Differences in inhospital mortality between men and women with acute myocardial infarction undergoing percutaneous coronary intervention in Japan: Tokai Acute Myocardial Infarction Study (TAMIS)

Background It is a matter of concern that women have higher inhospital mortality rates than men with percutaneous coronary intervention (PCI); however, it is not yet clear whether significant sex differences exist. This study aimed to determine if there are sex differences in the characteristics and inhospital mortality among patients with acute myocardial infarction (AMI) undergoing PCI in Japan. Methods We used data from 13 acute care hospitals in the Tokai region (central Japan) included in the sample from the TAMIS, a retrospective study of all patients admitted to these hospitals from 1995 to 1997 with a diagnosis of AMI. We abstracted the baseline and procedural characteristics from detailed chart reviews which included not only physician notes but also nursing notes, and a questionnaire included baseline characteristics, procedural course, and inhospital mortality. Multivariate analysis was performed, controlling for age and other variables which were found to be significantly different between men and women by χ2 test or Mann-Whitney U test. Results In TAMIS, we had a total of 2020 subjects. A total of 303 women and 1033 men undergoing PCI were included in the present study. There were sex differences in age, comorbid conditions, smoking status, activities of daily living, and heart failure on presentation. In univariate analysis, women had a higher inhospital mortality rate than men; however, this sex difference disappeared after multivariable adjustment. Conclusions Our study demonstrates that women with AMI who undergo PCI do not have a significantly higher inhospital mortality rate than men in Japan; additional larger-scale studies are needed to confirm these results.