Comparative efficacy of coronary artery bypass surgery vs. percutaneous coronary intervention in patients with diabetes and multivessel coronary artery disease with or without chronic kidney disease

Background The optimal method of coronary revascularization among patients with diabetes mellitus (DM) and multivessel coronary artery disease (CAD) complicated by chronic kidney disease (CKD) remains unknown. Purpose To examine the impact of coronary artery bypass surgery (CABG) vs. percutaneous coronary intervention (PCI) on cardiovascular outcomes in patients with diabetes with and without CKD. Methods We conducted an 'as-treated' subgroup analysis of the FREEDOM trial to examine the therapeutic efficacy of CABG vs. PCI among patients with DM stratified by the presence (n = 451) or absence (n = 1392) of CKD. We defined CKD as an estimated glomerular filtration rate (eGFR)< 60 mL/min/1.73m(2). Baseline characteristics and clinical outcomes were compared between PCI and CABG groups within each CKD stratum. The primary endpoint was the composite occurrence of all-cause death, stroke or myocardial infarction [major adverse cardiovascular and cerebrovascular events (MACCE)]. Event rates were estimated at 5 years using the Kaplan-Meier approach and hazard ratios (HRs) for CABG (vs. PCI) were generated using Cox regression. Results Patients with CKD (mean eGFR 47 mL/min/1.73m(2)) were older and more often female compared to those without renal impairment. Over a median follow-up of 3.8 years, the effect of CABG on MACCE was consistent among those with CKD (26.0% vs. 35.6%; HR [95% CI]: 0.73 [0.50-1.05]) and without CKD (16.2% vs. 23.6%; HR [95% CI)]: 0.76 [0.58-1.00]) with no evidence of interaction (p(int) = 0.83). Stroke rates were non-significantly higher with CABG whereas rates of MI and repeat revascularization were significantly reduced with CABG in both groups. Conclusions Compared to PCI, the effects of CABG on long-term risks for MACCE observed in the FREEDOM trial are preserved among patients with mild to moderate CKD.