High serum levels of rheumatoid factor and anti-phosphatidylserine antibody in patients with ischemic heart disease.

BACKGROUND Immunopathological and inflammatory processes play important roles in the initiation and development of Ischemic Heart Disease (IHD). OBJECTIVE The aim of this study was to evaluate the serum levels of several autoantibodies including rheumatoid factor (RF), anti-nuclear antibodies (ANA), anti-small nuclear ribonucleoprotein (anti-Sm), anti-phosphatidylserine (anti-PS) and anti-cardiolipin (anti-CL) antibodies in patients with IHD. METHODS A total of 120 patients with IHD with acute myocardial infarction (AMI; n=60) or unstable angina (UA; n=60) and 60 sex- and age-matched healthy subjects were enrolled in this study. Serum samples of participants were tested for the ANA, anti-Sm, anti-PS and anti-CL antibodies by ELISA. Serum level of RF was measured by a turbidometric method. RESULTS The mean serum levels of RF and anti-PS antibodies in AMI group and UA group were significantly higher than those observed in the control group (p<0.0001). The mean serum levels of RF and anti-PS antibodies in AMI patients were significantly higher than the UA group (p<0.01 and p<0.001, respectively). The mean serum levels of RF in men with AMI or UA diseases were significantly higher as compared to healthy control men (p<0.0001 and p<0.003, respectively). The differences of the serum levels of ANA, anti-Sm and anti-CL antibodies were not significant between AMI, UA and the control groups. There was no difference in the serum levels of RF, ANA, anti-Sm, anti-PS or anti-CL antibodies in patients with traditional risk factors, including hypertension, dyslipidemia, diabetes and smoking, and those without a certain risk factor. CONCLUSION Higher serum levels of RF and anti-PS antibody in patients with IHD may be considered as independent risk factors for IHD.