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.