Background: Acute kidney injury (AKI) is a common and serious complication in critically ill patients, especially those with sepsis. Recent studies suggest that estimated pulse wave velocity (ePWV) is an independent prognostic factor for in-hospital mortality in AKI patients. The objective of this research is to examine the correlation between ePWV and 28-day mortality among patients with sepsis-related acute kidney injury (SA-AKI).

Methods: This retrospective cohort study utilized data from 16,514 patients with SA-AKI in the MIMIC-IV database. ePWV was categorized based on the ROC curve cutoff value, dividing patients into two groups: high (>10.535 m/s) and low (≤10.535 m/s). To compare survival outcomes between the groups, Kaplan-Meier survival analysis was conducted. Cox proportional hazards models were used to assess the association between ePWV and 28-day mortality, adjusting for potential confounders. Additionally, a restricted cubic spline (RCS) model was employed to explore a possible dose-response relationship. Stratified analyses were conducted to examine the effect of ePWV on 28-day mortality across different subgroups.

Results: Survival analysis revealed that individuals with high ePWV experienced poorer 28-day survival outcomes compared to those with low ePWV. After adjusting for confounding factors, ePWV continued to be a predictive factor for 28-day mortality in patients with SA-AKI (p < 0.001). RCS model demonstrated a nonlinear association between ePWV and 28-day mortality (p for nonlinearity = 0.035).

Conclusion: ePWV serves as an independent predictor of 28-day mortality in patients with SA-AKI. This metric offers prognostic insights to help clinicians identify high-risk patients early, enabling timely interventions and better clinical outcomes.

Keywords: 28-day mortality; Acute kidney injury; MIMIC-IV database; estimated pulse wave velocity; sepsis.

背景： 急性肾损伤（AKI）是重症患者常见的严重并发症，尤其是患有败血症的患者。最近的研究表明，估计脉搏波速度（ePWV）是住院死亡率在 AKI 患者中的独立预后因素。本研究旨在探讨 ePWV 与由败血症引起的急性肾损伤（SA-AKI）患者的 28 天死亡率之间的相关性。

方法： 这项回顾性队列研究使用了 MIMIC-IV 数据库中 16,514 名 SA-AKI 患者的数据。ePWV 根据 ROC 曲线截止值进行分类，将患者分为两组：高（>10.535 m/s）和低（≤10.535 m/s）。为了比较各组的生存结果，进行了 Kaplan-Meier 生存分析。使用 Cox 比例风险模型来评估 ePWV 和 28 天死亡率之间的关联，并调整潜在混杂因素的影响。此外，还使用了限制性立方样条（RCS）模型来探索可能的剂量反应关系。分层分析用于检查 ePWV 对不同亚组中 28 天死亡率的影响。

结果： 生存分析显示，高 ePWV 的个体在 28 天内的生存结局比低 ePWV 的个体差。调整混杂因素后，ePWV 仍是对 SA-AKI 患者 28 天死亡率的预测因子（p

结论： ePWV 是 SA-AKI 患者 28 天死亡率的独立预测因子。该指标提供了预后信息，有助于临床医生早期识别高风险患者，从而及时干预并获得更好的临床结果。

关键词： 28 天死亡率；急性肾损伤；MIMIC-IV 数据库；估计脉搏波速度；败血症。