Cancer patients suffer from metabolic and pathophysiological changes that contribute to malnutrition. These metabolic changes lead to loss of cell integrity, which induces dehydration intracellular and increase extracellular fluid. Bioelectrical impedance analysis (BIA)-derived phase angle (PhA) is considered a good tool to evaluate hydration status, but in cancer patients it is not fully elucidated. Thus, in cancer patients the aims of this study were to (1) verify the association between PhA and fatigue, (2) verify the association between PhA and fatigue after adjustment for extracellular fluid accumulation, and (3) assess the prevalence of fatigue. This cross-sectional study was conducted with 124 patients of both genders on cancer treatment. Body weight, height, body mass index, handgrip strength, performance status, and cachexia were collected. In addition, body composition was evaluated by BIA to obtain hydration status and PA. The cut-off point used to classify patients with low PhA was set <4°. To identify fatigue, the Functional Assessment of Cancer Therapy Fatigue questionnaire was applied. Of the 124 patients evaluated (n = 98/79% men), 26% had fatigue. The prevalence of fatigue was higher in patients with lower PhA <4° (65.63%). In the logistic regression analyses, we found that patients with PhA >4° had lower risk for fatigue (OR: 0.92 95% CI [0.86-0.99], p = 0.03) in the crude model, however after adjustments by weight loss percentage in 6 months, age, sex, and hydration the association was not maintained (OR: 0.94 95% CI [0.85-1.04], p = 0.26). In conclusion, we found that ~26% of cancer patients have fatigue. In spite of adjustment for extracellular fluid, PhA is not associated with fatigue. The importance of measuring PhA to assess intra and extracellular hydration in cancer patients is highlighted.

中文翻译：

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相角与癌症患者的疲劳无关：水合作用。

癌症患者患有导致营养不良的代谢和病理生理变化。这些代谢变化导致细胞完整性丧失，从而引起细胞内脱水并增加细胞外液。生物电阻抗分析（BIA）派生的相角（PhA）被认为是评估水合作用状况的好工具，但在癌症患者中并未得到充分阐明。因此，在癌症患者中，本研究的目的是（1）验证PhA与疲劳之间的关联；（2）验证调整细胞外液积聚后的PhA与疲劳之间的关联；（3）评估疲劳的患病率。这项横断面研究是针对124位性别不同的癌症患者进行的。体重，身高，体重指数，握力，运动状态，和恶病质被收集。另外，通过BIA评估身体组成以获得水合状态和PA。用于对低PhA的患者进行分类的临界点设置为<4°。为了识别疲劳，应用了癌症治疗疲劳功能问卷。在评估的124位患者中（男性= 98/79％），有26％患有疲劳。PhA <4°较低的患者中疲劳发生率较高（65.63％）。在逻辑回归分析中，我们发现PhA> 4°的患者在粗模型中的疲劳风险较低（OR：0.92 95％CI [0.86-0.99]，p = 0.03），但是在按体重减轻百分比进行调整后6个月，年龄，性别和水合作用没有得到维持（OR：0.94 95％CI [0.85-1.04]，p = 0.26）。总之，我们发现约26％的癌症患者患有疲劳。尽管可以调节细胞外液，但PhA与疲劳无关。强调了测量PhA来评估癌症患者体内和细胞外水合作用的重要性。