Estimated glucose disposal rate and long-term survival in type 2 diabetes after coronary artery bypass grafting

We performed a nationwide population-based cohort study to investigate the association between estimated glucose disposal rate (eGDR) and long-term survival after coronary artery bypass grafting (CABG) in patients with type 2 diabetes. All patients who underwent primary CABG in Sweden from 2006 to 2013 were identified from the SWEDEHEART register and by record linkage to the National Diabetes Register; all patients with type 2 diabetes were included and formed the study population. Patients were followed until 2013 through national registers for major adverse cardiovascular events and death from any cause. eGDR was calculated using waist circumference, hemoglobin A1c, and presence or the absence of hypertension. The association between eGDR and death was estimated using multivariable Cox regression. A total of 3256 patients were included. During a mean follow-up of 3.1 years (10,227 person-years), in total, 14 % patients died: 17 % (n = 186) in the 1st tertile (lowest eGDR), 14 % (n = 145) in the 2nd tertile, and 13 % (n = 133) in the 3rd tertile (highest eGDR). There was a significant association between eGDR and increased risk of death: adjusted hazard ratio (95 % confidence interval): 1.46 (1.12–1.90) for the 1st eGDR tertile compared to the 3rd and highest eGDR tertile. In conclusion, patients with type 2 diabetes who underwent CABG, a low eGDR, were associated with an increased risk of long-term all-cause mortality that was independent of other cardiovascular and metabolic risk factors. Insulin resistance measured by eGDR could be a useful risk marker in patients with type 2 diabetes and ischemic heart disease.