TY - JOUR
T1 - Cartilage oligomeric matrix protein in patients with juvenile idiopathic arthritis: relation to growth and disease activity
AU - Bjørnhart, Birgitte
AU - Juul, Anders
AU - Nielsen, Susan
AU - Zak, Marek
AU - Svenningsen, Pernille
AU - Müller, Klaus
N1 - Keywords: Adult; Arthritis, Juvenile Rheumatoid; Blood Platelets; C-Reactive Protein; Cartilage, Articular; Child; Child Development; Cohort Studies; Extracellular Matrix; Extracellular Matrix Proteins; Female; Glycoproteins; Growth Disorders; Humans; Insulin-Like Growth Factor I; Male; Prognosis
PY - 2009
Y1 - 2009
N2 - OBJECTIVE: Cartilage oligomeric matrix protein (COMP) has been identified as a prognostic marker of progressive joint destruction in rheumatoid arthritis. In this population based study we evaluated associations between plasma concentrations of COMP, disease activity, and growth velocity in patients with recent-onset juvenile idiopathic arthritis (JIA). COMP levels in JIA and healthy children were compared with those in healthy adults. Plasma levels of insulin-like growth factor I (IGF-1), which has been associated with COMP expression and growth velocity, were studied in parallel. METHODS: 87 patients with JIA entered the study, including oligoarticular JIA (n = 34), enthesitis-related arthritis (n = 8), polyarticular rheumatoid factor (RF)-positive JIA (n = 2), polyarticular RF-negative JIA (n = 27), systemic JIA (n = 6), and undifferentiated JIA (n = 10). Plasma levels of COMP were measured by ELISA and IGF-1 by a radioimmunoassay. RESULTS: Significantly higher COMP levels [mean 18.9 U/l (95% CI 17.3-20.5)] were found in healthy children compared with healthy adults [mean 10.7 U/l (95% CI 9.4-12.1)] (p < 0.0001). COMP levels in the JIA patients [mean 13.5 U/l (95% CI 12.4-14.7)] were significantly reduced compared to healthy children (p < 0.0001), and correlated negatively with C-reactive protein (CRP; r = -0.29, p = 0.01) and thrombocyte count (r = -0.28, p = 0.02). COMP levels in the JIA patients correlated positively with growth velocity (cm/yr) (r = 0.38, p = 0.0003) and growth velocity (SDS) (r = 0.29, p = 0.007). CONCLUSION: We found reduced COMP levels in children with JIA compared with healthy children. COMP levels in JIA correlated negatively with inflammatory activity as evaluated by CRP and the thrombocyte counts, and were associated with reduced growth rate.
AB - OBJECTIVE: Cartilage oligomeric matrix protein (COMP) has been identified as a prognostic marker of progressive joint destruction in rheumatoid arthritis. In this population based study we evaluated associations between plasma concentrations of COMP, disease activity, and growth velocity in patients with recent-onset juvenile idiopathic arthritis (JIA). COMP levels in JIA and healthy children were compared with those in healthy adults. Plasma levels of insulin-like growth factor I (IGF-1), which has been associated with COMP expression and growth velocity, were studied in parallel. METHODS: 87 patients with JIA entered the study, including oligoarticular JIA (n = 34), enthesitis-related arthritis (n = 8), polyarticular rheumatoid factor (RF)-positive JIA (n = 2), polyarticular RF-negative JIA (n = 27), systemic JIA (n = 6), and undifferentiated JIA (n = 10). Plasma levels of COMP were measured by ELISA and IGF-1 by a radioimmunoassay. RESULTS: Significantly higher COMP levels [mean 18.9 U/l (95% CI 17.3-20.5)] were found in healthy children compared with healthy adults [mean 10.7 U/l (95% CI 9.4-12.1)] (p < 0.0001). COMP levels in the JIA patients [mean 13.5 U/l (95% CI 12.4-14.7)] were significantly reduced compared to healthy children (p < 0.0001), and correlated negatively with C-reactive protein (CRP; r = -0.29, p = 0.01) and thrombocyte count (r = -0.28, p = 0.02). COMP levels in the JIA patients correlated positively with growth velocity (cm/yr) (r = 0.38, p = 0.0003) and growth velocity (SDS) (r = 0.29, p = 0.007). CONCLUSION: We found reduced COMP levels in children with JIA compared with healthy children. COMP levels in JIA correlated negatively with inflammatory activity as evaluated by CRP and the thrombocyte counts, and were associated with reduced growth rate.
U2 - 10.3899/jrheum.080942
DO - 10.3899/jrheum.080942
M3 - Journal article
C2 - 19605679
SN - 0315-162X
VL - 36
SP - 1749
EP - 1754
JO - Journal of Rheumatology
JF - Journal of Rheumatology
IS - 8
ER -