Is the advantage of coronary bypass graft surgery over percutaneous coronary intervention in diabetic patients with severe multivessel disease influenced by the status of insulin requirement?

Several studies have shown that coronary artery bypass graft surgery (CABG) is superior to percutaneous coronary intervention (PCI) in patients with diabetes and multi-vessel disease. Whether this advantage of CABG over PCI is confined to diabetics who require insulin is unknown. We review the published literature comparing CABG with PCI in diabetics including 8 cohorts and 4,786 patients. There was a lower rate for all-cause mortality (Relative risk (RR): 0.78, 95% confidence interval (CI): 0.62-0.99), and for major adverse cardiac and cerebrovascular events (MACCE, RR: 0.59, 95% CI: 0.47-0.75) for CABG compared to PCI. Composite outcome of mortality, myocardial infarction and stoke was similar between CABG and PCI (RR: 0.87, 95% CI: 0.54-1.42). Visual inspection of the forest plots showed that in most analyses, the point estimates of the RR are similar between the insulin requiring group and non-insulin requiring group. On meta-regression, there was no interaction between status of insulin requirement and revascularization strategies (P > 0.05 for all). The presented data on the still unpublished analysis of the FREEDOM trial showed similar results. Thus, in the current era, CABG is superior to PCI with lower mortality and MACCE rates, but the state of insulin requirement had no effect on the outcomes from the two revascularization strategies.