Yang Jiongxian, Zhang Jie, Liu Jun, Liu Gang, Qian Suyun
Department of Health Care Center, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China.
Department of Pediatric Intensive Care Unit, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health, Beijing, China.
Front Nutr. 2024 Aug 19;11:1359814. doi: 10.3389/fnut.2024.1359814. eCollection 2024.
Phase angle (PhA) is a variable obtained from bioelectrical impedance analysis (BIA). It is highly sensitive and specific and is commonly used in clinical nutrition assessment. Recently, PhA has shown promise in predicting clinical outcomes, especially as a new indicator of mortality, but its use in pediatric research is limited. This study aims to investigate the association between PhA measured at admission using BIA and PICU length of stay (LOS) and 60-day mortality in critically ill children and adolescents.
A consecutive series of pediatric patients in the PICU underwent BIA measurements within 72 h of admission. All patients met the inclusion and exclusion criteria. Patient demographics, anthropometric measurements, pediatric index of mortality 2 score (PIM-2), and laboratory exams were recorded. Kaplan-Meier (K-M) survival curves were constructed based on the critical PhA value to assess differences in survival status within the 60-day window. Multivariate cox regression model was employed to illustrate the relationship between PhA and 60-day mortality rates. The Youden's index method was used to identify the critical cut-off value for PhA in relation to mortality rates. ROC curves provided the area under the curve (AUC) and a 95% confidence interval (CI).
A total of 205 pediatric patients (118 boys) were included, with a mean age of 9.2 years (±6.0). Survival curves indicated a cutoff value of 3.1°, with higher survival in patients with PhA ≥3.1° compared to those with PhA <3.1° ( = 10.51, < 0.0001). The area under the ROC curve was 0.70, with a sensitivity of 0.65 and specificity of 0.72. Total hospital LOS was longer in the PhA <3.1° group compared to the PhA ≥3.1° group ( = 0.000). The PhA <3.1° group had a longer PICU LOS (adjusted for age and sex, HR 1.871, = 0.000, log-rank test, = 0.000). PhA and PIM-2 were two independently significant correlated variables ( < 0.05) for the 60-day mortality rate in this study.
Low PhA in patients is associated with longer PICU LOS and an increased risk of PICU patient mortality. PhA not only serves as an indicator for monitoring pediatric nutrition but also as a prognostic indicator for PICU patients.
相角（PhA）是通过生物电阻抗分析（BIA）获得的一个变量。它具有高度的敏感性和特异性，常用于临床营养评估。最近，相角在预测临床结局方面显示出前景，尤其是作为一种新的死亡率指标，但其在儿科研究中的应用有限。本研究旨在调查入院时使用BIA测量的相角与危重症儿童和青少年在儿科重症监护病房（PICU）的住院时间（LOS）以及60天死亡率之间的关联。
连续纳入PICU的儿科患者，在入院72小时内进行BIA测量。所有患者均符合纳入和排除标准。记录患者的人口统计学信息、人体测量数据、儿科死亡率指数2评分（PIM - 2）以及实验室检查结果。基于临界相角值构建Kaplan - Meier（K - M）生存曲线，以评估60天观察期内生存状态的差异。采用多变量Cox回归模型来说明相角与60天死亡率之间的关系。使用约登指数法确定与死亡率相关的相角临界截断值。ROC曲线提供曲线下面积（AUC）和95%置信区间（CI）。
共纳入205例儿科患者（118例男孩），平均年龄9.2岁（±6.0）。生存曲线表明临界值为3.1°，相角≥3.1°的患者生存率高于相角<3.1°的患者（χ² = 10.51，P < 0.0001）。ROC曲线下面积为0.70，敏感性为0.65，特异性为0.72。相角<3.1°组的总住院时间比相角≥3.1°组更长（P = 0.000）。相角<3.1°组的PICU住院时间更长（校正年龄和性别后，HR 1.871，P = 0.000，对数秩检验，P = 0.000）。在本研究中，相角和PIM - 2是与60天死亡率两个独立显著相关的变量（P < 0.05）。
患者相角低与PICU住院时间延长及PICU患者死亡风险增加相关。相角不仅可作为监测儿科营养的指标，还可作为PICU患者的预后指标。
