Abstract
BACKGROUND: The role of multi-site muscle strength in the incidence of chronic kidney disease (CKD) remains largely unknown. This study aims to investigate the association of combined left and right handgrip strength (CHS) with new-onset CKD in middle-aged and older adults. METHODS: This observational multicenter study included 4618 community-dwelling adults without CKD at baseline in 2011. CHS (kg) was assessed at baseline and participants were followed in 2013, 2015, and 2018 to track CKD incidents. Sex-specific thresholds for low CHS were determined using receiver operating characteristic (ROC) analysis. Restricted cubic spline analysis, survival analysis and multivariable-adjusted Cox regression models were used to analyze the association between CHS and new-onset CKD. RESULTS: The study included 2526 women and 2092 men (median age = 58.87 years). During the seven-year follow-up, 503 (10.89%) new CKD cases occurred. CHS was associated with new-onset CKD in both men (P = 0.021) and women (P = 0.009) in a linear-like manner (both P nonlinearity > 0.05). The optimal thresholds for CHS to predict CKD incidents were 96.15 kg for men and 57.90 kg for women. Kaplan-Meier curves demonstrated that prolonged CHS were positively associated with new-onset CKD in both men (P < 0.001) and women (P = 0.001). Low CHS, defined using the optimal thresholds, was independently associated with an increased risk of CKD (HR = 1.824, 95% CI = 1.379 to 2.413). This relationship was strengthened in participants with a BMI classification of normal (HR = 2.878, 95% CI = 1.732 to 4.782, P interaction = 0.032) at baseline, as well as those without diabetes (HR = 2.048, 95% CI = 1.514 to 2.771, P interaction = 0.019). CONCLUSIONS: This study demonstrated a longitudinal association between CHS and new-onset CKD in middle-aged and older Chinese adults. These findings highlight the potential of early-life multi-site muscle strength interventions for the prevention of CKD.