Association between insulin resistance indices and perioperative functional status and immediate prognosis in patients with carbohydrate metabolism disorders undergoing coronary artery bypass grafting

Highlights. Patients with coronary artery disease undergoing coronary artery bypass grafting have a high prevalence of type 2 diabetes mellitus and prediabetes. The frequency of postoperative stroke and hospital stay is significantly higher in patients with impaired carbohydrate metabolism. Insulin resistance markers are associated with a variety of perioperative characteristics, but according to multivariate analysis, only free fatty acids and HOMA-IR were independent predictors of hospitalacquired complications and long-term hospital stay Aim. To analyze insulin resistance markers and their association with the preoperative outcome and in-hospital complications of coronary bypass grafting (CABG) in patients with type 2 diabetes mellitus (DM 2), prediabetes and normoglycemia. Methods. The study included 383 consecutive patients undergoing CABG at the same center. Glycemic status, free fatty acids (FFA), fasting insulin, glucose, lipid profile of all patients were determined before surgery and the following insulin resistance indices (IR) were calculated: HOMA-IR (Homeostasis Model Assessment of Insulin Resistance), QUICKI (Quantitative Insulin Sensitivity Check Index), Revised QUICKI, McAuley. Patients were divided into 2 groups: the group that included patients with carbohydrate metabolism disorders (CMD), type 2 diabetes mellitus and prediabetes (n = 192), and the group of patients without CMD (n = 191). Perioperative characteristics of patients, postoperative complications and their association with insulin resistance markers were analyzed. Results. FFA and calculated indices of insulin resistance such as HOMA-IR, QUICKI, RevisedQUICKI, and McAuley correlated with the following perioperative characteristics: the duration of surgical intervention and cardiopulmonary bypass, lipid levels, coagulation index, left ventricular dimension and myocardial diastolic function, etc. The analysis of in-hospital complications revealed that the frequency of postoperative stroke (p = 0.044) and hospital stay after CABG >30 days (p = 0.014) was significantly higher in patients with CMD. According to the results of multivariate analysis, the predictors of the composite endpoint (hospital stay after CABG>10 days and/or significant perioperative complication) were as follows: female sex (odds ratio (OR) 2.862, 95% confidence interval (CI) 1.062-7.712, p = 0.036); age (OR 1.085, 95%CI 1.027–1.147, p = 0.003); duration of cardiopulmonary bypass (OR 1.146, 95%CI 1.008–1.301, p = 0.035); body mass index (OR 1.125, 95% CI 1.035–1.222, p = 0.005), left atrial dimension (OR 5.916 95% CI 2.188–15.996, p<0.001); any CMD (OR 1.436, 95%CI 1.029–2.003, p = 0.032), type 2 DM (OR 2.184, 95%CI 1.087–4.389, p = 0.027), FFA levels (OR 5.707, 95%CI 1.183–27.537, p = 0.029) and HOMA–IR index (OR 1.164, 95%CI 1.025–1.322, p = 0.019). Conclusion. FFA, HOMA-IR, QUICKI, Revised-QUICKI, and McAuley correlate with a variety of perioperative characteristics of patients undergoing CABG, but multivariate analysis revealed that only FFA levels and the HOMA-IR can be used as predictors of in-hospital complications and prolonged hospital stay.