Worse outcomes in young women compared to men presenting with ST-elevation myocardial infarction: a 15-year statewide population-linkage cohort study

Abstract

Abstract Background Gender disparity in outcomes among patients presenting with acute ST-elevation myocardial infarction (STEMI) is well recognised. It is unclear whether the gap has improved with contemporary management and therapies over time. This study compared the 30-day mortality between women and men admitted with STEMI from 2003-2017. Purpose To examine whether the gender disparity in 30-day mortality following STEMI is consistent across patient age groups and whether it has changed over time with contemporary management. Methods We used the NSW Admission-Patient-Data-Collection (APDC) database which maintains the admission records of more than 97% of the state’s healthcare facilities to identify consecutive STEMI patients admitted from 1-Jan-2003 to 31-Dec-2017. Cause-specific mortality (classified as cardiac, non-cardiac) was identified from death certificates. Multivariable logistic regression analysis was performed to examine the impact of gender on mortality adjusted for comorbidities, admission year-groups, PCI during STEMI, and stratified by age groups of ≤60, 61-70 and >70yo. Results The study cohort comprised 65033 STEMI patients: 32% women (n=20825; median age 76.1yrs); 68% men (n=44208; median age 63.8yrs). The overall 30-day all-cause and cardiac mortality was 11.5% and 8.3% respectively, with women having worse outcomes compared to men (all-cause: 17.0% vs 8.9%; cardiac: 12.2% vs 6.5% respectively, both p<0.0001). Following adjustment, higher mortality among women persisted: adjusted odds ratio [aOR]=1.65 (95% confidence interval [CI]=1.40-1.94) and 1.55 (95%CI=1.28-1.87) for total and cardiac mortality respectively. The gender disparity in mortality did not change during the study period. There was an interaction between age and gender so that differences in gender specific mortality were greater in younger than in older patients: total mortality women vs men ≤60yrs aOR=1.65 (95%CI=1.40-1.94), >70yrs aOR=1.19 (95%CI=1.12-1.27), p(interaction)=0.0011; cardiac mortality women vs men ≤60yrs aOR=1.55 (95%CI=1.28-1.87), >70yrs aOR=1.17 (95%CI=1.09-1.25), p(interaction)=0.026. Unexpectedly, a similar age-gender interaction was observed for non-cardiac mortality: women vs men ≤60yrs aOR=1.88 (95%CI=1.41-2.51), >70yrs aOR=1.15 (95%CI=1.03-1.28), p(interaction)=0.0063. Conclusion Women admitted with STEMI have significantly higher 30-day mortality than their male counterparts, with no improvement in gender disparity during the study period. The gender-bias is most pronounced in the younger age-group across and is observed for both cardiac and non-cardiac mortality. Further efforts are needed to identify the drivers of worse outcomes following STEMI in younger women.