Borges GLS, Mendes LR, Trombim IC, Goes CR, Vogt BP. Bioelectrical impedance analysis for assessing hydration status in patients undergoing maintenance hemodialysis. World J Nephrol 2026; 15(2): 118360 [DOI: 10.5527/wjn.v15.i2.118360]
Corresponding Author of This Article
Barbara P Vogt, PhD, Adjunct Professor, Nutrition, Federal University of Uberlândia, Avenida Pará 1720, Umuarama Campus, Uberlandia 38405-320, Minas Gerais, Brazil. barbaravogt@ufu.br
Research Domain of This Article
Urology & Nephrology
Article-Type of This Article
research-article
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This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
World J Nephrol. Jun 25, 2026; 15(2): 118360 Published online Jun 25, 2026. doi: 10.5527/wjn.v15.i2.118360
Bioelectrical impedance analysis for assessing hydration status in patients undergoing maintenance hemodialysis
Geovanna L S Borges, Luana R Mendes, Isadora C Trombim, Cassiana R Goes, Barbara P Vogt
Geovanna L S Borges, Luana R Mendes, Isadora C Trombim, Barbara P Vogt, Nutrition, Federal University of Uberlândia, Uberlandia 38405-320, Minas Gerais, Brazil
Cassiana R Goes, Nutrition, Federal University of Viçosa, Rio Paranaíba 38810-000, Minas Gerais, Brazil
Co-first authors: Geovanna L S Borges and Luana R Mendes.
Author contributions: Borges GLS contributed to visualization; Borges GLS, Mendes LR, and Vogt BP contributed to formal analysis, interpretation of data, writing - original draft; Trombim IC contributed to data acquisition; Trombim IC and Goes CR contributed to writing - review and editing; Goes CR and Vogt BP contributed to design of the work, supervision; Borges GLS and Mendes LR contributed equally to this manuscript and are co-first authors. All authors have approved this submission, read and approved the final manuscript.
Institutional review board statement: This study protocol was reviewed and approved by the Research Ethics Committee of the Federal University of Uberlandia. The procedures used in this study adhere to the tenets of the Declaration of Helsinki.
Informed consent statement: All study participants provided their informed written consent to participate prior to study enrollment.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Data sharing statement:
The datasets generated and/or analyzed during the current study are available from the corresponding author upon reasonable request.
Corresponding author: Barbara P Vogt, PhD, Adjunct Professor, Nutrition, Federal University of Uberlândia, Avenida Pará 1720, Umuarama Campus, Uberlandia 38405-320, Minas Gerais, Brazil. barbaravogt@ufu.br
Received: January 6, 2026 Revised: February 4, 2026 Accepted: March 9, 2026 Published online: June 25, 2026 Processing time: 167 Days and 6.7 Hours
Abstract
BACKGROUND
Adequate hydration status is a concern in patients receiving hemodialysis, as fluid overload increases the risk of complications and mortality. Fluid overload in this population is associated with complications, including arterial hypertension, intradialytic hypotension, pulmonary and peripheral edema, cardiovascular events, reduced body mass index, malnutrition, and increased mortality. Several methodologies have been proposed to evaluate hydration status in hemodialysis patients using indices derived from Bioelectrical impedance analysis parameters.
AIM
To assess the hydration status of patients receiving hemodialysis using different indices.
METHODS
Patients receiving hemodialysis for at least 3 months were included. Hydration status was evaluated before and after the hemodialysis session. The data provided by bioelectrical impedance analysis were total body water (TBW), intracellular water, and extracellular water (ECW). Fluid overload [overhydration (OH)] was calculated. Hydration status was classified according to the three indices: OH, OH/ECW, and ECW/body weight. Interdialytic weight gain (IDWG) and blood pressure (BP) were collected. N-terminal pro-brain natriuretic peptide were measured before and after the hemodialysis.
RESULTS
A total of 54 patients were evaluated, with mean age of 57.6 ± 13.1 years, 59.3% male. Before hemodialysis session, 23 patients were classified as having fluid overload, identified by at least one of the indices. IDWG and ECW showed significant positive correlation with all evaluated indices. BP, TBW, and intracellular water correlated only with the OH and OH/ECW indices. After hemodialysis session, 5 patients were identified with fluid overload by the OH and ECW/body weight indices. ECW was the only parameter that showed correlation with all indices. N-terminal pro-brain natriuretic peptide correlated with the OH and ECW/body weight indices. BP, IDWG, and TBW remained correlated with OH and OH/ECW.
CONCLUSION
The OH index identified a greater number of patients with fluid overload and showed better correlation with hydration parameters provided by the bioelectrical impedance analysis.
Core Tip: Adequate hydration status is a concern in patients undergoing hemodialysis, as fluid overload increases the risk of complications and mortality. In our study, we evaluated hydration status before and after the hemodialysis session using data provided by bioelectrical impedance. Hydration status was classified according to the three indices: Overhydration (OH), OH/extracellular water, and extracellular water/body weight. The OH index was the most effective in detected more patients with fluid overload before and after the dialysis session, showed better correlation with hydration parameters provided by bioimpedance, blood pressure, and N-terminal pro-brain natriuretic peptide.
