Objective: Residual kidney function (RKF) is a strong marker of the remaining capacity of the kidneys in patients with end-stage renal disease (ESRD). The fact that RKF declines in the first year of hemodialysis (HD) has drawn more attention recently. The aim of this study was to determine and analyze the current RKF level and related factors in patients undergoing HD treatment.
Materials and Methods: The study was performed at Kars State Hospital with 73 HD patients. Residual renal urea clearance (KRU) was measured to determine RKF. Patient urine volume was determined during the period between the end of the first HD session of the week and the beginning of the next HD session. The patients were classified into 3 groups according to KRU level: <1, 1-2, and >2 mL/minute. The duration of HD treatment, biodemographic characteristics, biochemical and hormonal analyses, HD adequacy, ESRD etiology, and co-morbidities were compared between groups. A p value of less than 0.05 was considered statistically significant (confidence interval: 95%).
Results: There was a statistically significant difference between the KRU value and the duration of HD treatment (p<0.001), ESRD etiology (p=0.037), serum potassium level (p=0.028), phosphorus level (p=0.036), urine volume (p<0.001), ultrafiltration (UF) volume (p=0.002), and body mass index (p=0.002). Patients with a urine volume of <100 mL/day had a longer duration of HD treatment of 6.9±4.2 years (p=0.021), as well as a greater quantity of UF administered 723±230 mL/hour (p<0.001).
Conclusion: Rather than provide an explanation of a cause-effect relationship for RKF loss, the findings of this study may contribute to the monthly interpretation and regulation of HD therapy. Additional studies that include RKF measurement at certain time intervals and long-term observation are needed.