ORIGINAL RESEARCH article

Front. Nutr.

Sec. Clinical Nutrition

Volume 12 - 2025 | doi: 10.3389/fnut.2025.1562091

Nonlinear relationship between fibrinogen-to-albumin ratio and mortality in critically ill patients with sepsis: a retrospective cohort study

Provisionally accepted
Daishan  JiangDaishan Jiang*Xiaoyu  YuanXiaoyu YuanYanbo  ShenYanbo ShenTingting  BianTingting Bian
  • Affiliated Hospital of Nantong University, Nantong, China

The final, formatted version of the article will be published soon.

Background: The fibrinogen-albumin ratio (FAR) is recognized as a prognostic biomarker in several diseases, but its role in sepsis remains controversial. To elucidate the relationship between FAR and mortality risk in a large cohort of patients with sepsis.Methods: In this retrospective cohort study, we analyzed clinical data from the Medical Information Mart for Intensive Care IV Database (version 2.2) to investigate the mortality of sepsis patients. We employed restricted cubic spline curves and Cox regression models to evaluate the effect of FAR on mortality and conducted subgroup analyses to verify the consistency of our primary findings. Results: In our analysis of 4,615 sepsis patients, we observed that mortality risk initially decreased with increasing FAR values, reaching a minimum at approximately 94.5*10-3, before rising again. Cox regression analysis revealed differing hazard ratios (HRs) for FAR quartiles relative to the second quartile (Q2). At 28 days, adjusted HRs were 1.23 (95% CI: 1.03–1.46) for Q1, 1.14 (.96–1.36) for Q3, and 1.11 (.93–1.33) for Q4. By 90 days, these HRs adjusted to 1.25 (1.07–1.46) for Q1, 1.21 (1.04–1.41) for Q3, and 1.21 (1.03–1.42) for Q4. This pattern persisted at 1-year mortality, with HRs of 1.16 (1.00–1.33) for Q1, 1.22 (1.06–1.39) for Q3, and 1.24 (1.07–1.43) for Q4. Conclusions: FAR exhibited a nonlinear, U-shaped association with mortality risk at 28 days, 90 days, and one year in patients with sepsis. These findings suggest that FAR may serve as a practical prognostic biomarker to support early risk stratification and clinical decision-making in sepsis care.

Keywords: Sepsis, fibrinogen-to-albumin ratio, Mortality, biomarkers, MIMIC database

Received: 16 Jan 2025; Accepted: 03 Jun 2025.

Copyright: © 2025 Jiang, Yuan, Shen and Bian. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Daishan Jiang, Affiliated Hospital of Nantong University, Nantong, China

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