#1097 Linking changes in individual performance scores to survival outcomes in chronic hemodialysis patients
Authors: Santos Carla , Lucas Carlos , Silva Eliana , Haarhaus Mathias , Macário Fernando 
Published: May 2024

Abstract

Background and Aims
Chronic kidney disease (CKD) management has advanced significantly over recent years, yet mortality rates among hemodialysis (HD) patients remain high. This study aims to assess the impact of changes in an individualized patient performance score (IPPS) on survival in a large cohort of HD patients.

Method
This multicentre, observational, prospective cohort study included HD patients across 19 countries, starting from January 1st, 2022. We followed these patients for one year, categorizing them based on their survival status at year's end. We calculated the mean IPPS monthly, from June to December 2021, and divided the patients into tertiles based on their December 2021 scores. Subsequently, we formed five groups based on their IPPS dynamics over six months. We used Kaplan-Meier and Cox regression analyses to evaluate survival, presenting the results as hazard ratios (HR) and 95% confidence intervals (95% CI). A p-value below 0.05 was considered statistically significant. The IPPS, ranging from 0 to 100, was calculated based on eight key performance areas, with higher scores indicating better medical performance: Vascular Access (20 points): type of vascular access, episodes of thrombosis and infection); HD adequacy (20 points): eKt/V, blood flow and treatment time; Anemia (20 points): hemoglobin concentration, transferrin saturation, ferritin; Arterial hypertension (10 points): mean arterial pressure; Mineral Bone disease (15 points): iPTH, plasmatic phosphorus and calcium; Fluid status (5 points): percentage of interdialytic fluid gain; Nutrition (5 points): plasmatic albumin and phosphorus and Others (5 points): influenzae vaccination, transplantation status and hospitalization events. The final score is obtained by the weighted sum of positive clinical factors, subtracted from the weighted sum of negative clinical factors and is reported as a number ranging from 0 to 100, with a higher score representing a better medical performance.

Results
The study included 10 458 HD patients. In the survival analysis, a significant reduction in mortality odds was observed in patients with a stable IPPS of 72 or lower, compared to those with a score consistently above 86. Patients transitioning from the lowest to the highest tertile in six months had a mortality HR similar to those consistently in the highest tertile. On the other hand, patients showing an improvement in IPPS score from the lowest to the highest tertile in the same period had a mortality HR similar to the intermediate group (Table 1).

Conclusion
A lower total IPPS score (&lt;72) was associated with a threefold increase in mortality risk compared to scores above 86. An increase in IPPS from the lowest to the highest tertile correlated with a significant reduction in mortality, equating to the survival rates of patients consistently scoring high. These findings underscore the potential of IPPS as a valuable tool for guiding clinical interventions in the HD population to enhance patient survival.