Women with acute myocardial infarction (AMI) experience more adverse outcomes and are more likely to end up back in the hospital compared to men in the year following discharge, suggests a new study. Led by Mitsuaki Sawano, MD, PhD, from the Yale School of Medicine in New Haven, Connecticut, the research team found that these women have persistently worse outcomes compared with men immediately and 1 year after discharge. Further study results revealed that coronary-related hospitalizations were the most common cause of hospitalizations, but noncardiac hospitalizations show the greatest sex disparity among young patients after AMI. “This all begins with public awareness towards preventing heart attacks and screening programs to detect traditional risk factors before a patient has a heart attack. Many people think heart attacks only occur in middle-aged or older men, which is not true,” said Sawano in a news release announcing the study results. ““People need to be aware that heart attacks occur in young women as well and they can present with atypical symptoms. “After experiencing a heart attack, young women will be more likely to need a 360-level approach.” The study was published Monday online and in the May 9 issue of the Journal of the American College of Cardiology. Data from the VIRGO observational study Researchers used data from the Prospective, Multicenter Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients (VIRGO) observational study. The study included young women and men with AMI aged 18 to 55 years across 103 hospitals in the U.S. from August 2008 to January 2012 using a strict 2:1 enrollment ratio of women to men. For the present study, 2,985 U.S. patients (n=2,009 women, n=976 men) hospitalized for AMI were included. After excluding in-hospital deaths (n=6), this resulted in a cohort of 2,979 participants. The primary outcomes of the study were all-cause and cause-specific acute events requiring hospitalization, defined as any hospital or observation stay >24 hours within 1 year of discharge. Results revealed that among the patients, at least one hospitalization occurred among 905 patients (30.4%) in the year after discharge. The leading causes of hospitalization were coronary-related (incidence rate [IR]: 171.8; 95% confidence interval [CI]: 153.6-192.2) among women compared to an IR of 117.8 (95% CI: 97.3-142.6) among men. This was followed by noncardiac hospitalization (IR: 145.8; 95% CI: 129.2-164.5) among women compared to men (IR: 69.6; 95% CI: 54.5-88.9). Sex disparity for hospitalizations Further findings revealed a sex difference was present for coronary-related hospitalizations (subdistribution hazard ratio [SHR]: 1.33; 95% CI: 1.04-1.70; P=0.02) and noncardiac hospitalizations (SHR: 1.51; 95% CI: 1.13-2.07; P=0.01). “We think young women who present with heart attacks tend to have a greater burden of cardiovascular risk factors compared with men. In general, young, premenopausal women are protected by their own estrogen hormone to have lower incidence of heart attacks.,” Sawano said in the news release. “Thus, to overcome this physiological protection, we think a higher accumulation of risk factors, such as obesity, high blood pressure, high cholesterol, cigarette smoking, etc., is needed to cause a ‘breakthrough’ effect.” Sawano suggested that for women, this greater number of risk factors is likely to cause difficulty controlling them after discharge. Worse control of risk factors is associated with worse outcomes, including recurrence of heart attacks, chest pain due to the heart, as well as other atherosclerotic diseases like stroke, he commented. MI-CAD and MINOCA populations On the sex disparity for non-cardiac hospitalizations compared to all other hospitalizations, Sawano said: “We think that the accumulation of risk factors seen in the myocardial infarction with obstructive coronary artery disease (MI-CAD) population is associated with the high incidence of hospitalization one year after heart attack. We must emphasize, however, that does not mean that patients with myocardial infarction with non-obstructive coronary arteries (MINOCA) are ‘low risk.’ We know from recent studies that MINOCA is not a benign disease compared with similarly aged women and these cases warrant further evaluation to understand the underlying mechanism and treatment of certain conditions.” In an accompanying editorial, Martha Gulati, MD, of the Cedars-Sinai Heart Institute in Los Angeles, and colleagues, wrote that the study highlights the “increased rate of cardiovascular and non-cardiovascular rehospitalization in women as compared to men, with a clear association between psychosocial and demographic factors.” “Yet the root cause of sex differences in psychosocial factors and rates of comorbid conditions remains elusive, the editorialists continued. “Why are more women than men identified as low-income in this cohort? Why does this cohort demonstrate a nearly two-fold greater prevalence of depression in women as compared to men? As a cardiovascular community, by continuing to ask why perhaps we can arrive at ‘what next.,’” Study limitations The expert commenters identified details of non-cardiac hospitalizations that were not collected as a study limitation. Other limitations include the results that may not be generalizable to population groups underrepresented in the study cohort. Sources: Sawano M, Lu Y, Caraballo C, et al. Sex Difference in Outcomes of Acute Myocardial Infarction in Young Patients. J Am Coll Cardiol. 2023;81:1797–1806 Gulati M, Holtzman JN, Kaur G. Increased Rehospitalization in Young Women With Acute Myocardial Infarction at 1 Year: Adding Insult to Infarct. J Am Coll Cardiol. 2023;81:1807–1809 Image Credit: Pixel-Shot – stock.adobe.com