Introduction: Our purpose was to evaluate treatment and mortality in an unselected consecutive patient population hospitalised with definite acute coronary syndrome (ACS) in 2000 and 2003., Materials and Methods: From 1 September 2000 to 15 January 2001 and from 1 September 2003 to 15 January 2004, all patients hospitalised in the Department of Cardiology, Odense University Hospital, Denmark, with ACS were consecutively registered., Results: 396 patients with ACS were included, 200 in 2000 and 196 in 2003. Their mean age increased from 68 +/- 12.5 years in 2000 to 71 +/- 13.4 years in 2003, p = 0.03. The number of patients older than 75 years of age increased from 35% in 2000 to 44% in 2003, p < 0.001. The one-year mortality rate was 24% in 2000 and 22% in 2003. Cox regression analysis demonstrated that the risk of death was highest in older patients (RR 1.06, 95% CI 1.03-1.09, p < 0.001) adjusted for gender, type of myocardial infarction (MI) and previous MI. The mortality rate for patients < or = 75 years decreased from 2000 to 2003 during hospitalisation (5.3% vs. 4.6%), after 30 days (9.7% vs. 7.7%) and after 1 year (18.5% vs. 9.9%). From 2000 to 2003, a rise in invasive treatment strategy was observed, together with an increased use of statins and clopidogrel., Conclusion: Age is an independent predictor of mortality after ACS, and the age of patients hospitalised with ACS has increased. The one-year mortality rate is close to one fourth. For younger patients, the mortality rate has decreased. Compared to randomised clinical trials, a considerable discrepancy in mortality was observed, predominantly due to the restricted patient selection in such studies and the concomitant lack of representation of daily-life patients.