Significant differences between two commonly used bioimpedance methods in hemodialysis patients

Area of Science:

• Nephrology
• Biomedical Engineering
• Clinical Measurement

Background:

• Bioimpedance analysis is crucial for fluid management in chronic hemodialysis patients.
• Accurate assessment of fluid volume, including intracellular water (ICW) and extracellular water (ECW), is vital.
• Several bioimpedance devices exist, necessitating comparative studies for clinical application.

Purpose of the Study:

• To compare the performance of two common bioimpedance devices, Body Composition Monitor (BCM) and InBody S10.
• To evaluate the interchangeability of BCM and InBody S10 in assessing body composition parameters in hemodialysis patients.
• To determine if measured differences impact clinical decisions, such as dry weight setting.

Main Methods:

• A cohort of 14 clinically stable chronic hemodialysis patients was recruited.
• Body composition was measured using BCM and InBody S10 devices just prior to hemodialysis.
• Key parameters assessed included total body water (TBW), ECW, ICW, lean tissue mass (LTM), and fat tissue mass.

Main Results:

• Statistically and clinically significant differences were found for all measured variables between BCM and InBody S10.
• InBody S10 overestimated TBW and ICW compared to BCM.
• BCM yielded higher measurements for LTM, fat mass, and ECW, with notable percentage differences for LTM (27%) and ICW (22%).

Conclusions:

• The discrepancies between BCM and InBody S10 are clinically significant.
• These devices cannot be used interchangeably for setting the dry weight in hemodialysis patients.
• Clinical practice requires careful consideration of the specific device used for body composition assessment.