Abstract P275: Incidence and Case-Fatality Rates of Acute Myocardial Infarction in the United States: A Systematic Review

Abstract

Introduction: Beginning in the late 1960s, the death rates attributed to coronary heart disease (CHD) in the U.S. declined, including deaths due to acute myocardial infarction (AMI). The decline in AMI related mortality is likely related to both a decrease in the incidence rates of new events in addition to declines in case-fatality rates (CFRs). The purpose of this summary over view is to describe long-term trends in the incidence and short-term CFRs after AMI in the US based on data from population-based community surveillance studies and, secondarily, to examine possible demographic differences in any observed trends. Methods: Systematic review of published studies providing data on incidence and/or CFRs after AMI in the U.S. published in English between 1980 and 2009. Results: Twenty one out of 436 retrieved articles met our eligibility criteria. Our findings are based on the results of 9 community surveillance studies covering different geographic locations and time periods. Eight studies where done in predominantly White populations. Incidence rates: Studies that had no upper age limits failed to show significant declines in overall incidence rates of AMI over the periods under study. Studies that had an upper age limit reported declines (Minnesota Heart Survey (MHS) 25% decline) or no changes (Atherosclerosis Risk in the Community (ARIC)) in the incidence rates of AMI. Declines were primarily observed in younger White men. Case-fatality rates: All studies reported declining short-term (hospital) CFRs (50% decline since the late 1960s). Declines were greatest among younger individuals. Unadjusted CFRs were 1.5 fold higher in women and non-Whites compared to men and Whites, respectively. Conclusion: Our review demonstrated encouraging declines in short-term CFRs after AMI while incidence rates did not show similar trends. Aging of the population and changes in AMI definitions might have played a role in the observed trends in AMI incidence rates. Advances in pre-hospital care, management, and critical cardiac care likely contributed to the declines in CFRs observed.