Interleukin-6 as a novel biomarker for the diagnosis of acute decompensated heart failure: a retrospective study

Background Interleukin-6 (IL-6) is associated with the pathogenesis of heart failure (HF) and an increased HF risk in people without previous myocardial infarction. However, little is currently known about the correlation between IL-6 and acute decompensated heart failure (ADHF). Objective To determine whether IL-6 could serve as a diagnostic biomarker for ADHF in Chinese patients without acute myocardial infarction. Patients and methods A total of 122 patients were included in our study [58 ADHF, 64 chronic HF (CHF)]. Plasma IL-6 and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were measured. Logistic regression analyses and a receiver operating characteristic (ROC) curve were performed to determine the diagnostic value of IL-6. Results Plasma levels of IL-6 and NT-proBNP were higher in ADHF patients than CHF patients. IL-6 correlated positively with NT-proBNP, heart rate, and left ventricular end-diastolic dimension, and inversely with left ventricular ejection fraction. After adjustment, IL-6 remained independently associated with ADHF (OR = 1.461, 95% CI: 1.053–2.028, p = 0.023). The optimal cut-off value of IL-6 for ADHF diagnosis was 5.00 pg/mL, and the sensitivity, specificity, and Youden index were 81.0%, 87.5%, and 0.685, respectively. Conclusions IL-6 is independently associated with ADHF and shows promising diagnostic accuracy. The cut-off of 5.00 pg/mL provides a novel reference for Chinese ADHF patients without AMI, offering clinical evidence for research on inflammation-related biomarkers of cardiovascular diseases. Combined use with NT-proBNP may enhance diagnostic accuracy, but prospective validation is needed.