RESUMO
BACKGROUND: Oxidation and inflammation are linked processes playing an important role in the development and progression of coronary artery disease (CAD). The relation between oxidation and inflammation markers with myocardial ischemia is still controversial. We assessed the association between paraoxonase (PON) polymorphisms (rs854560, rs662, rs7493) and high sensitivity C-reactive protein levels with stress-induced ischemia in patients with suspected CAD. MATERIALS AND METHODS: Patients (n = 203; 78 men; mean age 59 ± 10 years), with suspected CAD underwent on the same day stress/rest Tc-99m sestamibi cardiac single-photon emission computed tomography and venous blood samples collection, to assess PON polymorphisms, lipid profile and high sensitivity C-reactive protein levels. RESULTS: At cardiac tomography, 43 (21%) patients had stress-induced myocardial ischemia and 160 (79%) did not. At logistic regression analysis, diabetes (p < 0.005), sex (p = 0.020) and high-density lipoprotein (HDL)-cholesterol levels (p < 0.050) were independently associated with stress-induced ischemia. No differences of PON1 and PON2 genotype frequencies were observed between patients with and without stress-induced ischemia. Multiple linear regression analysis showed that LL genotype for PON1 (p < 0.03), high body mass index (BMI) values (p < 0.001) and low HDL-cholesterol levels (p < 0.05) are associated with high C-reactive protein levels independently from presence of stress-induced ischemia, age, sex, diabetes, hypertension, statin therapy, smoking and total cholesterol levels. CONCLUSIONS: The results of this study identified a weak association between the M55L polymorphism in PON1 gene and C-reactive protein levels. BMI showed a major role in the determination of C-reactive protein levels. No association between PON polymorphisms and stress-induced ischemia was found.