UCLA

Background

Little is known whether time trends of in-hospital mortality and costs of care for acute myocardial infarction (AMI) differ by type of AMI (ST-elevation myocardial infarction [STEMI] vs. non-ST-elevation [NSTEMI]) and by the intervention received (percutaneous coronary intervention [PCI], coronary artery bypass grafting [CABG], or no intervention) in the United States.

Methods and results

We conducted a serial cross-sectional study of all hospitalizations for AMI aged 30 years or older using the Nationwide Inpatient Sample, 2001-2011 (1,456,154 discharges; a weighted estimate of 7,135,592 discharges). Hospitalizations were stratified by type of AMI and intervention, and the time trends of in-hospital mortality and hospital costs were examined for each combination of the AMI type and intervention, after adjusting for both patient- and hospital-level characteristics. Compared with 2001, adjusted in-hospital mortality improved significantly for NSTEMI patients in 2011, regardless of the intervention received (PCI odds ratio [OR] 0.68, 95% CI 0.56 to 0.83; CABG OR 0.57, 0.45 to 0.72; without intervention OR 0.61, 0.57 to 0.65). As for STEMI, a decline in adjusted in-hospital mortality was significant for those who underwent PCI (OR 0.83; 0.73 to 0.94); however, no significant improvement was observed for those who received CABG or without intervention. Hospital costs per hospitalization increased significantly for patients who underwent intervention, but not for those without intervention.

Conclusions

In the United States, the decrease in in-hospital mortality and the increase in costs differed by the AMI type and the intervention received. These non-uniform trends may be informative for designing effective health policies to reduce the health and economic burdens of AMI.