The relationship between serum osteopontin and disease activity in rheumatoid arthritis and the role in interstitial pulmonary fibrosis / 中华风湿病学杂志

ABSTRACT

ObjectiveTo investigate the association between serum level of osteopotin(OPN) and disease activity of rheumatoid arthritis (RA) patients, and explore the importance of OPN in the pathogenesis of interstitial lung disease (ILD) in RA. MethodsSixty-five RA patients and 20 healthy controls were pros-pectively enrolled. RA patients were divided into active group(n=43) and inactive group(n=22), and ILD groups (n=24) and non-ILD group (n=41). Enzyme-linked immunosorbent assay (ELISA) was used to detect the serum levels of OPN in patients with RA and healthy controls, and the relationship between OPN and other clinical and laboratory findings were analyzed.Results① Serum OPN tended to be significantly higher in RA patients (median, 18.0 ng/ml) than in the healthy controls (median, 14.3 ng/ml), P<0.01; ②The serum level of OPN in RA patients showed a significant positive correlation with the course of disease, numbers of tender joints , ESR and CRP, but no positive relationship was found in number of swollen joints; ③ The serum level of OPN was significantly higher in RA-ILD patients(median, 20.0 ng/ml) than that in non-lLD (median, 17.0 ng/ml, P<0.05). And there was remarkable negative correlation between the concentration of serum OPN and the value of PaO2, but no association was found with pulmonary function %VC and %DLCO. ④ Compared with the non-ILD group, the ILD group had more active disease in terms of tender joint counts and swollen joint counts, ESR, CRP(P<0.01) and the serum titer of RF-IgM,(P<0.05). ConclusionOPN plays a role in the pathogenesis of RA and is related to the disease activity. It may serve as an active disease inflammatory marker of RA . OPN may be involved in the pathogenesis of RA related ILD and is associated with the severity of pulmonary damage.