IMPROVING LONG-TERM SURVIVAL OF PATIENTS WITH ACUTE MYOCARDIAL-INFARCTION FROM 1977-1988 IN A REGION OF DENMARK

The aim of this investigation was to study secular trends in long-term survival following myocardial infarction (MI). Five thousand one hund red and fifty-seven consecutive cases of MI in 3942 patients were reco rded in a well-defined region in the study period 1977-1988. The study period ended before thrombolytic therapy was introduced in the hospit al One and 5-year survival (+/- 95% confidence limits) was 61 +/- 2% a nd 42 +/- in 1977-1980. These figures changed to 61 +/- 2% and 44 +/- 2% in 1981-1984, and to 64 +/- 2 and 46 +/- 2% in 1985-1988. The impro vement with time was statistically significant (P < 0.001). In a Cox p roportional hazard model, time of infarction was an independent predic tor of survival. Patients were subdivided into a high risk group suffe ring from either congestive heart failure or cardiac arrest during hos pitalization, and a low risk group without these complications. Year o f infarction was without importance in the high risk group but highly significant in the low risk group.Long-term survival following MI grad ually improved prior to rite introduction of thrombolytic therapy. The improvement was confined to low risk patients without cardiac arrest or congestive heart failure.