Socio-economic position and time trends in invasive management and case fatality after acute myocardial infarction in Denmark

Abstract

Background: Lower case fatality and increased use of evidence-based invasive management incl. coronary angiography (CAG) have been reported for patients admitted with acute myocardial infarction (AMI) in the last 25 years. This article seeks to investigate whether these advances have benefitted patients in all socio-economic groups and how this has impacted on inequality in case fatality. Methods: Forty three thousand eight hundred and forty three patients admitted with AMI in the period from 2001 to 2009 were included. Socio-economic position was measured using individual information on education. Age-standardized cumulative incidence of CAG within 1, 3 and 30 days along with age-standardized case fatality within 30 and 365 days were estimated. Cox regression models were used to model the relative inequality over time. Results: Use of CAG within 1, 3 and 30 days increased for all educational groups over time and the inequality in CAG within 1 and 3 days seen in the beginning of the time frame was eliminated. Case fatality decreased in all educational groups and the relative inequality in 30 days case fatality decreased for women but not 365 days case fatality. No change was seen for inequality in case fatality for men. Conclusion: Increased use of CAG within the evidence based time frame was observed along with a decrease in inequality. However, a reduction in inequality was only observed for short term case fatality, and only for women. These results suggest that inequality in case fatality is not primarily driven by inequality in invasive management of AMI.