Inverse association between circulating adiponectin levels and skeletal muscle strength in Japanese men and women

Background and aims: Increased levels of circulating adiponectin in the elderly cause a negative impact on physical function and health status, which suggests that circulating adiponectin may be related to skeletal muscle function. However, data on the relationship between circulating adiponectin levels and skeletal muscle function is limited. Our objective was to investigate the association between serum adiponectin levels and muscle strength in adults. Methods and results: This cross-sectional study is a part of the Oroshisho Study of adult employees in Japan from 2008 to 2011. In our study, we used data gathered in 2008-2010 that had included serum adiponectin measurements (n=1378; age, 19-83 years). From this population, 1259 subjects were evaluated for grip strength (949 men, 310 women), and 965 subjects were evaluated for leg extension power (716 men, 249 women). Multivariate linear regression analyses showed that adiponectin was associated significantly and negatively with both grip strength (β and standard error [SE]: men, -0.09 [0.01], p=0.010; women, -0.20 [0.03], kg, p=0.002) and leg extension power (men, -0.09 [0.02], p=0.014; women, -0.14 [0.07], W, p=0.032) after adjusting for age, physical activity, nutrient intake, depressive symptoms, metabolic syndrome, C-reactive protein, body mass index, and other lifestyle-related potential confounders. Conclusion: This population-based cross-sectional study indicates an inverse association between serum adiponectin levels and muscle strength in adults. Further studies are necessary to confirm this association and to clarify causality.