SELP and sarcopenia: Participants with high P-selectin (>17.28 ng/mL) exhibited increased odds of sarcopenia (multivariate OR = 4.20, 95% CI: 1.82-9.69, <i>p</i> < 0.001), low appendicular muscle mass (OR = 2.31, 95% CI: 1.44-3.73, <i>p</i> = 0.001), and low handgrip strength (OR = 1.64, 95% CI: 1.02-2.63, <i>p</i> = 0.043).<h4>Conclusion</h4>Circulating P-selectin represents a novel, independent biomarker for sarcopenia, reflecting endothelial activation and inflammatory pathways underlying muscle wasting.