The relationships of grip strength and gait speed with cognitive function in a diverse cohort: Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) Study

Abstract

AbstractBackgroundGrip strength and gait speed, indicators of frailty, have been associated with poor cognitive outcomes. Whether there are differences in these associations by race/ethnicity is unknown. In the Kaiser Healthy Aging and Diverse Life Experiences (KHANDLE) Study, we examined the cross‐sectional associations of grip strength and gait speed with cognition.MethodKHANDLE aimed to evaluate how race/ethnicity and life‐course health influence late‐life brain health among community‐dwelling adults ages 65+ living in Northern California. Analysis included 1,353 Asian (24%), Black (26%), Latino (18%), and White (32%) participants. Grip strength (kg) was measured using a hand‐held dynamometer and gait speed measured a timed 4‐meter walk (m/s). Cognitive domains of verbal episodic memory, semantic memory, and executive function were measured using the Spanish and English Neuropsychological Assessment Scales (SENAS). Z‐standardized test scores were averaged for a global z‐score. Linear regression was used to assess the associations of grip strength and gait speed with cognition. Models were adjusted for demographic (age, education, income), physical (waist circumference), and behavioral risk factors (physical activity, smoking status, alcohol consumption). Gender and race/ethnicity interactions were tested separately.ResultParticipants had a mean age of 76 (SD=7) years and 58% were women. The associations of grip strength and gait speed with cognition did not differ by gender. A standard deviation (SD) increase in grip strength was associated with better global cognition [β=0.11(0.06, 0.15)]. This association did not differ by race/ethnicity and was similar across cognitive domains [executive β=0.07(0.03, 0.12); semantic β=0.12(0.07, 0.17); verbal β=0.06(0.01, 0.11)]. A SD decrease in gait speed was associated with worse global cognition [β=‐0.09(‐0.12, ‐0.06)] and associations were consistent across domains [executive β=‐0.08(‐0.11, ‐0.05); semantic β=‐0.08(‐0.11, ‐0.05); verbal β=‐0.06(‐0.09, ‐0.02)]. There were significant race/ethnicity interactions on the associations of gait speed with global cognition (p=0.001), executive function (p=0.02), and semantic memory (p=0.0004). Decreased gait speed was associated with worse cognition in these domains for Asians, Latinos, and Whites, but not associated in Blacks.ConclusionGrip strength and gait speed were cross‐sectionally associated with cognition. There were race/ethnicity differences in the association of gait speed with executive function, semantic memory, as well as global cognition.