Serum cartilage oligomeric matrix protein and clinical signs and symptoms of potential pre-radiographic hip and knee pathology.
OBJECTIVE
To examine the cross-sectional relationship between serum cartilage oligomeric matrix protein (COMP) and hip and knee clinical signs and symptoms in a sample of adults without radiographic hip or knee osteoarthritis (OA).


METHODS
A total of 145 persons with available sera and no evidence of radiographic hip or knee OA (Kellgren-Lawrence grade 0) were randomly selected from the Caucasian participants of the Johnston County Osteoarthritis Project. COMP was quantified by a competitive ELISA assay with a monoclonal antibody 17-C10. Hip and knee clinical signs and symptoms were assessed by physical examination and interview, and their associations with Ln COMP analysed with general linear models.


RESULTS
After adjustment for age, gender, body mass index (BMI), and other symptomatic joints, mean Ln COMP was statistically significantly higher among persons with hip-related clinical signs (P=0.018), among those with hip-related symptoms (P=0.046), and among individuals meeting American College of Rheumatology clinical criteria for hip OA (P=0.021). There were no statistically significant associations between any of the knee-related clinical signs and symptoms and Ln COMP.


CONCLUSIONS
Serum COMP may be useful as a biomarker of pre-radiographic hip joint pathology; its utility as a biomarker of pre-radiographic knee joint pathology is unclear.
Dragomir
A D
AD
Thurston Arthritis Research Center, Department of Epidemiology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599-7330, USA.
Kraus
V B
VB
Renner
J B
JB
Luta
G
G
Clark
A
A
Vilim
V
V
Hochberg
M C
MC
Helmick
C G
CG
Jordan
J M
JM
D000368:Aged; D000369:Aged, 80 and over; D064236:Cartilage Oligomeric Matrix Protein; D002358:Cartilage, Articular / Q000000981:diagnostic imaging / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D016326:Extracellular Matrix Proteins / Q000097:blood*; D005260:Female; D006023:Glycoproteins / Q000097:blood*; D006621:Hip Joint / Q000000981:diagnostic imaging / Q000473:pathology*; D006801:Humans; D007719:Knee Joint / Q000000981:diagnostic imaging / Q000473:pathology*; D008297:Male; D064235:Matrilin Proteins; D008875:Middle Aged; D011859:Radiography
D064236:Cartilage Oligomeric Matrix Protein; D016326:Extracellular Matrix Proteins; D006023:Glycoproteins; D064235:Matrilin Proteins; C577553:TSP5 protein, human