Nonstandardized High-Intensity Dialysis Dose Improves Survival in Patients With End-Stage Renal Disease

Introduction One of the most important critical determinants of quality of life and adequacy of hemodialysis (HD) performed in patients is the recorded survival and mortality rates. Nowadays, as an adequately performed HD dialysis, we accept the one with reaching values for the index single pool Kt/V (spKt/V) higher than 1.2. In recent years, more intensive HD regimens with spKt/V≥1.5 have been increasingly discussed, which can significantly improve patient survival. However, their benefit has yet to be proven, as extremely high spKt/V values can be misleading as they may result from malnutrition leading to reduced survival and increased relative risk of death. The aim of this study is to present to the community the impact of nonstandardized high dialysis doses (spKt/V>1.5) on annual survival and mortality rates in the dialysis population and to explore new strategies for enhancing quality of life and survival, as well as to promote their regular implementation in clinical practice and personalized patient care. Material and methods The present retrospective study was conducted at the Clinic of Nephrology and Dialysis at University Hospital St. Marina in Varna, Bulgaria for a period of five years. It involved a survival analysis of 100 dialysis patients who met the inclusion and exclusion criteria. The dialysis dose delivered was the criterion for their allocation into three studied groups: Group 1 with adequate dose (standardized) - spKt/V = 1.2-1.49, Group 2 with high dose (nonstandardized) - spKt/V≥1.5, and Group 3 with inadequate dose (low) - spKt/V≤1.19. We recorded total annual mortality and survival rates, analyzing their relationship with the delivered dialysis dose and assessing the relative risk of death and expected survival. Results The analysis results indicated that high-intensity regimens with an spKt/V≥1.5 were linked to a better patient prognosis, with a significantly lower risk of death compared to standard regimens and increased survival expectancy. Data from the survival analysis suggested that the long-term impact of increasing the dialysis dose (spKt/V≥1.5) on survival becomes evident after the third year. Additionally, nutritional status parameters emerged as key risk factors for deterioration, along with the indicators of dialysis adequacy. Discussion Improved survival rates have been observed in patients undergoing nocturnal HD. In the latter, significantly higher spKt/V values have been achieved due to extended dialysis sessions, as well as in those performing dialysis at home. Despite concerns about possible misinterpretation of extremely high spKt/V values (>1.5) as a sign of malnutrition when urea volume of distribution is reduced, it is found that when only urea clearance (Kt) is used, without volume counts, the risk of death decreases by 2% for each liter increase in clearance. This demonstrates that the assessment of dialysis adequacy is a much broader concept than the values of generally accepted indicators and should be focused on individualized care and risk assessment tailored to each patient. Conclusions We believe that the modern nephrological community should strive to achieve a high dialysis dose (spKt/V≥1.5) to improve clinical outcomes and patient prognosis. Assessing dialysis adequacy is complex and goes beyond a simple numerical value such as spKt/V. It requires careful monitoring of nutritional status and the management of all HD-related complications.