We investigated the possible association between insulin receptor substrate-1 (IRS-1) polymorphisms and high platelet reactivity in coronary artery disease (CAD) patients with type 2 diabetes mellitus (T2DM).
The AA (homozygous Arg972 IRS1) and GA (heterozygous Arg972 IRS1) genotypes were associated with an increased risk of AD after adjustment for comorbidities including type 2 diabetes mellitus, coronary heart disease, and hypertension (p<0.001; adjusted odds ratio [OR] 3.93 and 2.90, respectively).
The insulin receptor substrate-1 (IRS1) gene is considered a major T2DM gene, and common genetic variations near the IRS1 gene were found to be associated with T2DM, insulin resistance, adiposity, and CAD.
Although IR and T2D may be mechanistically linked to CAD via subclinical atherosclerosis, an alternate mechanism for the IR-T2D-CAD associations at 2q36.3-IRS1 must be postulated.
Notably, the body-fat-decreasing allele near IRS1 is associated with decreased IRS1 expression and with an impaired metabolic profile, including an increased visceral to subcutaneous fat ratio, insulin resistance, dyslipidemia, risk of diabetes and coronary artery disease and decreased adiponectin levels.
The association between IRS-1 genetic variants, platelet function, and the risk of major adverse cardiac events (MACE) at 2 years was assessed in 187 patients with type 2 DM and stable coronary artery disease on maintenance aspirin and clopidogrel therapy.
Besides the increased frequency of diabetes, carriers showed a more atherogenic lipid profile, suggesting a potential role of the IRS-1 gene in the pathogenesis of lipid abnormalities associated with CAD.
Besides the increased frequency of diabetes, carriers showed a more atherogenic lipid profile, suggesting a potential role of the IRS-1 gene in the pathogenesis of lipid abnormalities associated with CAD.