Cumulative Muscle Strength and Risk of Cardiovascular Disease and All-cause mortality: A Prospective Cohort Study.

BACKGROUND: The existing literature regarding the association between muscle strength and cardiovascular disease (CVD) and all-cause mortality relies mostly on a single measurement of muscle strength but has seldomly focused on the accumulated exposure.

OBJECTIVE: This study explored the association between cumulative muscle strength and risks of CVD and all-cause mortality in middle-aged and older adults.

METHODS: A total of 6,972 patients from the China Health and Retirement Longitudinal Study, who underwent 3 repeated measurements of muscle strength over 4 years and were followed-up for another 3 years for CVD and all-cause mortality outcomes participated in this study. Muscle strength was evaluated by grip strength and chair-rising time. Cumulative muscle strength was calculated as the area under the curve. Odds ratio (OR) and 95% confidence intervals (CIs) were analyzed.

RESULTS: The odds of CVD and all-cause mortality decreased as cumulative grip strength increased or cumulative chair-rising time decreased. For each 1 standard deviation (SD) increment in cumulative grip strength, the multivariable-adjusted OR for CVD and all-cause mortality were 0.81 (95% CI 0.73-0.91) and 0.85 (95% CI 0.73-0.99), respectively. For each 1 SD decrease in cumulative chair-rising time, the corresponding OR were 0.81 (95% CI 0.75-0.88) and 0.87 (95% CI 0.77-0.98), respectively. However, neither the change-slope of grip strength nor that of chair-rising time was related to decreased OR of CVD or of all-cause mortality.

CONCLUSIONS: Cumulative muscle strength was associated with a reduced risk of CVD and all-cause mortality in middle-aged and older Chinese adults.