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

AIM: 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. METHODS: 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. RESULTS: 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]. CONCLUSION: 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.