Gender related survival differences in ST-elevation myocardial infarction patients treated with primary PCI

Abstract

Background: Data about gender as an independent risk factor for death in ST-elevation myocardial infarction (STEMI) patients is still contrasting. Aim was to assess how gender influences in-hospital and long-term all-cause mortality in STEMI patients with primary percutaneous coronary intervention (PCI) in our region. Methods: We analysed data from 2069 STEMI patients undergoing primary PCI in our institution from January 2009–December 2014, of whom 28.9% were women. In-hospital and long-term mortality were observed in women and men. The effect of gender on in-hospital mortality was assessed by binary logistic regression modelling and by Cox regression analysis for long-term mortality. Results: Women were older (68.3±61.8 vs 61.8±12.0 years; p<0.0001), with a higher prevalence of diabetes (13.7% vs 9.9%; p=0.013) and tend to be more frequently admitted in cardiogenic shock (8.4% vs 6.3%; p =0.085). They were less frequently treated with bivalirudin (15.9% vs 20.3%; p=0.022). In-hospital mortality was higher among women (14.2% vs 7.8%; p<0.0001). After adjustment, age (adjusted OR: 1.05; 95% CI: 1.03 to 1.08; p < 0.001) and cardiogenic shock at admission (adjusted OR: 24.56; 95% CI: 11.98 to 50.35; p < 0.001), but not sex (adjusted OR: 1.47; 95% CI: 0.80 to 2.71) were identified as prognostic factors of in-hospital mortality. During the median follow-up of 27 months (25th, 75th percentile: 9, 48) the mortality rate (23.6% vs 15.1%; p<0.0001) was significantly higher in women. The multivariate adjusted Cox regression model identified age (HR 1.05; 95% CI 1.04–1.07; p<0.0001), cardiogenic shock at admission (HR 6.09; 95% CI 3.78–9.81; p<0.0001), hypertension (HR 1.49; 95% CI 1.02–2.18; p<0.046), but not sex (HR 1.04; 95% CI 0.74–1.47) as independent prognostic factors of follow-up mortality. Conclusion: Older age and worse clinical presentation rather than gender may explain the higher mortality rate in women with STEMI undergoing primary PCI.