Improved two-year outcomes after drug-eluting versus bare-metal stent implantation in women and men with large coronary arteries: importance of vessel size.

Objectives: To investigate the importance of vessel size on outcome differences by comparing the effects of drug-eluting stents (DES) versus bare-metal stents (BMS) in women and men with large coronary vessels.

Methods: All 2314 BASKET-PROVE patients randomized to DES versus BMS were followed for 2 years with a primary endpoint of major adverse cardiac events (MACE: cardiac death, non-fatal myocardial infarction, target-vessel revascularization). Cox proportional hazard models were used to evaluate the relative risk for women and men, respectively. All comparisons were adjusted for vessel size.

Results: Age, risk factors and complexity of coronary artery disease differed between women and men. DES reduced MACE rates at 2 years compared to BMS--in women: 4% vs. 15%, p<0.0001 with a hazard ratio (HR) of 0.27 (0.15-0.51), and men: 6% vs. 10%, p=0.003 (HR=0.60 (0.43-0.84)), respectively. The association persisted in both women (HR=0.25 (0.13-0.46)) and men (HR=0.60 (0.42-0.84)) following multivariable adjustments. A significant gender-treatment interaction was present (p=0.02). The reduced risk of MACE following DES vs. BMS implantation was present until 6 months in both women (HR=0.15 (0.06-0.36)) and men (HR=0.32 (0.17-0.59)) and remained significant until 2 years in women (HR=0.36 (0.15-0.87)), but not in men (HR=0.87 (0.49-1.55)).

Conclusions: In women and men with similarly sized large coronary arteries, DES reduced 2-year MACE rates compared to BMS, but the significant gender-treatment interaction indicated a greater benefit of DES in women. Thus, factors other than vessel size seem to determine this gender difference.