Abstract 202: Insulin Resistance as an Independent Predictor of Atherosclerosis Burden in Nondiabetic Patients with Acute Myocardial Infarction
Introduction: Experimental evidence suggests that insulin resistance (IR) is a major risk factor for accelerated atherosclerosis through indirect effects on systemic risk factors and direct effects on insulin signaling in vascular endothelium and plaque macrophages.
Hypothesis: IR in persons without diabetes mellitus is associated with multi-vessel coronary artery disease (CAD) in acute myocardial infarction (AMI) patients.
Methods: We examined 1111 non-diabetic AMI patients (HbA1c ≤ 6.5) enrolled in the multicenter TRIUMPH (years 2004-2008) registry. IR was estimated using the homeostasis model assessment of IR (HOMA-IR: fasting insulin (mU/l) x fasting blood glucose (mmol/l)]/22.5). The primary outcome was the extent of angiographic atherosclerosis (≤1-vessel vs. multi-vessel disease). Modified Poisson regression models were used to examine the association between IR and multi-vessel CAD.
Results: Subjects were divided into quartiles based on HOMA-IR values (quartile 1: male <=1.35, female <=1.26; quartile 4: male >4.00, female >3.64). After adjusting for age, sex, hypertension, smoking, family history of CAD, LDL, HDL, and body mass index (BMI), IR was independently associated with multi-vessel CAD (Figure). As compared to the lowest quartile of IR, the highest quartile had more multi-vessel CAD [RR (95% CI)- 1.35 (1.11-1.64)].
Conclusion: In a large cohort of non-diabetic AMI patients, IR was associated with more advanced, multi-vessel CAD, independent of lipid levels and other components of the metabolic syndrome. This association is consistent with established experimental evidence and supports IR as a potential target for preventing atherosclerosis.
- © 2012 by American Heart Association, Inc.