Early and Late Outcomes of CABG in Diabetic Patients

Objective: To compare outcomes as well as long-term survival in patients undergoing isolated coronary artery bypass surgery in an attempt to determine the effect of diabetes mellitus on survival.

Methods: We screened our database to identify all patients who underwent isolated coronary artery bypass between 2001 and 2016. Data were collected prospectively on the index admission. Long-term survival data were obtained from the ministry of interior.

Results: There were 4409 patients, 1778 (40%) were diabetics. Diabetic patients were older (p<0.0001), had a higher incidence of co-morbidity (p<0.0001), congestive heart failure (p<0.0001), and higher EuroSCORE (p<0.0001). They had a higher incidence of left ventricular dysfunction (p=0.0007) and significant mitral regurgitation (p=0.0007). After surgery they suffered a higher incidence of major infection (p<0.0001), stroke (p<0.0001), and acute kidney injury (p=0.003). In non-diabetics and diabetics respectively, operative mortality was 77(2.9%) and 63(3.5%) (p=0.25). Late survival was reduced in the diabetic patients (p<0.0001) (figure 1). Predictors of reduced survival were age, peripheral vascular disease, CHF, reduced LV function, EuroSCORE, and diabetes mellitus (p<0.0001) as well as insulin therapy (p=0.0008).

Conclusions: After coronary artery bypass surgery diabetic patients develop a higher incidence of adverse events. While operative mortality is similar, long-term survival is reduced in diabetics. The presence of diabetes mellitus in general and insulin therapy in particular emerged as independent negative predictors of survival.