Kobayashi T, Yoshihara Y, Samura A, Yamada H, Shinmei M, Roos H, Lohmander L S
Department of Orthopaedic Surgery, National Defence Medical College, Tokorozawa, Japan.
Ann Rheum Dis. 1997 Aug;56(8):500-3. doi: 10.1136/ard.56.8.500.
To explore in a cross sectional study in patients with primary knee osteoarthritis (OA) the relations between body mass index (BMI), disease stage, and the concentrations of a putative joint fluid marker of type II collagen synthesis, procollagen II C-propeptide.
The study included 142 patients with knee OA (median age 68, median BMI 24.1). OA was staged radiologically. The concentrations in synovial fluid of procollagen II C-propeptide were measured by a sandwich enzyme immunoassay.
Joint fluid concentrations of procollagen II C-propeptide were increased in knees with OA (median 3.7 ng/ml), compared with published reference values for knees in healthy adult volunteers (median 1.3 ng/ml). The concentrations of procollagen II C-propeptide were independently related to both OA stage and BMI (r = 0.343, p < 0.0001 and r, = 0.253, p = 0.002, respectively).
Joint fluid concentrations of this putative marker of collagen II synthesis are high in early and mid-stage OA, but decrease in end stage disease. In addition and for the first time it was shown that the concentrations in synovial fluid of procollagen II C-propeptide increase with increasing BMI in primary knee OA. The increased joint fluid values of this marker in patients with primary knee OA and a high BMI, may reflect increased rates of collagen synthesis in their joint cartilage and could relate to the previously shown increased risk for disease progression in such patients.
在一项针对原发性膝骨关节炎（OA）患者的横断面研究中，探讨体重指数（BMI）、疾病阶段与一种假定的II型胶原合成关节液标志物——前胶原II C-端肽浓度之间的关系。
该研究纳入了142例膝骨关节炎患者（中位年龄68岁，中位BMI为24.1）。通过放射学方法对骨关节炎进行分期。采用夹心酶免疫分析法测定滑液中前胶原II C-端肽的浓度。
与健康成年志愿者膝关节的已发表参考值（中位值1.3 ng/ml）相比，骨关节炎膝关节中前胶原II C-端肽的关节液浓度升高（中位值3.7 ng/ml）。前胶原II C-端肽的浓度与骨关节炎阶段和BMI均独立相关（r分别为0.343，p < 0.0001和r为0.253，p = 0.002）。
这种假定的II型胶原合成标志物的关节液浓度在OA的早期和中期较高，但在终末期疾病中降低。此外，首次表明在原发性膝骨关节炎中，滑液中前胶原II C-端肽的浓度随BMI升高而增加。原发性膝骨关节炎且BMI较高的患者中该标志物的关节液值升高，可能反映其关节软骨中胶原合成速率增加，并且可能与之前显示的此类患者疾病进展风险增加有关。
