生物电阻抗分析法与CT对肿瘤恶病质的预测价值

Predictive value of bioelectrical impedance analysis and CT in cancer cachexia

目的研究生物电阻抗分析法(bioelectrical impedance analysis,BIA)和CT相关指标与肿瘤恶病质的关系,探讨二者对肿瘤恶病质的预测价值。方法选取2022年8月至2023年9月在山西白求恩医院肿瘤科住院的肿瘤患者为研究对象,于入院后48 h内通过BIA获取其体成分相关指标,包括全身相位角(PhA)、去脂体重(FFM)、基础代谢率(BMR)、骨骼肌指数(SMI)、内脏脂肪面积(VFA)等。通过MIM计划系统勾画出患者腹部CT图像中第3腰椎中点横截面脂肪和骨骼肌的边界,半自动化得出相关参数,包括CT骨骼肌指数(CT-SMI)和CT脂肪质量指数(CT-FMI)等。使用t检验或χ^(2)检验比较恶病质组和非恶病质组基本信息和营养指标的差异,采用单因素Logistic回归分析各指标与恶病质发生的关系,通过ROC曲线判定二者对肿瘤恶病质的预测价值,采用R4.2.0中的predictABEL包计算综合判别改善指数(IDI)和净重新分类指数(NRI)。结果本研究共纳入100例肿瘤患者,其中恶病质组53例,非恶病质组47例。两者相比较,恶病质组男性患者占比较较高,PhA、BMI、FFM、BMR、SMI、VFA、CT-SMI、CT-FMI等指标均低于非恶病质组,差异具有统计学意义(P<0.05)。单因素Logistic回归分析结果显示男性和较低的PhA、BMI、FFM、BMR、SMI、VFA、CT-SMI、CT-FMI是肿瘤患者发生恶病质的危险因素。ROC曲线图结果表明BIA与CT对肿瘤恶病质均有良好的预测价值,相较于CT-SMI,BIA测量的SMI预测恶病质的IDI为0.031[95%CI(-0.011,0.073)],NRI为-0.080[95%CI(-0.241,0.081)],反映BIA对恶病质的诊断效能并未优于CT,但不劣于CT。结论PhA、BMI、FFM、BMR、SMI、VFA、CT-SMI、CT-FMI等指标的下降是肿瘤恶病质的危险因素,且男性肿瘤患者似乎更易合并恶病质。CT与BIA评估机体肌肉与脂肪水平方面效能相近,二者均可用于预测肿瘤恶病质。

Objective To evaluate the association between indicators of bioelectrical impedance analysis(BIA)and CT-realated indices and cancer cachexia in patients,and explore the predictive value.Methods Patients with cancer in the oncology department of Shanxi Bethune Hospital in Taiyuan were selected from August 2022 to September 2023.Their body composition-related indices,including whole-body phase angle(PhA),fat free mass(FFM),basal metabolic rate(BMR),skeletal muscle index(SMI),and visceral fat area(VFA),were obtained by BIA within 48 h of admission to the hospital.The MIM planning system was used to delineate the boundaries of fat and skeletal muscle in the mid-point cross-section of the third lumbar vertebra in the abdominal CT images of the patients,providing semi-automated relevant parameters,including CT-skeletal muscle index(CT-SMI)and CT-fat mass index(CT-FMI).Differences in basic information and nutritional indicators between the cachexia and non-cachexia groups were compared using the t test orχ^(2) test,the relationship between each indicator and the occurrence of malignant disease was analyzed using univariate Logistic regression,the predictive value of the two for tumor malignancy was determined by the ROC curve,and the integrated discrimination improvement(IDI)and net reclassification improvement(NRI)were calculated using the predictABEL package in R 4.2.0 Results A total of 100 cases were included,in which 53 cases of cachexia group,47 cases of non-cachexia group.Compared with the two groups,cachexia group had a higher percentage of male patients.PhA,BMI,FFM,BMR,SMI,VFA,CT-SMI and CT-FMI in cachexia group were lower than those in non-cachexia group,and the differences were statistically significant(P﹤0.05).Univariate Logistic regression analysis showed that male and the decline of PhA,BMI,FFM,BMR,SMI,VFA,CT-SMI and CT-FMI were the risk factors for cachexia in tumor patients.The ROC curve showed that both BIA and CT had good predictive value for cancer cachexia.Compared with CT-SMI,the IDI of SMI measured by BIA for predicting cachexia was 0.031[95%CI(-0.011,0.073)],and the NRI was-0.080[95%CI(-0.241,0.081)],reflecting that the diagnostic efficacy of BIA for cachexia was not superior to that of CT,but was not inferior to that of CT.Conclusion The decrease of PhA,FFM,BMR,SMI,VFA,CT-SMI and CT-FMI were related risk factors for cancer cachexia.Male tumor patients seemed to be more likely to be complicated with cachexia.CT and BIA had similar efficacy in evaluating the body's muscle and fat levels,and both of them can be used to predict cancer cachexia.