[Relationship between fibroblast growth factor-21, muscle mass, and function outcomes in overweight and obese older adults living in the community. An exploratory study]. / Relación del factor de crecimiento de fibroblastos 21 con indicadores de masa y función muscular en personas mayores con sobrepeso u obesidad. Estudio exploratorio.

BACKGROUND: Age-related decreases in muscle mass and function are associated with the development of metabolic impairments, particularly in the context of obesity. Fibroblast growth factor21 (FGF-21) has been suggested as a common mediator of both processes. No known studies have examined the association between FGF-21 and muscle mass and function in overweight or obese older adults. With this in mind, this study aimed to investigate the association between plasma levels of FGF-21 and muscle mass and function outcomes in overweight or obese older adults. MATERIALS AND METHODS: Exploratory study, which included 39 adults of 60-70years old with body mass indexes >25kg/m2. As study outcomes, measurements were made of appendicular muscle mass (AMM), grip strength, 5 times sit-to-stand test (5xSTT), as well as plasma levels of FGF-21, fasting glucose, and insulin. The homeostatic model assessment index (HOMA-IR) was also calculated to determine the presence of insulin resistance. RESULTS: Significant relationships were found between plasma levels of FGF-21 vs 5xSTT (rho=0.49; P<.05). Moreover, FGF-21 levels were significantly higher in those with insulin resistance (P<.05), as well as with having lower levels of AMM (P<.05). CONCLUSION: There is a relationship between the plasma levels of FGF-21 and muscle function outcomes in overweight or obese older adults. Future studies should investigate the potential causalities between these relationships.