摘要BACKGROUND Acute decompensated heart failure(ADHF)is one of the leading causes of mortality,highlighting the import-ance of early identification of high-risk patients.The fibrosis-5(FIB-5)index,traditionally used to evaluate hepatic fibrosis,may ho-ld prognostic value in ADHF patients by reflecting systemic congestion,inflammation,and organ dysfunction.The hypothesis of th-is study is that the FIB-5 index is an independent predictor of 1-month mortality in patients with ADHF.METHODS This retrospective study included 155 patients diagnosed with ADHF between 2020 and 2024.Patients were divid-ed into two groups based on their left ventricular ejection fraction(LVEF ≤ 40％ or LVEF＞50％).Survival was monitored for one mo-nth,and clinical,biochemical,and echocardiographic parameters were compared between survivors and death.Logistic regress-ion and receiver operating characteristic curve analyses were performed to assess the prognostic value of the FIB-5 index.RESULTS During the 1-month follow-up,66 patients(42.6％)died.The mean FIB-5 index was significantly lower in non-surviv-ors(-10.46±6.93)compared to survivors(-8.10±6.67)(P=0.03).Multivariate regression analysis identified the FIB-5 index as an independent predictor of 1-month mortality(OR=1.089,95％ CI:1.022-1.160,P=0.009).The receiver operating characteristic cur-ve analysis demonstrated an area under the curve of 0.609(95％ CI:0.51-0.699)with sensitivity of 59.6％ and specificity of 63.4％.Ka-plan-Meier survival analysis revealed significantly higher mortality rates among patients with lower FIB-5 values(log-rank:7.887,P=0.005).CONCLUSIONS The FIB-5 index is an independent predictor of 1-month mortality in ADHF patients.Its low cost,non-invasive nature,and ability to reflect systemic inflammation and congestion make it a promising tool for risk stratification.Prospective stu-dies are needed to validate its utility in clinical practice and evaluate its role in guiding therapeutic decisions.