Jin Jun, Yu Lei, Cheung Kin, Deng Zihao, Zhou Qingshan, Liu Yong
Department of Intensive Care Unit, The University of Hong Kong-Shenzhen Hospital, Shenzhen, 518053, China.
School of Nursing, Hong Kong Polytechnic University, Hong Kong SAR, China.
Sci Rep. 2025 Aug 4;15(1):28331. doi: 10.1038/s41598-025-13341-4.
Recent studies have shown a significant association between iron and the development and prognosis of sepsis, but the relationship between iron levels and mortality in sepsis patients remains unclear, with previous studies examining this relationship under a linear assumption. This retrospective observational study aimed to assess the possible non-linear relationship between serum iron (SI) levels and 28-day all-cause mortality (28-DACM) in individuals with sepsis. We used multiple imputation for data with less than 30% missing values and developed Cox models to calculate the hazard ratio (HR) with a 95% confidence interval (CI) for the main outcome (28-DACM). To accurately assess the relationship between SI levels and the HR for 28-DACM, we utilized a restricted cubic spline (RCS) regression model with five knots. We also conducted subgroup analyses to evaluate the robustness of the primary results. The study found that SI levels upon ICU admission are an independent predictor of 28-DACM in sepsis patients, showing a J-shaped correlation with mortality. Patients with extremely high and low SI levels had higher mortality compared to those within the normal range. However, this study has limitations inherent to its retrospective observational design, such as potential bias and unmeasured confounding factors. Future studies should address these limitations through prospective designs.
最近的研究表明，铁与脓毒症的发生发展及预后之间存在显著关联，但铁水平与脓毒症患者死亡率之间的关系仍不明确，以往的研究是在线性假设下考察这种关系的。这项回顾性观察性研究旨在评估脓毒症患者血清铁（SI）水平与28天全因死亡率（28-DACM）之间可能存在的非线性关系。对于缺失值少于30%的数据，我们采用多重填补法，并建立Cox模型来计算主要结局（28-DACM）的风险比（HR）及其95%置信区间（CI）。为了准确评估SI水平与28-DACM的HR之间的关系，我们使用了带有5个节点的受限立方样条（RCS）回归模型。我们还进行了亚组分析以评估主要结果的稳健性。研究发现，脓毒症患者入住重症监护病房时的SI水平是28-DACM的独立预测因素，与死亡率呈J形相关性。与正常范围内的患者相比，SI水平极高和极低的患者死亡率更高。然而，本研究存在回顾性观察设计固有的局限性，如潜在偏倚和未测量的混杂因素。未来的研究应通过前瞻性设计来解决这些局限性。
