Sex Differences in Long-Term Cause-Specific Mortality After Percutaneous Coronary Intervention: Temporal Trends and Mechanisms.

BACKGROUND

Women have higher rates of all-cause mortality after percutaneous coronary intervention. Whether this is because of greater age and comorbidity burden or a sex-specific factor remains unclear.

METHODS AND RESULTS

We retrospectively assessed cause-specific long-term mortality after index percutaneous coronary intervention over 3 time periods (1991-1997, 1998-2005, and 2006-2012). Cause of death was determined using telephone interviews, medical records, and death certificates. We performed competing risks analyses of cause-specific mortality. A total of 6847 women and 16 280 men survived index percutaneous coronary intervention hospitalization 1991 to 2012. Women were older (mean±SD: 69.4±12 versus 64.8±11.7 years; <0.001) with more comorbidities (mean±SD: Charlson index 2.1±2.1 versus 1.9±2.1; <0.001). Across the 3 time periods, both sexes exhibited a decline in cardiac deaths at 5 years (26% relative decrease in women, 17% in men, trend <0.001 for each). Although women had higher all-cause mortality compared with men in all eras, the excess mortality was because of noncardiac deaths. In the contemporary era, only a minority of deaths were cardiac (33.8% in women, 38.0% in men). After adjustment, there was no evidence for a sex-specific excess of risk for cardiac or noncardiac mortality. The commonest causes of death were chronic diseases and heart failure in women (5-year cumulative mortality, 5.4% and 3.9%) but cancer and myocardial infarction/sudden death in men (5.4% and 4.3%).

CONCLUSIONS

The higher mortality after percutaneous coronary intervention in women is because of death from noncardiac causes. This is accounted for by baseline age and comorbidities rather than an additional sex-specific factor. These findings have implications for sex-specific clinical care and trial design.