Short-term outcomes following coronary artery bypass graft surgery in insulin treated and non-insulin treated diabetes: A tertiary hospital experience

BACKGROUND AND AIMS: Outcomes after coronary artery bypass graft (CABG) surgery have improved due to advances in surgical technique and post-operative care. We aimed to describe contemporary clinical characteristics and short-term post-operative outcomes in diabetic patients undergoing CABG surgery. METHODS: A retrospective analysis of patients who underwent CABG surgery over a 4.5-year period in a Western Australian tertiary hospital was performed in September 2019. The cohort was stratified according to pre-operative diabetes status. RESULTS: A total of 1327 patients underwent CABG surgery, of which 572 (43.1%) had diabetes. Diabetic patients were more likely to be female (24.7% vs. 13.9%, p < 0.001) and have dyslipidaemia (83.0% vs. 68.1%, p < 0.001), hypertension (82.0% vs. 68.7%, p < 0.001), raised body mass index (29.8 ± 5.6 vs. 28.7 ± 5.1 kg/m2, p < 0.001), prior myocardial infarction (62.8% vs. 54.8%, p = 0.004), prior stroke (8.6% vs. 5.0%, p = 0.010), congestive cardiac failure (20.2% vs. 15.1%, p = 0.014), reduced estimated glomerular filtration rate (86.7 ± 36.1 vs. 90.8 ± 32.1 ml/min/1.73 m2, p = 0.036) and three-vessel coronary artery disease (74.8% vs. 67.3%, p = 0.003). Post-operative wound infections (3.1% vs. 1.5%, p = 0.022), new dialysis requirement (2.9% vs. 1.0%, p = 0.009) and 30-day hospital admission (13.1% vs. 8.5%, p = 0.007) was more likely in diabetic patients, but not myocardial infarction (3.0% vs. 2.0%, p = 0.247), stroke (1.4% vs. 0.8%, p = 0.286) or 30-day mortality (2.4% vs. 1.7%, p = 0.354). No significant differences were detected in short-term outcomes between patients with non-insulin (n = 398) versus insulin treated (n = 174) diabetes. CONCLUSIONS: Diabetic patients continue to represent a higher-risk cohort, highlighting the need for further strategies to reduce short-term adverse outcomes following CABG surgery.