Comparison of drug-eluting and bare-metal stents in patients with diabetes undergoing primary percutaneous coronary intervention: what is the evidence?

A best evidence topic was written according to a structured protocol. The question addressed was, should the practising interventional cardiologist use drug-eluting stents (DESs) or bare-metal stents (BMSs) when undertaking primary percutaneous coronary intervention (PCI) in diabetic patients. The relevant outcomes that were used to determine the answer to this question included: in-stent restenosis, target vessel revascularization (TVR), mortality, myocardial infarction and in-stent thrombosis. The OVID Medline database was used to carry out the reported search for abstracts of relevant journal articles. Altogether 102 papers were found, of which 7 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. From the evidence available, we conclude that in-stent restenosis is less likely to occur over a follow-up of at least 6 months if a DES is used instead of a BMS. Furthermore, TVR is less likely to be required in diabetic patients who receive a DES in comparison with a BMS. Nevertheless, no significant difference in mortality between stents was detected by the studies reviewed. This included no difference in the incidence of cardiac and non-cardiac causes of death. There was evidence showing that DESs are associated with a decrease in the risk of myocardial infarction and, in particular, a decrease in non-Q-wave myocardial infarction. However, there was also conflicting evidence demonstrating no significant difference in the incidence of myocardial infarction between diabetic patients who had received a BMS or a DES. Moreover, the available evidence showed no significant difference in the risk of in-stent thrombosis for all DESs with the exception of Sirolimus eluting stents in which the evidence was not consistent. In summary, the available evidence supports the use of DESs over BMSs in diabetic patients undergoing primary PCI.