Lower Post Myocardial Infarction Mortality among Women Treated at Veterans Affairs Hospitals Compared to Men

Abstract

Background: There is conflicting evidence about whether mortality after myocardial infarction is higher among women than among men. This study aimed to compare sex differences in post myocardial infarction mortality in the Veterans Affairs system, a setting where the predominant subjects are men. Materials and methods: The Veterans Affairs Corporate Data Warehouse inpatient and laboratory chemistry databases were used to identify patients diagnosed with acute myocardial infarction from inpatient records from January 1st, 2005 to April 25th, 2015. Mortality data was obtained through the Veterans Affairs death registry. Results: A total of 130,241 patients were identified; 127,711 men (98%) and 2,530 women (2%). Men typically had more comorbidities including congestive heart failure (54% vs. 46%, P value < 0.001), diabetes mellitus (54% vs. 48%, P value < 0.001), and chronic kidney disease (39% vs. 28%, P value < 0.001). The peak troponin-I was significantly higher among men (16.0 vs. 10.7 ng/mL, P value = 0.03). The mean follow-up time was 1490.67 ± 8 days. After adjusting for differences in demographics and comorbidities, women had a significantly lower risk of mortality (hazard ration [HR]: 0.747, P value < 0.0001) as compared to men. Conclusions: In a health care system where the predominant subjects are men, women had better short- and long-term survival than men after an acute myocardial infarction. Further investigation is warranted to determine the reasons behind the improved outcomes in women post myocardial infarction in the veteran population.