Plasma-free 4-hydroxynonenal serves as an independent predictive biomarker for short-term prognosis in patients with heart failure complicated by renal dysfunction

Background: Patients with heart failure (HF) complicated by renal dysfunction (RD) carry an exceedingly poor prognosis, and there is a lack of precise predictive biomarkers. 4-Hydroxynonenal (4-HNE) can exacerbate cardiorenal injury, but its association with HF complicated by RD remains unclear. We aimed to investigate the predictive value of plasma-free 4-HNE for adverse clinical outcomes in patients with HF complicated by RD. Methods: This prospective study enrolled 114 patients with HF (New York Heart Association class III–IV) and RD (estimated Glomerular Filtration Rate [eGFR] ≤ 60 mL/min/1.73 m 2 ). Plasma-free 4-HNE levels were measured upon hospital admission. The primary outcome was in-hospital mortality. Secondary outcomes included major adverse cardiovascular events (MACE) and a reduction rate in N-terminal pro-B-type natriuretic peptide (NT-proBNP) ≥30%. Predictive value was assessed using receiver operating characteristic curves and logistic regression analyses. Results: The area under the curves of 4-HNE for predicting in-hospital mortality, MACE, and NT-proBNP reduction ≥30% were 0.700, 0.772, and 0.639, respectively. Multivariate regression analysis showed that 4-HNE was an independent predictive factor for in-hospital mortality (odds ratios [OR]: 3.74 [1.73–9.37]), MACE (OR: 7.21 [2.28–18.38]), and failure to achieve NT-proBNP reduction ≥30% (OR: 0.40) (all P < 0.05). Conclusion: Plasma-free 4-HNE can predict in-hospital mortality, MACE, and NT-proBNP reduction in patients with HF complicated by RD. This finding indicates that 4-HNE serves as an independent predictive factor for adverse short-term outcomes, thereby facilitating the clinical identification of high-risk patient populations.