Study on overhydration in dialysis patients and its association with inflammation

 Patients with chronic kidney disease receiving haemodialysis (HD) have permanent variations in hydration status that may affect their survival. 

 To analyse hydration status and body composition in patients on haemodialysis and its relation to inflammation. 

 We included 128 prevalent clinically stable patients on haemodialysis. We analysed body composition using spectroscopic bioimpedance and inflammation using blood parameters. 

 Patients with higher lean tissue had less intracellular (p=0.02) and extracellular water (p = 0.001). We did not find association with fat tissue and hydration. Mean overhydration was 7.5 %. We found an association between overhydration adjusted to extracellular water (OH/ECW) higher than 15 % similar to 10 %. They were both associated with low prealbumin levels (p = 0.001 and p = 0.05 respectively) and low levels of fat tissue (p = 0.001 and p = 0.05 respectively). 

 Overhydration defined as OH/ECW higher than 10 % and 15 % are related to low prealbumin levels and low fat tissue. We suggest decreasing the overhydration limit measured by bioimpedance to OH/ECW higher than 10 %.