Aims: Age is an important determinant of outcomes in patients treated with percutaneous coronary intervention (PCI). This report from the randomised multicentre SPIRIT III trial compares the outcomes in elderly and younger patients treated with everolimus-eluting stent (EES) versus paclitaxel-eluting stent (PES).
Methods and results: A total of 1,002 patients with stable or unstable angina or inducible ischaemia undergoing PCI were randomised in a 2:1 ratio to receive EES or PES. Outcomes were examined across the randomised groups as a function of age and stent type. Patients ≥65 years of age (elderly) treated with EES vs. PES had lower in-segment late lumen loss (0.11±0.32 mm vs. 0.38±0.55 mm, respectively, p=0.0002) and lower rates of binary in-segment restenosis (3.4% vs. 15.5%, p = 0.004) at eight months, along with a 48% lower incidence of 3-year target vessel failure (TVF=cardiac death, myocardial infarction and ischaemia-driven target vessel revascularisation [TVR]; 10.8% vs. 20.8%, p=0.009), mainly due to a lower incidence of TVR (5.4% vs. 9.2%, p=0.20). Among EES patients, elderly compared to younger patients had comparable rates of binary in-segment restenosis (3.4% vs. 5.6%, p=0.44) at eight months but paradoxically lower rates of TVF (10.8% vs. 17.1%, p=0.03) at three years. Among PES patients, elderly compared to younger patients had a higher rate of binary in-segment restenosis (15.5% vs. 3.4%, p=0.01) at eight months and no difference in the rate of 3-year TVF (20.8% vs. 19.4%, p=0.77) .There was a significant interaction between stent assignment, age ≥65 years and 8-month angiographic in-segment late loss (p=0.001).
Conclusions: Implantation of both EES and PES appeared to be safe in elderly patients, however EES compared to PES was more effective due to enhanced 3-year MACE- and TVF-free outcomes. Further research should clarify age-specific mechanisms of neointimal response after treatment with drug-eluting stents.