Mortality after acute myocardial infarction is lower in rnetropolitan regions than in non-metropolitan regions

Study objectives-To compare inhospital mortality for acute myocardial infar ction (AMI) between metropolitan and nonmetropolitan hospitals after adjust ment for patients' severity; to examine the role of the use of effective ca rdiac medications in the possible mortality difference between these types of hospital. Design-Retrospective cohort study. Setting-47 acute public hospitals in metropolitan and non-metropolitan area s of New South Wales, Australia, taking part in the Acute Cardiac Care Proj ect based on medical record review. Patients-1665 patients with principal discharge diagnosis of AMI from Febru ary to June 1996. Main results-There was no difference in crude mortality rate (assessed as s even day mortality) between metropolitan and non-metropolitan hospitals (11 .0% compared with 10.7% respectively, p=0.893). After adjustment for severi ty in a logistic regression model, the odds of death in non-metropolitan ho spitals was significantly higher than in metropolitan hospitals (odds ratio = 1.90; 95% CI 1.21, 3.23). The addition of the use of effective cardiac m edications to the model resulted in the difference between hospital type be coming non-significant (odds ratio=1.09; 95% CI 0.57, 2.07). Conclusions-Inhospital mortality in non-metropolitan hospitals was higher t han that in metropolitan hospitals, after adjustment for patients' severity . This might partly be explained by the difference in use of effective card iac medications between hospital type.