PON1 polymorphism, diabetes mellitus, obesity, and risk of myocardial infarction: Modifying effect of diabetes mellitus and obesity on the association between PON1 polymorphism and myocardial infarction

Purpose: Previous studies on PON1 gene polymorphism and the risk of coronary atherosclerotic diseases have been inconsistent. This may be in part due to population difference in prevalence of high oxidative stress and its modifying effect on the association. Diabetes and obesity are two major risk factors of myocardial infarction (MI) and associated with high oxidative stress. We investigated the association between PON1 Q192R polymorphism and the risk of myocardial infarction (MI) and in particular, whether the association can be modified by diabetes mellitus (DM) and obesity. Methods: We conducted a case-control study, including 154 MI cases and 154 controls enrolled in Beijing, China. Epidemiological and clinical data and PON1 Q192R genotype were obtained from each subject. Results: Without considering the modifying effect of DM and obesity, PON1 Q192R polymorphism was not associated with MI. When simultaneously examining the joint association of this polymorphism, DM, and obesity with MI, as compared to subjects with QQ genotypes and without DM and obesity, subjects with QR/RR genotypes and with either DM or obesity had significantly higher risk of MI (OR = 3.6, 95% Cl: 1.5-8.7). Conclusion: Our data suggest that PON1 Q192R polymorphism was not independently associated with MI but further increased the risk of MI among the subjects with DM, obesity, or both, the conditions associated with high oxidative stress.