Associations of Inflammatory Biomarkers with Disease Severity in Elderly Patients with Sepsis-Associated ARDS: A Cross-Sectional Study.

Background: Sepsis-associated acute respiratory distress syndrome (ARDS) is associated with high mortality, particularly in elderly patients. Reliable biomarkers for early severity stratification remain limited. Objective: To evaluate the associations of four inflammatory biomarkers-endothelial cell-specific molecule-1 (ESM-1), soluble urokinase plasminogen activator receptor (suPAR), procalcitonin (PCT), and heparin-binding protein (HBP)-with disease severity in elderly patients with sepsis-associated ARDS. Methods: This cross-sectional study included 168 elderly patients (≥60 years) with sepsis-associated ARDS. Serum levels of ESM-1, suPAR, PCT, and HBP were measured at enrollment. Disease severity was assessed using the APACHE II, SOFA, and MLIS scores, and the PaO Results: All four biomarkers increased stepwise across the mild, moderate, and severe ARDS groups (all P < 0.001). ESM-1 showed the strongest correlation with ARDS severity ( Conclusion: ESM-1, PCT, and HBP are independently associated with disease severity in elderly patients with sepsis-associated ARDS. ESM-1 demonstrated discriminative ability comparable to conventional severity scores and may serve as an adjunctive marker for severity assessment at enrollment, pending prospective validation. Limitations include the single-center, cross-sectional design and the lack of external validation.