 - 1.44) for low handgrip strength; 1.54 (95% CI: 1.31 - 1.81) for low walking speed). Those with both low handgrip strength and low walking speed had an additively higher rate of lower cognitive function (adjusted OR: 1.72 (95% CI: 1.32 - 2.24)).

Conclusion: Having low handgrip strength or low walking speed is associated with a greater likelihood of lower cognitive function and vice versa. The concurrence of having low handgrip strength and low walking speed has an additive effect on cognitive function in older adults.