Effect of Diabetes Mellitus on Five-Year Clinical Outcomes After Single-Vessel Coronary Stenting (a Pooled Analysis of Coronary Stent Clinical Trials)

Diabetes mellitus (DM) increases the risk of clinically driven, repeat revascularization of the stented lesion in the first year after coronary stenting. The effect of DM on the risk of repeat revascularization of the stented lesion beyond 1 year, revascularization at other coronary sites, and clinical outcomes of cardiac death and myocardial infarction (MI) has not been reported. We pooled primary data from 4 multicenter trials of second-generation coronary stents that included 1,228 patients, 263 of whom (21%) had DM. Patients were followed annually to assess for prespecified end points, including repeat revascularization procedures, death, or MI. Repeat revascularization of the stented lesion was performed more frequently during the first year in patients with DM (16.0% vs 10.9%, p = 0.01) but decreased to a low frequency (1.8% vs 1.3% per year) thereafter in patients with and without DM. Repeat revascularization of other coronary segments was more frequent in patients with DM during the first and subsequent years (5-year rates, 32.2% vs 24.1%, p = 0.005). Cardiac death or MI was also more frequent among patients with DM (5-year rates, 25.4% vs 17.9%, p = 0.008) and remained significant after adjustment for all differences in baseline characteristics (hazard ratio 1.5, 95% confidence interval 1.1 to 2.0, p = 0.01). In conclusion, diabetic patients are at increased risk for revascularization of the stented lesion only in the first year after single-lesion stenting but are at increased risk for other clinical events, including cardiac death and MI, over the next 4 years.