[Mortality after myocardial infarction has decreased in nearly all Swedish counties during the 1990's. Greatest improvement seen in those counties with the worst initial results].

In an international perspective, Sweden has a very low case fatality after acute myocardial infarction (AMI). The aim of this study was to present trends and regional differences in case fatality within 28 days of the first AMI for males and females in Sweden after adjusting for co-morbidity. Adjustments in order to remove random effects on the rank order of county councils were made. The study was based on national data on more than 500,000 cases of AMI. Between 1987 and 1999, case fatality after AMI decreased from 47% to 37% among men and from 44% to 34% among women. The case fatality in the individual counties varied from 29% to 37% for men and from 31% to 40% for women. Further analysis is needed in order to explain these variations.