Age-Stratified Sex-Related Differences in the Incidence, Management, and Outcomes of Acute Myocardial Infarction

Objective: To assess the impact of female sex on the incidence, management, and outcomes of myocardial infarction (MI) in different age groups. Methods: Patients admitted with ST-elevation MI (STEMI) and non–ST-elevation MI (NSTEMI), between January 1, 2003, and December 31, 2015, were identified in the National Inpatient Sample. We compared STEMI and NSTEMI rates, management patterns, and in-hospital morbidity and mortality in men and women stratified into 4 age groups (<45, 45 to 64, 65 to 84, and ≥85 years of age). Results: A total of 6,720,639 weighted hospitalizations for MI (79.8% NSTEMI, and 20.2% STEMI) were included. The incidence rate of hospitalizations for MI was lower in women than men across all age groups. Women were less likely than men to undergo coronary angiography, revascularization, or to use circulatory-support devices. These differences were consistent across all age groups. Adjusted odds of death for women (vs men) varied by age: odds ratio (95% confidence interval) 1.08 (0.97 to 1.20), 1.05 (1.02 to 1.08), 0.92 (0.91 to 0.94), and 0.86 (0.85 to 0.88) for NSTEMI, and 1.15 (1.04 to 1.27), 1.22 (1.18 to 1.26), 1.09 (1.06 to 1.11), and 0.97 (0.94 to 0.99), for STEMI, in age groups (<45, 45 to 64, 65 to 84, and ≥85), respectively. The magnitude of differences in complications between men and women was higher in younger and middle-age patients. Conclusion: Compared with men, women have lower incidence of MI and less likelihood of undergoing invasive treatment regardless of age. However, post-MI outcomes are age specific. The negative impact of female sex on most outcomes was most pronounced in young and middle-aged women.