Changing Mortality from Ischaemic Heart Disease and Acute Myocardial Infarction

From 1969 to 1976 there was a significant reduction in mortality for various forms of ischaemic heart disease (IHD) in inpatients at the Royal Adelaide Hospital. The mortality rate for all forms of IHD fell from 22.9% to 8.8% in men, and from 26.7% to 14.5% in women; the rate for acute myocardial infarction fell from 28.5% to 16.1% in men, and from 38.4% to 25.1% in women; and the mortality rate for chronic IHD fell from 13.2% to 1.1% in men, and from 13.8% to 2.0% in women. A less marked decrease in mortality from acute myocardial infarction occurred in the general population. Numbers of hospital patients increased within each category of IHD. Admission of patients with less severe illness and changes in age and sex distribution may partially account for the observed reduction in hospital mortality.