Toso Silvia, Piccoli Antonio, Gusella Milena, Menon Daniela, Crepaldi Giorgio, Bononi Antonio, Ferrazzi Eros
Division of Medical Oncology, General Hospital, via Tre Martiri, I-45100 Rovigo, Italy.
Nutrition. 2003 Jun;19(6):510-4. doi: 10.1016/s0899-9007(02)01084-5.
Bioelectrical impedance vector analysis allows non-invasive evaluation of soft tissue hydration and mass through pattern analysis of vector plots as height, normalized resistance, and reactance measurements.
Whole-body impedance measurements were made with a single frequency (50 kHz) analyzer (BIA-101, Akern/RJL Systems) in 148 adult, white, male subjects 45 to 85 y old: 56 healthy control subjects, 31 cancer patients after surgical procedure (without disease), and 61 patients with locally advanced (30 patients) or disseminated (31 patients) disease with the same body mass index and age. All patients were free from antineoplastic treatment and active nutritional intervention.
Mean vectors of cancer groups without disease and locally advance disease versus the control group were characterized by a comparable normalized resistance component with a reduced reactance component (separate 95% confidence limits, P < 0.05), indicating a comparable ionic conduction (hydration) with loss of dielectric mass (cell membranes and tissue interfaces) of soft tissues. Overlapping 95% confidence limits of their mean vectors indicated comparable electrical tissue properties in less versus more advanced disease.
Monitoring vector displacement trajectory toward the reference target vector position may represent useful feedback in support therapy planning of individual patients.
生物电阻抗矢量分析可通过对矢量图（如身高、归一化电阻和电抗测量值）进行模式分析，对软组织水合作用和质量进行无创评估。
使用单频（50kHz）分析仪（BIA - 101，Akern/RJL Systems）对148名45至85岁的成年白人男性受试者进行全身阻抗测量：56名健康对照受试者，31名手术后无疾病的癌症患者，以及61名患有局部晚期（30名患者）或播散性（31名患者）疾病的患者，这些患者具有相同的体重指数和年龄。所有患者均未接受抗肿瘤治疗且未进行积极的营养干预。
无疾病的癌症组和局部进展期疾病组与对照组的平均矢量特征为，归一化电阻分量相当，电抗分量降低（95%置信限分别计算，P < 0.05），表明离子传导（水合作用）相当，但软组织的介电质量（细胞膜和组织界面）有所损失。它们平均矢量的95%置信限重叠，表明疾病程度较轻与较重的患者电组织特性相当。
监测矢量向参考目标矢量位置的位移轨迹可能为个体患者的支持性治疗计划提供有用的反馈。
