Medical care and case fatality from myocardial infarction and coronary death in Newcastle and Perth.

Coronary mortality rates are significantly higher in Newcastle than Perth. In this paper we examine the extent to which this might be due to differences in medical treatment and case fatality. Population-based disease registers were used to identify all cases of non-fatal definite myocardial infarction (MI) and coronary death in people aged 25-64 years in the study populations between July 1988 and June 1990. Case fatality (at 28 days from onset of symptoms) was not significantly different between the centres. Thrombolytic therapy was used for one third of all hospitalised events in both centres. Other drugs of proven benefit were, however, used more often in Perth than in Newcastle. For example, during hospitalisation 74% of patients in Perth received beta-blockers compared with 41% in Newcastle (difference = 33%, 95% confidence interval (CI): 28%, 37%) and 85% of patients in Perth compared with 72% in Newcastle received aspirin (difference = 13%, 95% CI: 9%, 17%). Median lengths of stay in a coronary care unit (CCU) and total hospital stay were one day shorter in Perth. As case fatality was similar, the differences in mortality rates can be attributed mainly to differences in attack rates. Greater use of cardio-active drugs in Perth apparently did not result in improved short-term outcome although potential long-term benefits cannot be judged yet.