Serum Paraoxonase Activity in Patients with Ischaemic and Nonischaemic Dilated Cardiomyopathy.

Background: This study examined whether the serum PON1 activity is different in patients with ischaemic dilated cardiomyopathy (IDCM) and nonischaemic dilated cardiomyopathy (NDCM) and the relation between the serum PON1 activity and serum pro-BNP levels. Methods and results: In this study, we enrolled 60 patients with left ventricular systolic failure (New York Heart Association [NYHA] class III-IV) and a left ventricular ejection fraction (EF) < 40% as determined by echocardiography and 30 healthy subjects. The patients with systolic heart failure were divided into two groups: patients with IDCM and patients with NDCM. Blood samples were obtained to measure the serum PON1 activity and the serum pro-BNP levels. The median serum PON1 activities were lower among the patients with IDCM or with NDCM compared with the control subjects (p <.001, p = .043, respectively). Compared with the control subjects, the patients with IDCM or with NDCM had higher serum pro-BNP levels (p < .001, p < .001, respectively). The serum PON1 activity was negatively correlated with the serum pro-BNP levels in patients with IDCM (r = -0.548, p < .001). The area under the ROC curve of the serum PON1 activity was 0.798. Using a serum PON1 activity of 201.3 U/L as a cut-off value, the sensitivity was 86.84% and specificity was 66.67% for the diagnosis of IDCM. Conclusions: In this study, the serum PON1 activity was significantly reduced in the patients with IDCM or with NDCM compared with the control subjects. The serum PON1 activity of the patients with IDCM was negatively correlated with the serum pro-BNP levels.