Linear association between grip strength and all-cause mortality among the elderly: results from the SHARE study.

BACKGROUND: Grip strength had become a potential tool for clinical assessments, while the predictive value of the grip strength of community-based populations had some limitations. AIMS: To identify the shapes of the association between grip strength and all-cause mortality in the Survey of Health, Ageing and Retirement in Europe (SHARE) cohort. METHODS: Based on the SHARE cohort, 13,231 subjects aged 65 years and older were included in this study. Cox models with penalized splines (P-splines) were employed to characterize the shapes of the association between grip strength and all-cause mortality with the adjustment of covariates including sociodemographic characteristics, health characteristics, behavioral habits, and illness status. Then grip strength was analyzed as a categorical variable in quintile to examine the impact of low grip strength on all-cause mortality. RESULTS: Inversely linear associations were found between grip strength and mortality both in males and females after adjustment for covariates. The hazard ratios (HRs) and their 95% confidence intervals (CIs) for each 5 kg decrease in grip strength to all-cause mortality were 1.11 (1.06-1.18) in males and 1.17 (1.08-1.28) in females. In comparison with subjects in the fifth quintile, the adjusted HRs and 95% CIs of all-cause mortality in the first quintile was 2.39 (1.79-3.19) in males and 1.84 (1.34-2.51) in females. Which were statistically significant in the second quintile compared with the fifth quintile [Males: 2.06 (1.56, 2.74), Females: 1.83 (1.35, 2.48)]. CONCLUSIONS: Grip strength is inversely linear association with all-cause mortality and the low grip strength at the first and second quintile are a robust predictor of all-cause mortality.