Influence of female sex on long-term mortality after acute coronary syndromes treated by percutaneous coronary intervention

Abstract

Female sex has been associated with worse outcome after percutaneous coronary intervention (PCI) for acute coronary syndromes (ACS). We assessed the influence of female sex on the long-term outcome of patients undergoing PCI for ACS. This included an unadjusted analysis and a fully-adjusted multivariate analysis including a propensity score. This was an observational cohort study involving 7304 patients who had PCI for ACS [ST-elevation myocardial infarction (STEMI), non-ST elevation (NSTE) ACS] between October 2003 and September 2010. We analysed the effect of female sex on outcome. The primary end point was all-cause mortality, which was obtained from the UK Office of National Statistics at a median follow-up of 3.2 years (IQR: 1.5-4.6). Women were significantly older and had higher rates of diabetes mellitus compared with men. Over long-term follow-up, mortality was significantly higher in women with ACS compared with men; as a whole [all ACS: odds ratio (OR) 1.351, P<0.001] or when analysed by ACS type (NSTE ACS: OR 1.260, P=0.009; STEMI: OR 1.625, P<0.001). However, after adjustment using multivariate analysis, female sex was not an independent predictor of mortality in any ACS group (all ACS: OR 0.978, P=0.772; NSTE ACS: OR 0.954, P=0.603; STEMI: OR 1.081, P=0.567). This observation remained after the incorporation of a propensity score into the multivariate analysis [OR 0.95, 95% confidence interval 0.82-1.10]. Women presenting with ACS were older and had more baseline comorbidities. Female sex, however, does not appear to be an independent risk factor for mortality in our cohort.