IntroductionSerum paraoxonase 1 (PON1) is now known to be related to cardiovascular diseases (CVD). The aim of this study was to determine the relationship between PON1 concentration and high-density lipoprotein (HDL) subclasses in patients with proven CVD, cardiovascular risk factors but no CVD (CRF), and in healthy controls (control group).Material and methodsA case-control study was carried out with 69 volunteers from the Mexican Institute of Social Security, Mexico. Clinical parameters, lipid profile, PON1 concentration, PON1 activities (AREase and CMPAase), and HDL subclasses were evaluated.ResultsPatients with CVD had significantly higher glucose and lower total cholesterol than the control group had (p < 0.01). AREase activity was not different between the control (122.57 ±30.72 U/ml), CRF (115.81 ±32.81 U/ml), and CVD (109.34 ±29.60 U/ml) groups. PON1 concentration was significantly lower in CVD patients than in CRF and control patients (p < 0.001); a positive correlation was observed between AREase activity and PON1 concentration in the CVD group (Rho = 0.58; p < 0.01). Logistic regression analysis showed that the decrease in PON1 level was associated with the CVD group (RRR = 0.20; 95% CI: 0.09–0.45) but not with the CRF group (RRR = 1.29; 95% CI: 0.89–1.90). Significant differences were observed in HDL 2a and HDL 3a concentrations between the control group and CRF and CVD groups (p < 0.05), but not between the CRF and CVD groups.ConclusionsOur data suggest that PON1 status and HDL characteristics could be early biomarkers that predict the potential for developing CVD.