Association between Muscle Strength and Cardiovascular Disease Risk across Glycemic Status Groups: A Prospective Nationwide Cohort Study.

OBJECTIVE

We aimed to investigate the independent and combined associations of grip strength and chair-rising time with cardiovascular disease (CVD) risk among middle-aged and older adults across different glycemic status groups.

METHODS

This study included 7,258 CVD-free middle-aged and older adults from the China Health and Retirement Longitudinal Study (CHARLS). Muscle strength was assessed based on grip strength and chair-rising time. Incident CVD was defined as a physician-diagnosed heart disease and/or stroke. Cox proportional hazard models and restricted cubic spline analyses were used to quantify the association between muscle strength and CVD.

RESULTS

During a mean follow-up of 7.8 years, 1,785 participants (24.6%) developed incident CVD. Both lower normalized grip strength and longer chair-rising time were independently associated with increased CVD risk in a dose-dependent manner ( P for trend < 0.001), with adjusted hazard ratios ( HRs) of 1.37 (95% CI: 1.17-1.61) for the lowest vs. highest grip strength quartile and 1.53 (95% CI: 1.32-1.77) for the longest vs. shortest chair-rising time quartile. The combination of weakest grip and slowest chair-rising time conferred the highest risk ( HR = 2.12; 95% CI: 1.65-2.73). Lower grip strength and prolonged chair-rising time were associated with elevated CVD risk across all glycemic status groups. The association with grip strength reached statistical significance in the normal glucose regulation and prediabetes groups, with a similar point estimate observed in the diabetes group ( P for interaction = 0.622).

CONCLUSION

This study revealed a dose-dependent association between muscle strength and the incidence of CVD. The associations between lower grip strength and prolonged chair-rising time with higher CVD risk were directionally consistent across the glycemic status groups, although not all strata reached statistical significance.