Association between serum cartilage oligomeric matrix protein and coronary artery calcification in maintenance hemodialysis patients

Background Coronary artery calcification (CAC) is common in end-stage renal disease (ESRD) patients, and the extent of CAC is closely related to cardiovascular outcomes in ESRD patients. Cartilage oligomeric matrix protein (COMP), as a component of the vascular matrix, has been found to be an inhibitor of arterial calcification in basic studies. However, there is no clinical research on the correlation between COMP and CAC in maintenance hemodialysis (MHD) patients. The aim of this study was to explore the relationship between serum COMP levels and CAC and cardiovascular events in MHD patients. Methods Serum COMP levels were compared between 54 MHD patients and 66 healthy people. MHD patients were then divided into three groups according to the tertiles of the concentration of COMP level and were followed up for major adverse cardiac events (MACEs), which were defined as a combined end point of new onset angina pectoris, nonfatal myocardial infarction, heart failure, coronary artery revascularization, hospitalization due to angina pectoris and all-cause deaths. The CAC score was calculated based on computed tomography scans. Results The serum COMP level in MHD patients was significantly higher than that in the general population 984.23 (248.43–1902.61) ng/mL vs. 219.01 (97.26–821.92) ng/mL, P r = 0.313, P = 0.021) and serum parathyroid hormone in MHD patients (r = 0.359, P β = 0.424, t = 3.130, P P = 0.030, 95% CI: 0.526–0.882. After a median follow-up of 16 months (8–24 months), there was no difference in the incidence rate of MACEs between the upper, middle and lower serum COMP groups. Conclusions Our study found that MHD patients have higher levels of circulating COMP than controls. The serum COMP level is positively correlated with CAC score and could be used as a biomarker of severe CAC in MHD patients. However, there is no obvious correlation between serum COMP levels and the incidence of cardiovascular events.