title: Reference intervals of serum hyaluronic acid corresponding to the radiographic severity of knee osteoarthritis in women.
abstract: BACKGROUND
  While serum levels of hyarulonic acid (sHA) is known to be useful for a burden of disease biomarker in knee OA, it is far from practical. The reference intervals must be established for biomarkers to be useful for clinical interpretation. The aim of this study was to establish the reference intervals of sHA corresponding to the radiographic severity of knee OA for elucidating whether sHA can be useful as a burden of disease marker for individual patient with knee OA.
  
  
  METHODS
  372 women with Kellgren & Lawrence grade (K/L) 1 through 4 painful knee OA were enrolled in this study. The patients included 54 with K/L 1, 96 with K/L 2, 97 with K/L 3, and 118 with K/L 4. Serum samples were obtained from all subjects on the day that radiographs taken. A HA binding protein based latex agglutination assay that employed an ELISA format was used to measure sHA. Age and BMI adjusted one way ANOVA was used to set the reference intervals of sHA.
  
  
  RESULTS
  The reference intervals for sHA corresponding to the patients with K/L 4 (49.6 - 66.5 ng/ml) was established without any overlap against to those with K/L 1, 2 and 3, while those with K/L 1, 2 and 3 showed considerable overlap.
  
  
  CONCLUSIONS
  These results indicate that sHA can be available as a burden of disease marker for the individuals with severe knee OA (K/L 4), while it is not for those with primary to moderate knee OA (K/L 1-3).
authors: Department of Medicine for Orthopaedics and Motor Organ, Juntendo University Graduate School of Medicine, Tokyo, Japan.
authors: Haruka
authors: H
authors: Kaneko
authors: Muneaki
authors: M
authors: Ishijima
authors: Tokuhide
authors: T
authors: Doi
authors: Ippei
authors: I
authors: Futami
authors: Lizu
authors: L
authors: Liu
authors: Ryo
authors: R
authors: Sadatsuki
authors: Anwarjan
authors: A
authors: Yusup
authors: Shinnosuke
authors: S
authors: Hada
authors: Mitsuaki
authors: M
authors: Kubota
authors: Takayuki
authors: T
authors: Kawasaki
authors: Yoshitomo
authors: Y
authors: Saita
authors: Yuji
authors: Y
authors: Takazawa
authors: Hiroshi
authors: H
authors: Ikeda
authors: Hisashi
authors: H
authors: Kurosawa
authors: Kazuo
authors: K
authors: Kaneko
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D004797:Enzyme-Linked Immunosorbent Assay / Q000592:standards*; D005260:Female; D006801:Humans; D006820:Hyaluronic Acid / Q000097:blood*; D007719:Knee Joint / Q000000981:diagnostic imaging* / Q000378:metabolism*; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000097:blood / Q000175:diagnosis* / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D011446:Prospective Studies; D011859:Radiography; D012016:Reference Values; D012720:Severity of Illness Index
chemical_list: D015415:Biomarkers; D006820:Hyaluronic Acid