Higher uric acid serum levels are associated with better muscle function in the oldest old: Results from the Mugello Study

Background: Sarcopenia is the progressive loss of muscle mass and strength that occurs with advancing age and plays a pivotal role in the causal pathway leading to frailty, disability and, eventually, to death among older persons. As oxidative damage of muscle proteins has been shown to be a relevant contributory factor, in this study we hypothesized that uric acid (UA), a powerful endogenous antioxidant, might exert a protective effect on muscle function in the oldest old and we tested our hypothesis in a group of nonagenarians who participated in the Mugello Study. Methods: 239 subjects, 73 men and 166 women, mean age 92.8 years +/- SD 3.1, underwent the assessment of UA serum level and isometric handgrip strength, a widely used clinical measure of sarcopenia. Results: Mean UA serumlevel was 5.69 mg/dL +/- SD 1.70 and mean handgrip strength was 15.0 kg +/- SD 6.9. After adjusting for relevant confounders, higher UA serum levels remained independent positive predictors of isometric handgrip strength (beta 1.24 +/- SE(beta) 0.43, p = 0.005). Conclusion: Our results show that higher UA serum levels are associated with better muscle function in the oldest old and, accordingly, might slow down the progression of sarcopenia. (C) 2017 European Federation of Internal Medicine. Published by Elsevier B. V. All rights reserved.