Risk factors for adverse outcomes of patients with acute coronary syndrome: single-centre experience with long-term follow-up of treated patients

BACKGROUND: For patients experiencing an acute coronary syndrome (ACS), a crucial time to assess their prognosis and to plan management is at discharge from hospital. AIM: The aim of the study was to identify risk factors of mortality during post-discharge period following a hospitalisation for ACS. METHODS: We studied 672 consecutive ACS patients hospitalised and discharged alive between 2002 and 2004. The analysis was done with respect to the type of ACS, i.e. unstable angina/non-ST-segment elevation myocardial infraction (UA/NSTEMI; n = 255) vs. ST-segment elevation myocardial infarction (STEMI; n = 417). All patients underwent coronary angiography and, if indicated, primary angioplasty (STEMI: 417 patients; UA/NSTEMI: 157 patients). The Cox proportional hazards regression model was used to evaluate the independent effect of the risk factors on the occurrence of primary endpoint, i.e. all-cause mortality during six-year follow-up. Survival status and date of death were obtained from the National Registry of Population (PESEL database). RESULTS: A total of 123 patients (18.3%) died within the post-discharge period. The multivariate analysis identified 11 highly significant independent predictors of mortality (in order of predictive strength): diabetes mellitus (all types), higher creatinine level, older age, and more frequent occurrence of: supraventricular arrhythmias during hospitalisation, peripheral artery disease, recurrent angina pectoris with documented ischaemia on electrocardiogram, male sex, prior myocardial infarction, treatment with intra-aortic balloon pump counterpulsation, heart failure, and higher peak levels of creatine kinase-MB. CONCLUSIONS: The risk factors obtained from the medical history and during the hospitalisation improve the risk stratification during the post-discharge period after hospitalisation for ACS.