Association between change in handgrip strength and cognitive function in Korean adults: a longitudinal panel study

Background: Muscular function, such as handgrip strength, has been suggested as an associated factor for cognitive impairment. This study investigated the association between temporal change in handgrip strength and cognitive function using longitudinal, nationwide data from Korean older adults. Methods: Our study used data from the Korean Longitudinal Study of Aging (KLoSA). The analysis covered 6696 participants who had taken the handgrip strength test and Mini-Mental State Examination (MMSE) from 2006 to 2018. We adopted general estimating equations to assess the temporal effect of handgrip strength change on cognitive function. Results: After adjusting for covariates, we observed an association between handgrip strength and low MMSE scores (β = − 0.3142 in men, β = − 0.2685 in women). Handgrip strength as a continuous variable was positively correlated with MMSE scores after adjustment (β = 0.0293 in men, β = 0.0347 in women). The group with decreased handgrip strength over time also showed greater odds for mild cognitive impairment (OR = 1.23, 95%CI = 1.05–1.27 in men, OR = 1.15, 95%CI = 1.05–1.27 in women) and dementia (OR = 1.393, 95%CI = 1.18–1.65 in men, OR = 1.19, 95%CI = 1.08–1.32 in women). Conclusions: This study identified the relationship between handgrip strength change and cognitive function among South Korean adults. According to our large, longitudinal sample, decreasing handgrip strength was associated with decline in cognitive function.