Impact of sex and its interaction with age on the management of and outcome for patients with acute myocardial infarction in 4 Japanese hospitals.

Background: Several studies from the United States and from European countries have detected sex and age differences in clinical characteristics, management, and outcomes of acute myocardial infarction. The aim of this study was to determine how sex and age influence the management of and outcome for patients with acute myocardial infarction in Japan.

Methods: A retrospective cohort study was performed by means of patient chart review at 4 teaching hospitals in Japan. There was a total of 482 patients (136 females [28%], 346 males [72%]) admitted consecutively with a diagnosis of acute myocardial infarction between July, 1995 and June, 1996.

Results: Female patients were older and had more comorbid diseases than male patients. Female patients also tended to have more cardiac complications during hospitalization and a greater 30-day mortality (10% vs 4%, P <.05). After adjustment for baseline characteristics and age/sex interaction, it was found that female patients were less likely to undergo thrombolytic therapy, cardiac catheterization, or revascularization, and they had a greater 30-day mortality. These sex differences in cardiac catheterization and revascularization were more pronounced for older patients. On the other hand, the sex differences in 30-day mortality were greater for younger patients.

Conclusions: Our data suggest that cardiac catheterization, revascularization and 30-day mortality may have been related to patient sex and age, but further study is needed.