预后营养指数对腹膜透析患者心血管疾病死亡的影响：一项多中心回顾性队列研究

doi:10.12114/j.issn.1007-9572.2024.0340

中国全科医学 ›› 2025, Vol. 28 ›› Issue (05): 568-574.DOI: 10.12114/j.issn.1007-9572.2024.0340

预后营养指数对腹膜透析患者心血管疾病死亡的影响：一项多中心回顾性队列研究

朱露¹^,², 艾军¹, 廖生武³, 黄淑婷¹^,², 龚妮容¹, 孔耀中⁴, 刘德慧⁵, 窦献蕊⁶, 张广清⁷^,^*()

1．510515　广东省广州市，南方医科大学南方医院肾内科
2．510515　广东省广州市，南方医科大学护理学院
3．510515　广东省广州市，南方医科大学南方医院医技片区党总支
4．528000　广东省佛山市第一人民医院肾内科
5．341000　江西省赣州市人民医院肾内科
6．528300　广东省佛山市，南方医科大学顺德医院（顺德区第一人民医院）肾内科
7．510515　广东省广州市，南方医科大学南方医院院办公室

收稿日期:2024-05-16 修回日期:2024-09-28 出版日期:2025-02-15 发布日期:2024-11-25
通讯作者: 张广清
作者贡献：
朱露提出主要研究目标，负责研究的构思与设计，研究的实施，图、表的绘制与展示，统计学处理，撰写论文；艾军、廖生武进行论文的修订；黄淑婷、龚妮容、孔耀中、刘德慧、窦献蕊进行数据的收集、整理与清洗；艾军、张广清负责文章的质量控制与审查，对文章整体负责，监督管理。
基金资助:
国家自然科学基金资助项目(82370744); 广州市科技计划项目(202103000037)

Association of Prognostic Nutritional Index with Cardiovascular Mortality in Patients with Peritoneal Dialysis: a Multicenter Retrospective Cohort Study

ZHU Lu¹^,², AI Jun¹, LIAO Shengwu³, HUANG Shuting¹^,², GONG Nirong¹, KONG Yaozhong⁴, LIU Dehui⁵, DOU Xianrui⁶, ZHANG Guangqing⁷^,^*()

1. Department of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
2. School of Nursing, Southern Medical University, Guangzhou 510515, China
3. General Party Branch of Medical and Technical Area, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China
4. Department of Nephrology, the First People's Hospital of Foshan, Foshan 528000, China
5. Department of Nephrology, Ganzhou People's Hospital, Ganzhou 341000, China
6. Department of Nephrology, Shunde Hospital of Southern Medical University (First People's Hospital of Shunde District) , Foshan 528300, China
7. Hospital Office, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China

Received:2024-05-16 Revised:2024-09-28 Published:2025-02-15 Online:2024-11-25
Contact: ZHANG Guangqing

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摘要/Abstract

摘要： 背景心血管疾病（CVD）是腹膜透析（PD）患者死亡的主要原因，而营养不良是PD患者发生CVD及死亡的重要危险因素之一。预后营养指数（PNI）作为一种综合评估患者免疫、炎症和营养状态的指标，因其具有便利性与可靠性等优点，在肿瘤等多种疾病的预后评估中得到了广泛应用。然而，不同时间点的营养状态与PD患者预后之间的关系仍有待进一步探究。目的探讨PD患者首年PNI与CVD死亡之间的关系。方法本研究为多中心、回顾性观察性队列研究，纳入2000-01-01—2019-07-01在南方医科大学南方医院、南方医科大学顺德医院、佛山市第一人民医院以及赣州市人民医院4所中心置管并开始接受PD治疗的1 640例PD患者作为研究对象。对患者进行随访，随访截止时间为2021-07-01，终点事件为CVD死亡并记录患者生存时间及具体死亡原因。应用限制性立方条图（RCS）分析PNI与PD患者CVD死亡风险之间的非线性关联；采用Kaplan-Meier法绘制PD患者的生存曲线，绘制PNI预测PD患者CVD死亡的受试者工作特征（ROC）曲线，并根据最佳截断值（cut-off=40.46）将患者分为低PNI组703例与高PNI组937例；采用Log-rank检验和Cox风险回归模型分析探讨PNI对PD患者CVD死亡的影响。结果本研究中位随访时间为30个月，随访期间共148例患者死亡，其中CVD死亡73例（49.32%）。RCS结果表明，PNI与CVD死亡事件呈线性关联（P for Nonlinear=0.655）。ROC曲线显示，PNI预测PD患者CVD死亡的曲线下面积（AUC）为0.717（95%CI=0.659~0.775，P<0.001），灵敏度为74.0%，特异度为58.6%。Kaplan-Meier生存分析结果显示，低PNI组CVD生存率低于高PNI组（χ2=26.685，P<0.001）。多因素Cox风险回归模型分析，校正性别、年龄及CVD病史等混杂因素后，低PNI组仍是CVD死亡的独立预测因素（HR=7.76，95%CI=1.72~35.06，P=0.008），亚组分析结果仍稳健，无明显交互作用。结论 PNI降低是PD患者CVD死亡的独立影响因素，PD首年PNI评分在评估PD患者预后有一定的指导意义。

关键词: 慢性肾脏病, 腹膜透析, 预后营养指数, 心血管死亡, 预后, 队列研究, 回顾性研究, 影响因素分析

Abstract:

Background

Cardiovascular disease (CVD) is the primary cause of death in patients undergoing peritoneal dialysis (PD) , with malnutrition being one of the significant risk factors for both CVD and mortality. The prognostic nutritional index (PNI) serves as a comprehensive indicator of a patient's immune, inflammatory, and nutritional status. Due to its convenience and reliability, PNI has been widely used in prognostic assessments across various diseases, including cancer. Recent studies have indicated that PNI not only reflects the prognosis of PD patients but is also closely related to their cardiovascular health. However, the relationship between nutritional status at different time points and the prognosis of PD patients requires further exploration.

Objective

To explore the relationship between first-year PNI and CVD mortality in PD patients.

Methods

This multicenter, retrospective observational cohort study included 1 640 PD patients who initiated treatment between January 1, 2000, and July 1, 2019, at four medical centers: Nanfang Hospital, Southern Medical University, Shunde Hospital of Southern Medical University, the First People's Hospital of Foshan, and Ganzhou People's Hospital. Patients were followed up until July 1, 2021, with the primary endpoint being CVD mortality. A restricted cubic spline (RCS) was used to further examine the non-linear association between PNI and the risk of CVD mortality. Survival curves were generated using the Kaplan-Meier method, and receiver operating characteristic (ROC) curves for predicting CVD mortality based on PNI were analyzed, with an optimal cut-off of 40.46 dividing patients into low PNI (703 patients) and high PNI (937 patients) groups. The impact of PNI on CVD mortality was assessed using Log-rank tests and Cox regression analysis.

Results

The median follow-up period was 30 months, during which 148 patients died, 73 of whom from CVD (49.32%) . RCS results indicated a linear association between PNI and CVD mortality events (P for Nonlinear=0.655) . The area under the ROC curve (AUC) for PNI predicting CVD mortality was 0.717 (95%CI=0.659-0.775, P<0.001) , with a sensitivity of 74.0% and a specificity of 58.6%. Kaplan-Meier analysis showed statistically significant differences in CVD survival curves between the low and high PNI groups (χ²=26.685, P<0.001) . Multivariable Cox regression analysis, adjusted for gender, age, and history of CVD, indicated that a low PNI remains an independent predictor of CVD mortality (HR=7.76, 95%CI=1.72-35.06, P=0.008) . Subgroup analysis confirmed the robustness of these findings without significant interaction effects.

Conclusion

A reduced PNI is an independent factor influencing CVD mortality in PD patients, making the first-year PNI score a valuable tool for prognostic assessment in PD management.

Key words: Chronic kidney disease, Peritoneal dialysis, Prognostic nutritional index, Cardiovascular disease mortality, Prognosis, Cohort study, Retrospective study, Root cause analysis

朱露,艾军,廖生武,等. 预后营养指数对腹膜透析患者心血管疾病死亡的影响：一项多中心回顾性队列研究[J]. 中国全科医学, 2025, 28(05): 568-574. DOI: 10.12114/j.issn.1007-9572.2024.0340.
ZHU Lu,AI Jun,LIAO Shengwu, et al. Association of Prognostic Nutritional Index with Cardiovascular Mortality in Patients with Peritoneal Dialysis: a Multicenter Retrospective Cohort Study[J]. Chinese General Practice, 2025, 28(05): 568-574. DOI: 10.12114/j.issn.1007-9572.2024.0340.

图/表 5

图1 PNI评分与PD患者CVD死亡事件的非线性关联

Figure 1 Nonlinear association of PNI score with CVD mortality in patients with peritoneal dialysis

图2 PNI预测PD患者CVD死亡的ROC曲线

Figure 2 ROC curve of prognostic nutritional index and cardiovascular disease mortality in peritoneal dialysis patients

图3 高PNI组和低PNI组CVD死亡的Kaplan-Meier生存曲线注：PNI=预后营养指数，CVD=心血管疾病。

Figure 3 Kaplan-Meier survival curves for cardiovascular disease mortality in high-PNI group and low-PNI group

表1 PNI与PD患者CVD死亡的Cox回归分析

Table 1 Cox regression analysis of CVD mortality in patients with PNI and PD

自变量	模型1		模型2		模型3
自变量	HR（95%CI）	P值	HR（95%CI）	P值	HR（95%CI）	P值
高PNI组	1.00		1.00		1.00
低PNI组	3.62（2.15~6.11）	<0.001	4.15（2.18~7.89）	<0.001	7.76（1.72~35.06）	0.008

图4 两组PD患者CVD死亡的亚组分析森林图

Figure 4 Forest plot of subgroup analysis of cardiovascular disease mortality in two groups of patients with peritoneal dialysis

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预后营养指数对腹膜透析患者心血管疾病死亡的影响：一项多中心回顾性队列研究

Association of Prognostic Nutritional Index with Cardiovascular Mortality in Patients with Peritoneal Dialysis: a Multicenter Retrospective Cohort Study

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