Background: Emerging evidences indicate that mid-arm muscle circumference (MAMC) is one of the anthropometric indicators that reflect health and nutritional status, but its correlative effectiveness in all-cause mortality prediction of United States individuals remains uncertain.
Methods and findings design: We investigated the joint association between MAMC and all-cause mortality in the US general population. A population-based longitudinal study of 6,769 participants aged 40 to 90 years in the third National Health and Nutrition Examination Survey (NHANES III) conducted by the National Center for Health Statistics of the Centers for Disease Control and Prevention. All participants were divided into two groups based on the gender: male and female group; each group was then divided into three subgroups depending on their MAMC level. The tertiles were as follows: T1 (18<27.3), T2 (27.3<29.6), T3 (29.6≤40.0) cm in the male group and T1 (15<22.3), T2 (22.3<24.6), T3 (24.6≤44.0) cm in the female group. Multivariable Cox regression analyses and Kaplan-Meier survival probabilities were utilized to jointly relate all-cause mortality risk to different MAMC level. For all-cause mortality in male participants, multivariable adjusted hazard ratios (HRs) were 0.83 (95% confidence interval (CI): 0.69-0.98; p = 0.033) for MAMC of 27.3-29.6 cm compared with 18-27.3 cm, and 0.76 (95% CI: 0.61-0.95; p = 0.018) for MAMC of 29.6-40 cm compared with 18-27.3 cm. For all-cause mortality in female participants, multivariable adjusted hazard ratios (HRs) were 0.84 (95% confidence interval (CI): 0.69-1.02; p = 0.075) for MAMC of 22.3-24.6 cm compared with 15-22.3 cm, and 0.94 (95% CI: 0.75-1.17; p = 0.583) for MAMC of 24.6-44 cm compared with 15-22.3 cm.
Conclusion: Results support a lower MAMC is associated with a higher mortality risk in male individuals.