The Prognostic Significance of the DBIL/HDLC Ratio in Patients With Dilated Cardiomyopathy

Background: In cardiovascular pathology, both direct bilirubin (DBIL) and high-density lipoprotein cholesterol (HDLC) have been associated with adverse clinical outcomes. However, the prognostic significance of these biomarkers in the context of dilated cardiomyopathy (DCM) remains unclear. To address this gap, this study conducted a retrospective analysis to evaluate the prognostic value of the DBIL/HDLC ratio in patients diagnosed with DCM. Methods and Results: A total of 986 consecutive DCM patients were retrospectively enrolled from January 2010 to December 2019 and divided into two groups based on the DBIL/HDLC ratio cut-off value: ≤ 4.45 (n = 483) and > 4.45 (n = 503). Patients with lower DBIL/HDLC (≤ 4.45) experienced lower in-hospital mortality, long-term mortality, and major adverse clinical events (MACEs) (0.8%, 32.9%, and 12.2%, respectively) compared to those with higher DBIL/HDLC (> 4.45) (6.4%, 59.1%, and 16.7%, respectively). Multivariate analysis identified DBIL/HDLC as an independent risk factor for long-term mortality (odds ratio: 1.026; 95% confidence interval (CI): 1.005–1.048; p = 0.016) and all-cause mortality over a median follow-up of 67 ± 1.8 months (hazard ratio: 1.011; 95% CI: 1.005–1.018; p < 0.001). The receiver operating characteristic curve showed good discrimination for long-term mortality (area under the curve (AUC): 0.675; 95% CI: 0.692–0.708; p < 0.001). The Kaplan–Meier survival analysis demonstrated a better prognosis for patients with DBIL/HDLC ≤ 4.45 (log-rank χ² = 40.356, p < 0.001). Furthermore, the impact of additional variables on the results was investigated by a subgroup analysis. Conclusion: The DBIL/HDLC ratio could serve as a simple and cost-effective tool for evaluating prognosis in DCM.