title: Elevated serum leptin levels are associated with low vitamin D, sarcopenic obesity, poor muscle strength, and physical performance in knee osteoarthritis.
abstract: BACKGROUND
  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.
authors.affiliation: a Department of Biochemistry, Faculty of Medicine , Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society , Bangkok , Thailand.
authors.forename: Pacharee
authors.initials: P
authors.lastname: Manoy
authors.affiliation: a Department of Biochemistry, Faculty of Medicine , Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society , Bangkok , Thailand.
authors.forename: Wilai
authors.initials: W
authors.lastname: Anomasiri
authors.affiliation: b Department of Orthopaedics, Faculty of Medicine , Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society , Bangkok , Thailand.
authors.forename: Pongsak
authors.initials: P
authors.lastname: Yuktanandana
authors.affiliation: b Department of Orthopaedics, Faculty of Medicine , Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society , Bangkok , Thailand.
authors.forename: Aree
authors.initials: A
authors.lastname: Tanavalee
authors.affiliation: b Department of Orthopaedics, Faculty of Medicine , Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society , Bangkok , Thailand.
authors.forename: Srihatach
authors.initials: S
authors.lastname: Ngarmukos
authors.affiliation: b Department of Orthopaedics, Faculty of Medicine , Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society , Bangkok , Thailand.
authors.forename: Thanathep
authors.initials: T
authors.lastname: Tanpowpong
authors.affiliation: a Department of Biochemistry, Faculty of Medicine , Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society , Bangkok , Thailand.|b Department of Orthopaedics, Faculty of Medicine , Chulalongkorn University, King Chulalongkorn Memorial Hospital, Thai Red Cross Society , Bangkok , Thailand.
authors.forename: Sittisak
authors.initials: S
authors.lastname: Honsawek
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D005260:Female; D006801:Humans; D020738:Leptin / Q000097:blood*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D053580:Muscle Strength / Q000502:physiology*; D009765:Obesity / Q000097:blood* / Q000503:physiopathology; D020370:Osteoarthritis, Knee / Q000097:blood* / Q000503:physiopathology; D010809:Physical Fitness / Q000502:physiology*; D055948:Sarcopenia / Q000097:blood / Q000503:physiopathology; D014807:Vitamin D / Q000097:blood*
chemical_list: D015415:Biomarkers; D020738:Leptin; D014807:Vitamin D
keywords: Leptin; muscle strength; osteoarthritis; physical performance; sarcopenic obesity; vitamin D