IL15 and sarcopenia: These studies showed that interleukin-6 (IL-6) and tumor necrosis factor–alpha (TNF-α) were related to the risk of sarcopenia (23, 24), whereas other studies showed the risk factor of circulating cytokines was TNF-α, IL-6, IL-8, IL-15, and monocyte chemotactic protein-1 (MCP-1) was demonstrated as a risk factor for sarcopenia (25–27).