Wan Yu, Hu Qiong, Shi Jing, Liu Limei, Zhang Xiangsong, Huang Jianjun, Wang Haijiu
Department of Hepatobiliary and Pancreatic Surgery, Qinghai University Affiliated Hospital, Xining, China.
Graduate School, Qinghai University, Xining, China.
Eur J Med Res. 2025 Mar 19;30(1):185. doi: 10.1186/s40001-025-02430-9.
Both blood urea nitrogen (BUN) and creatinine (Cr) are indicators of kidney function, and the BUN/Cr ratio has been identified as an independent prognostic marker for adverse outcomes in critically ill patients with various conditions. However, the relationship between the BUN/Cr ratio and long-term mortality in critically ill patients with acute pancreatitis (AP) remains unclear. Hence, the primary objective of this study was to determine the prognostic value of the BUN/Cr ratio in patients with AP.
We conducted a retrospective cohort study using data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. The primary exposure variable was the BUN/Cr ratio at intensive care unit (ICU) admission, and the primary outcome was 365-day all-cause mortality. Kaplan-Meier analyses and multivariate Cox proportional hazards models were used to assess this relationship, while restricted cubic spline (RCS) was used to explore potential non-linear associations. In addition, subgroup analyses were conducted to assess consistency between groups.
A total of 850 critically ill patients with AP were included, with a mean age of 59.61 years, 58.59% male, and an overall 365-day mortality rate of 20.94%. Patients in the highest BUN/Cr quartile had significantly higher mortality rates compared to those in lower quartiles. Multivariate Cox regression analysis demonstrated that, even after adjusting for potential confounders, an elevated BUN/Cr ratio remained an independent predictor of increased 28-day and 365-day mortality. RCS analysis confirmed a J-shaped relationship between the BUN/Cr ratio and 28-day and 365-day mortality, with a sharp increase in the risk of death above the 16.80 threshold. Subgroup analysis indicated that this association was consistent across various patient characteristics.
This study identified a non-linear relationship between the BUN/Cr ratio and 365-day mortality in critically ill patients with AP, suggesting that the BUN/Cr ratio may serve as an easily accessible, cost-effective, and accurate prognostic marker for this population.
血尿素氮（BUN）和肌酐（Cr）均为肾功能指标，且BUN/Cr比值已被确定为患有各种疾病的危重症患者不良结局的独立预后标志物。然而，急性胰腺炎（AP）危重症患者的BUN/Cr比值与长期死亡率之间的关系仍不清楚。因此，本研究的主要目的是确定BUN/Cr比值对AP患者的预后价值。
我们使用重症监护医学信息数据库IV（MIMIC-IV）的数据进行了一项回顾性队列研究。主要暴露变量是重症监护病房（ICU）入院时的BUN/Cr比值，主要结局是365天全因死亡率。采用Kaplan-Meier分析和多变量Cox比例风险模型评估这种关系，同时使用限制立方样条（RCS）来探索潜在的非线性关联。此外，进行亚组分析以评估组间的一致性。
共纳入850例AP危重症患者，平均年龄59.61岁，男性占58.59%，365天总死亡率为20.94%。BUN/Cr四分位数最高的患者与较低四分位数的患者相比，死亡率显著更高。多变量Cox回归分析表明，即使在调整潜在混杂因素后，升高的BUN/Cr比值仍然是28天和365天死亡率增加的独立预测因素。RCS分析证实了BUN/Cr比值与28天和365天死亡率之间呈J形关系，在阈值16.80以上死亡风险急剧增加。亚组分析表明，这种关联在各种患者特征中是一致的。
本研究确定了AP危重症患者的BUN/Cr比值与365天死亡率之间存在非线性关系，这表明BUN/Cr比值可能是该人群易于获取、具有成本效益且准确的预后标志物。
