Clinical Outcomes in Younger Women Hospitalized With an Acute Myocardial Infarction: A Contemporary Population-Level Analysis

Abstract

Background: For younger women with acute myocardial infarction (AMI), little is known regarding their contemporary care pathways and clinical outcomes.

Methods: We studied AMI patients aged 18-55 years, hospitalized from April 1, 2009, to March 31, 2019, in Ontario, Canada. We compared trends in comorbidities, angiographic findings, and revascularisation rates in men and women. The primary outcome was 1-year all-cause mortality or readmission for unstable angina, AMI, heart failure, or stroke. Inverse probability of treatment weighting was used to account for differences in baseline clinical characteristics between men and women.

Results: Among the 38,071 AMI patients included, 8,077 (21.2%) were women. Over the study period, women had increasing rates of diabetes (24.8% to 34.9%; P_trend < 0.001), and declining rates of smoking (53.2% to 41.7%; P_trend < 0.005). Although most patients received coronary angiography (96%), coronary revascularisation was less frequent among women than men (percutaneous coronary intervention: 61.9% vs 78.8% [P < 0.001]; surgery: 4.1% vs 6.0% [P < 0.001]). Women had more normal coronary anatomy (5.8% vs 1.7%; P < 0.001) and nonobstructive disease (22.8% vs 9.3%; P < 0.001) than men. Compared with men, the primary composite end point was significantly increased among women (10.0% vs 7.9%, adjusted HR 1.11; P = 0.02) and related to increased readmission rates for cardiovascular events. All-cause readmission was significantly increased among women (25.8% vs 21.1%, adjusted HR 1.34; P < 0.0001).

Conclusions: Coronary angiography is performed almost universally in younger women with AMI; however, coronary revascularisation is less frequent, perhaps reflecting less obstructive disease. Although mortality rates after AMI were similar between sexes, cardiovascular readmission rates and all-cause readmissions were significantly increased among women.