Impact of diabetes on five-year outcomes after vein graft interventions performed prior to the drug-eluting stent era.

OBJECTIVE: The aim of this study was to evaluate the differences in 5-year outcomes among diabetic and nondiabetic patients undergoing saphenous vein graft (SVG) percutaneous coronary intervention (PCI) prior to the era of distal protection and drug-eluting stents.

BACKGROUND: PCI of native coronary arteries is known to be associated with higher rates of adverse outcomes in diabetic patients compared to nondiabetic patients. However, the impact of diabetes on long-term outcomes after SVG interventions is not as well established. We conducted an evaluation of 5-year outcomes after SVG PCI in the two decades prior to the availability of distal protection devices and drug-eluting stents.

METHODS: Data on 2,556 subjects (1,780 nondiabetic and 776 diabetic) undergoing SVG PCI at Emory Hospital from 1981 to 2001 were collected and entered into a computerized database and analyzed for adverse cardiovascular outcomes.

RESULTS: Compared to the nondiabetic group, the diabetic group had worse 1-year (87.7% vs. 94.9%; p < 0.0001) and 5-year survival rates (62.9% vs. 78.5%; p < 0.0001). In the subset of patients receiving stents, 5-year survival remained significantly worse in the diabetic group (78.2% vs. 87.1%; p = 0.009). After multivariate analysis, diabetes was an independent predictor of 5-year mortality (hazard ratio = 1.8; 95% CI = 1.5-2.5; p < 0.0001).

CONCLUSION: Diabetic patients undergoing vein graft PCI prior to the distal protection and drug-eluting stent era had significantly worse long-term outcomes compared to nondiabetic patients. The effect on long-term outcomes using these newer devices in diabetic subjects undergoing SVG PCI must be established for a true assessment of their impact.