Abstract
This study explores the relationship between hand grip strength (HGS) and cognitive function in China's middle-aged and elderly population. We employed a cross-sectional design using data from 4535 participants aged ≥ 45 years from the 2015 China Health and Retirement Longitudinal Study national dataset. The relationships between HGS and various dimensions of cognitive function, as well as the association between HGS and cognitive impairment, were investigated using ordinary least squares regression models and logistic regression models. Dose-response relationships between HGS and cognitive impairment were modeled using restricted cubic spline curves. Subgroup and sensitivity analyses were performed to assess the robustness of the results. The results indicated a progressive increase in the total cognitive score as well as the 4 dimensions of the score: orientation, memory, calculation, and drawing, as HGS increased (P < .001). Adjusted logistic regression models showed that the proportion of individuals with cognitive impairment was lower in the medium HGS group (OR = 0.52, 95% CI: 0.35-0.76) and even lower in the high HGS group (OR = 0.31, 95% CI: 0.18-0.54) compared to the low HGS group. A linear dose-response relationship was observed between HGS and the prevalence of cognitive impairment, after adjusting for confounders in Model 4 (nonlinear P = .155). The sensitivity analysis results aligned with those from the primary ordinary least squares and logistic regression models. Subgroup analysis revealed that men with higher HGS had a higher risk of cognitive impairment compared to women with higher HGS. The present study demonstrated a correlation between HGS and cognitive function in a Chinese middle-aged and older population and suggests that HGS may be an important risk factor for cognitive impairment.