Diabetes Mellitus Type 2 and Coronary Artery Bypass Grafting: Elevated Risks of Mortality and Postoperative...

Type 2 diabetes mellitus (T2DM) has been associated with higher perioperative risks in coronary artery bypass grafting (CABG). This study examines preoperative characteristics, surgical factors, and postoperative outcomes of diabetic and nondiabetic patients undergoing CABG to identify differences in clinical profiles and complications.

A retrospective analysis was conducted on 425 patients (214 nondiabetic, 211 diabetic) using SPSS 21. Continuous variables were compared using the Student t-test, whereas categorical variables were compared using the chi-squared test.

Diabetic patients had higher BMI (30.1 vs. 28.4 kg/m², p < 0.001), worse glycemic control (HbA1c 7.9 vs. 5.6, p < 0.001), and higher rates of hypertension (84.4% vs. 62.6%, p < 0.001) and CHF (73% vs. 64%, p = 0.03). They also exhibited lower hemoglobin levels (12.8 vs. Thirteen.6 g/dL, p < 0.001), higher INR (1.0 vs. 0.9, p < 0.001), and higher rates of STEMI (13.3% vs. 5.1%, p = 0.003). Sex distribution also differed, with fewer males in the diabetic group (147 vs. 172, p = 0.007). Surgically, they required more urgent/emergent procedures (27% vs. 7.4%, p < 0.001) and longer bypass times (147.5 vs. 135.2 min, p = 0.024). Postoperatively, diabetics had higher mortality (5.2% vs. 0.5%, p = 0.003), stroke (13.3% vs. 2.8%, p < 0.001); cardiovascular events such as MI or stroke (9% vs. 0.5%, p < 0.001); infections (36.5% vs. 2.3%, p < 0.001); renal failure (20.4% vs. 2.8%, p < 0.001); gastrointestinal events (17.5% vs. 4.7%, p < 0.001); postoperative cardiac arrest (33.6% vs. 22%, p = 0.005); reoperation for bleeding (9.5% vs. 1.4%, p < 0.001); and longer hospital stays (9.2 vs. 6.3 days, p < 0.001). After adjustment for baseline demographic and clinical characteristics, diabetes mellitus was independently associated with significantly worse postoperative outcomes.

Diabetic patients undergoing CABG had worse preoperative health, challenging surgical procedures, and much worse postoperative outcomes. These findings highlight the importance of targeted perioperative interventions for reducing hazards in this high-risk population.