Fluid status in peritoneal dialysis patients: the European Body Composition Monitoring (EuroBCM) study cohort

Abstract

Background: Euvolemia is an important adequacy parameter in peritoneal dialysis (PD) patients. However, accurate tools to evaluate volume status in clinical practice and data on volume status in PD patients as compared to healthy population, and the associated factors, have not been available so far.

Methods: We used a bio-impedance spectroscopy device, the Body Composition Monitor (BCM) to assess volume status in a cross-sectional cohort of prevalent PD patients in different European countries. The results were compared to an age and gender matched healthy population.

Results: Only 40% out of 639 patients from 28 centres in 6 countries were normovolemic. Severe fluid overload was present in 25.2%. There was a wide scatter in the relation between blood pressure and volume status. In a multivariate analysis in the subgroup of patients from countries with unrestricted availability of all PD modalities and fluid types, older age, male gender, lower serum albumin, lower BMI, diabetes, higher systolic blood pressure, and use of at least one exchange per day with the highest hypertonic glucose were associated with higher relative tissue hydration. Neither urinary output nor ultrafiltration, PD fluid type or PD modality were retained in the model (total R² of the model = 0.57).

Conclusions: The EuroBCM study demonstrates some interesting issues regarding volume status in PD. As in HD patients, hypervolemia is a frequent condition in PD patients and blood pressure can be a misleading clinical tool to evaluate volume status. To monitor fluid balance, not only fluid output but also dietary input should be considered. Close monitoring of volume status, a correct dialysis prescription adapted to the needs of the patient and dietary measures seem to be warranted to avoid hypervolemia.

Conflict of interest statement

Competing Interests: Adelheid Gauly, Rainer Himmele, Volker Schoder and Peter Wabel are employees of Fresenius Medical Care. Wim Van Biesen received speaker's fees from Fresenius Medical Care, Baxter and Gambro on different occasions, however none related to the current study. Stanley Fan received speaker's fees from Fresenius Medical Care and Baxter on different occasions, however none related to the current paper. His department received educational and research support grants from Baxter and Fresenius, but none related to the current study. Adrian Covic and John Williams have worked as consultants for Fresenius Medical Care. There are no patents, products in development or marketed products to declare. This does not alter the authors' adherence to all the PLoS ONE policies on sharing data and materials, as detailed online in the guide for authors.

Figures

Figure 1. Scatter plot of the relation between absolute Δtissue hydration (litres) in the X-axis and systolic blood pressure (mmHg) in the Y-axis in the individual patients of the EuroBCM study cohort.

Dotted vertical lines indicate the 10th and 90th percentile of absolute Δtissue hydration in the healthy population (−1.1 and +1.1 liter respectively), representing thus the limits of “normohydration”. Dotted horizontal lines indicate the “normotensive range” for systolic blood pressure.

Figure 2. Box and whisker plots (median, 25th and 75th quartile, outliers) of Absolute ΔTissue Hydration (in liters) in the different transport categories.

n.d.: no peritoneal transport characteristics available in the 4 months before the BCM measurement.