Extracellular water/total body water ratio as predictor of mortality in hemodialysis patients

• Published in: Renal failure 2021-01, Vol.43 (1), p.821-829
• Main Authors: Pérez-Morales, Rosa, Donate-Correa, Javier, Martín-Núñez, Ernesto, Pérez-Delgado, Nayra, Ferri, Carla, López-Montes, Aurora, Jiménez-Sosa, Alejandro, Navarro-González, Juan Francisco
• Format: Article
• Language: English
• Subjects: Aged; Aged, 80 and over; Bioimpedance; Body composition; Body water; Body Water - physiology; Cardiovascular diseases; Cardiovascular Diseases - mortality; Cause of Death; Clinical Study; ECW/TBW; Electric Impedance; Extracellular Space - physiology; Female; Hemodialysis; Humans; Logistic Models; Male; Middle Aged; Mortality; overhydration; Predictive Value of Tests; Proof of Concept Study; Prospective Studies; Renal Dialysis; Spectroscopy; Water-Electrolyte Imbalance - diagnosis; Water-Electrolyte Imbalance - physiopathology
• ISSN: 0886-022X; 1525-6049
• DOI: 10.1080/0886022X.2021.1922442

Overhydration is a predictor of mortality in hemodialysis (HD) patients. Bioimpedance spectroscopy (BIS) is used to determine the body composition. Extracellular Water/Total Body Water (ECW/TBW) ratio has been proposed to predict mortality. Multicenter, prospective, observational, proof-of-concept study to estimate the impact of ECW/TBW in global and cardiovascular mortality and the relationship with cardiovascular biomarkers. The study included 60 patients (mean age, 71.8 ± 11.4 years; mean time on HD, 52.3 ± 30.8 months) with a median follow-up of 30.5 months (IQ range, 17.2-34 months). Post-dialysis ECW/TBW was directly associated with NT-proBNP and cTnT. During the study 28 patients died, most of them (43%) due to cardiovascular events. Compared to the survivors, these subjects had a higher post-dialysis ECW/TBW ratio (p = 0.006), while for cardiovascular mortality the only significant difference was a higher pre-dialysis ECW/TBW. The ability of post-dialysis ECW/TBW ratio to predict all-cause mortality had an area under the ROC curve (AUC) of 0.71 (CI 95%, 0.57-0.81; p = 0.002), with a cutoff point of 0.5023. For cardiovascular mortality the AUC was 0.66 (CI 95%, 0.52-0.77; p = 0.045), with a cutoff point of 0.4713. The post-dialysis ECW/TBW ratio measured by BIS can be a predictor of all-cause and cardiovascular mortality.