Effect of Strict Volume Control on Renal Progression and Mortality in Non-Dialysis-Dependent Chronic Kidney Disease Patients: A Prospective Interventional Study

Objective: The aim of this study was to examine the effect of volume status on the progressions of renal disease in normovolemic and hypervolemic patients with advanced non-dialysis-dependent chronic kidney disease (CKD) who were apparently normovolemic in conventional physical exam­ination. Materials and Methods: This was a prospective interventional study performed in a group of stage 3–5 CKD patients followed up for 1 year. Three measurements were made for volume and renal status for every patient. The fluid status was assessed by a bioimpedance spectroscopy method. A blood pressure (BP) value > 130/80 mm Hg prompted the initiation or dose increment of diuretic treatment in normovolemic patients. Result: Forty-eight patients (48%) were hypervolemic. At the end of the 1-year follow-up, hypervolemic patients were found to have a significantly lower estimated glomerular filtration rate and higher systolic BP compared to baseline. Hypervolemia was associated with an increased incidence of death. Conclusion: We have shown that maintenance of normovolemia with diuretic therapy in normovolemic patients was able to slow down and even improve the progression of renal disease. Volume overload leads to an increased risk for dialysis initiation and a decrease in renal function in advanced CKD. Volume overload exhibits a stronger association with mortality in CKD patients.