Present treatment of acute myocardial infarction in patients over 75 years--data from the Berlin Myocardial Infarction Registry (BHIR)

Abstract

Aims: Guidelines issued by European and German cardiology societies clearly define procedures for treatment of acute myocardial infarction (AMI). These guidelines, however, are based on clinical studies in which older patients are underrepresented. Older patients, on the other hand, represent a large and growing portion of the infarction population. It was our goal in the present paper to analyse the present treatment of AMI patients over 75 years of age in the city of Berlin, Germany, with data gained from the Berlin Myocardial Infarction Registry (BHIR).

Methods: We prospectively collected data from 5079 patients (3311 men and 1768 women, mean age 65.6) with acute myocardial infarction who were treated in 25 hospitals in Berlin during the period 1999-2003. 1319 patients (25.9%) were older than 75 (mean age 82.5 years).

Results: Overall hospital mortality rate was 11.6%. In patients over 75, this rate was 23.9%; among the younger infarction population, it was 7.3%. In contrast to the younger AMI patients, the majority of those over 75 were female (62.5 vs 25.1% for the younger) and demonstrated a significantly higher frequency of all prognostically meaningful comorbidities (heart failure 14.4% vs. 3.5%; renal failure 11.5 vs 3.9%; diabetes 37.3 vs 24.3%). Clinical signs of severe infarction, moreover, were more common among the aged patients (pulmonary congestion 45.4 vs 19.7%; left bundle branch block 12.7 vs 3.6%). Pre-hospital time was prolonged (2.8 vs 2 h) and guideline-recommended therapy was applied significantly less frequently to AMI patients over 75 (reperfusion therapy 39.8 vs 71.7%, beta-blockers 62.8 vs 78.3%, statins 26.5 vs 45.5%). Multivariate analysis revealed the following factors to be independent predictors of hospital mortality in patients over 75: age (OR 1.05 per year), acute heart failure (OR 2.39), pre-hospital resuscitation (OR 10.6), cardiogenic shock (OR 2.73), pre-hospital delay >12 h (OR 1.68), and ST elevation in the first ECG (OR 2.09). Independent predictors of a favourable hospital course were as follows: admission to a hospital >600 beds (OR 0.64), reperfusion therapy (OR 0.63), early betablocker treatment (OR 0.46), and early application of ACE inhibitors (OR 0.48).

Conclusion: Infarction patients over 75 have a very high hospital complication and mortality rate. They are typically treated with delay, and with less adherence to relevant guidelines than are younger patients. Reperfusion therapy, early administration of beta-blockers and ACE inhibitors, as well as admission to large medical centres are all factors that contribute to a favourable prognosis of high-aged AMI patients.