Objective: We sought to investigate serum paraoxonase/arylesterase activities in patients with acute coronary syndromes (ACS) and their correlations with the severity and extent of coronary artery disease (CAD).
Methods and results: Three groups of patients were investigated: 89 patients with ACS, 54 patients with normal coronary angiograms (no-CAD group), and 27 healthy comparison subjects. ACS patients were divided into three groups according to their clinical presentation: unstable angina pectoris (UAP, Braunwald III-B, n = 31), non-ST elevation myocardial infarction (NSTEMI) (n = 27), and ST-elevation myocardial infarction (STEMI) (n = 31). Serum paraoxonase/arylesterase activities were measured spectrophotometrically. Angiographic CAD extent was expressed both by the number of vessels diseased and by the Gensini scoring system. Results showed that serum paraoxonase/ arylesterase activities and the paraoxonase/high density lipoprotein-cholesterol (HDL-C) ratio were significantly lower in the STEMI, NSTEMI, UAP groups than in no-CAD and control groups. Serum paraoxonase/arylesterase activities and paraoxonase/HDL-C ratio were reduced in patients with 2-vessel disease (VD) and 3-VD compared to the I-VD and no-CAD group (P < 0.001). In patients with ACS, the Gensini score correlated inversely with serum paraoxonase (r = -0.419, P < 0.001), arylesterase (r = -0.492, P < 0.0001), and the paraoxonase/HDL-C ratio (r = -0.377, P < 0.001). Serum arylesterase (r = 0.161, P = 0.03) and paraoxonase (r = 0.135, P = 0.002) activities were positively correlated with HDL-C levels. Serum arylesterase activity (P < 0.0001), gender (P = 0.0037), diabetes mellitus (P = 0.005) and LDL-C levels (P = 0.03) were independent predictors of CAD presence.
Conclusions: Serum paraoxonase/arylesterase activities are reduced in ACS patients and inversely correlated with the severity of CAD.