Supplementary Material for: Serum Human epididymis protein 4 as a prognostic predictor of new onset heart failure among women after acute coronary syndrome: a single-center retrospective study

Introduction: Little is known about the prognostic factors among women with acute coronary syndrome (ACS), partly due to the small number of women included in heart failure (HF) clinical trials. Human epididymis protein 4 (HE4) has been proven to be a new biomarker for acute and chronic HF over the years. We hypothesize that HE4 could be a promising predictor. Methods: This retrospective study analyzed data from Zhejiang Provincial People’s Hospital. This study included 302 female patients with ACS between January 1, 2021, and December 1, 2021. The primary outcome was new-onset HF after ACS during the 12-month follow-up period. We used a logistic regression model to evaluate the association between serum HE4 levels and the incidence of HF. Serum HE4 levels were measured at baseline (within 24 hours after admission). Results: Of the 302 female patients, 70 (23.2 %) developed new-onset HF within 12 months. Serum HE4 levels in patients with adverse events were significantly higher than those in patients without events (8.9 (7.3-11.5) pmol/dL vs. 5.9 (5.0-6.8) pmol/dL, P < 0.001). The levels of HE4, troponin I peak, left ventricular ejection fraction (LVEF), and estimated glomerular filtration rate (eGFR) were validated as independent predictors, with HE4 being the best laboratory predictor (area under the curve, 0.863; 95 % confidence interval, 0.817-0.909). Serum HE4 concentrations of > 6.93 pmol/dL distinguished patients at risk of HF with 82.9 % sensitivity and 78.0 % specificity (maximum Youden index J, 0.609). Moreover, HE4 levels were associated with an increased risk of HF. Discussion/Conclusion: We found a strong relationship between HE4 and the occurrence of HF after ACS among women, which might help identify patients at high risk of HF for whom close or intense management should be mandatory.