血清铁水平与脓毒症相关性脑病患者90天全因死亡率的关系：一项回顾性队列研究

Association between serum iron levels and 90⁃day all⁃cause mortality in sepsis⁃associated encephalopathy patients: A retrospective cohort study

摘要

目的：脓毒症相关性脑病（SAE）是脓毒症常见且严重的并发症，与高死亡率相关。血清铁（SI）水平对SAE患者预后的影响仍未充分探索。本研究旨在调查重症监护病房（ICU）入院时SI水平与SAE患者90天全因死亡率之间的关系。方法：使用重症监护医学信息市场Ⅳ（MIMIC-Ⅳ）数据库进行回顾性队列研究。研究对象为诊断为SAE并入住ICU的成年患者。根据入院时SI水平的四分位数分为Q1~Q4组。使用Kaplan-Meier曲线比较SI四分位数组间的90天全因死亡率。采用多变量Cox比例风险回归模型和限制性立方样条（RCS），在调查潜在混杂因素后，分析SI水平与患者90天死亡率之间的关系。结果：研究纳入了650名SAE患者。中位年龄为72岁（四分位数间距：60~82岁），48.9%为男性。Kaplan-Meier曲线显示不同SI四分位数组间的90天全因死亡率存在显著差异（log-rank检验，P=0.023）。在包含所有协变量的完全调整模型（模型Ⅴ）的多变量Cox回归分析中，较高的SI水平仍与90天全因死亡率增加独立相关[Q1与Q4组相比，风险比（HR）=2.026，95%置信区间（CI）：1.222~3.359，P=0.003]，且该关联在逐步调整的各模型中保持一致。RCS分析显示SI水平与90天全因死亡率之间存在线性剂量-反应关系（非线性P=0.68）。结论：ICU入院时升高的SI水平与SAE患者90天全因死亡率增加独立相关，呈线性剂量-反应关系。研究表明SI水平可能作为SAE患者有价值的预后标志物。其结果有待前瞻性研究进一步验证并探索潜在机制。

Abstract

Objective: To investigate the association between serum iron (SI) levels at intensive care unit (ICU) admission and 90-day all-cause mortality in patients with sepsis-associated encephalopathy (SAE). Methods: A retrospective cohort study was conducted by using data from the medical information mart for intensive care Ⅳ (MIMIC-Ⅳ) database. Adult patients diagnosed with SAE and admitted to the ICU were included. The patients at ICU admission were categorized into Q1 to Q4 groups according to quartiles of SI levels. Kaplan-Meier curves were used to compare 90-day all-cause mortality across SI quartiles. Multivariable Cox proportional hazards models and restricted cubic spline (RCS) analyses were employed to assess the relationship between SI levels and 90-day mortality, adjusting for potential confounders. Results: A total of 650 SAE patients were included. The median age was 72 years (IQR 60-82), and 48.9% were male. Kaplan-Meier analysis showed significant differences in 90-day all-cause mortality across SI quartiles (log-rank test,P=0.023). In the fully adjusted model (Model Ⅴ) that included all covariates, higher SI levels remained independently associated with increased 90-day mortality (Q1 vs Q4, hazard ratio (HR)=2.026, 95% confidence interval: 1.222-3.359, P=0.003). This association was consistent across all five models with stepwise adjustment for confounders. RCS analysis indicated a linear relationship between SI levels and 90-day mortality (nonlinearityP=0.68). Conclusion: Elevated SI levels at ICU admission are independently associated with higher 90-day all-cause mortality among patients with SAE in a linear dose-response manner. These findings suggest that SI may serve as a valuable prognostic biomarker in SAE. Prospective studies are warranted to validate these results and elucidate underlying mechanisms.

关键词

脓毒症相关性脑病 / 血清铁 / 死亡率 / 回顾性队列研究 / MIMIC数据库

Key words

Sepsis-Associated Encephalopathy / Serum Iron / Mortality / Retrospective Cohort Study / MIMIC Database

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基金资助

深圳市基础研究计划(JCYJ20220530142411026)

中国高水平医院计划(HKUSZH202207002)

广东省卫生健康委员会医疗卫生科研项目(A2024193)

深圳市宝安区科技创新局医疗卫生科研项目(2022JD195)