Elevated serum leptin levels are associated with low vitamin D, sarcopenic obesity, poor muscle strength, and physical performance in knee osteoarthritis

Abstract

CONTEXT: The associations between serum leptin, vitamin D status, sarcopenic obesity, muscle strength and physical performance in osteoarthritis (OA) remain uncertain. OBJECTIVE: To analyse the relationships between serum leptin, vitamin D status, muscle strength and physical performance in OA patients. METHODS: A total of 208 knee OA patients were enrolled. Serum leptin, vitamin D, muscle strength and physical performance were evaluated. RESULTS: OA patients with sarcopenic obesity had significantly higher serum leptin levels than those with non-sarcopenic obesity. In addition, knee OA patients with sarcopenic obesity displayed low grip strength and poor physical performance. Furthermore, high serum leptin was negatively associated with vitamin D and physical performance. CONCLUSIONS: Serum leptin levels were correlated with low vitamin D, reduced muscle strength and functional impairment, suggesting that serum leptin might serve as a biomarker reflecting physical performance in OA patients.