P0184RISK PREDICTION FOR DEATH AND END-STAGE RENAL DISEASE DOES NOT PARALLEL REAL-LIFE TRAJECTORY OF OLDER PATIENTS WITH ADVANCED CHRONIC KIDNEY DISEASE - A ROMANIAN CENTER EXPERIENCE
Authors: Nastasa Andra , Apetrii Mugurel , Onofriescu Mihai , Nistor Ionut , Hussien Hani , Popa Cristina , Apascaritei Irina , Covic Adrian 
Published: June 2020

Abstract

Background and Aims
In Europe, the share of the elderly (≥65 years of age) in the total population is estimated to increase from 19.2% in 2016 to 29.1% by 2080. In 2016, European Renal Best Practice (ERBP) group published a clinical practice guideline on management of older patients with CKD stage3b or higher (eGFR&lt;45ml/min/1.73 m2). Two risk stratifications scores were emphasized: Bansal score for prognosticating risk of death in medium term, and Kidney Failure Risk Equation (KFRE) for estimating progression of CKD stage 3b or 4 to ESRD. Our group, as part of the ERBP team, aimed to evaluate and apply the framework proposed by the guideline, consisting of risk prediction for both mortality and progression to ESRD in a cohort of elderly patients with advanced CKD. After dividing the population in groups of risk, we described their real-life trajectory in terms of either reaching ESRD/death.

Method
In this retrospective cohort study we included patients aged ≥65 years with CKD stage 3b-4, evaluated at the Outpatient Nephrology Department of Dr. C. I. Parhon Hospital from Iași, Romania, between October 2016 – October 2018.
Individual risk for mortality was predicted using Bansal score, a nine-variable equation model. A total score of 7 (associated with a mortality risk of 53.82%) was established as cut-off value to differentiate between 2 groups: high risk of mortality (Bansal ≥ 7) and low risk of mortality (Bansal &lt; 7), given the fact that the ERBP guidelines don’t define a threshold for high risk in respect to mortality outcome.
According to the algorithm proposed by the guideline, individual risk for progression to ESRD at 5 years was calculated in the low mortality risk group, using the 4-variable Kidney Failure Risk Equation (KFRE).

Results
The final cohort included 958 patients, with a mean age of 74 years (SD: 7), and with similar gender distribution (50.6% female vs. 49.4% male).
Predicted trajectory in terms of reaching ESRD / death:
When we applied Bansal score for mortality, the total study population (N=958) was divided in two groups: N1 with high risk of mortality, which comprised more than half of the cohort (548 patients, 57.2%) and N2 with low risk of mortality (410 patients, 42.8%).
Individual risk of progression to ESRD was then estimated in N2 group, using 4-variable KFRE. Nearly ¾ of this group (75.4%, 309 subjects) presented a low-risk of progression and ¼ (24.6%, 101 subjects) had high-risk.
Real-life trajectory in terms of reaching ESRD / death:
From the entire cohort, 31 patients started renal replacement therapy (RRT) and 164 patients died as their first clinical event. The RRT initiation rate was 3.6% of N1 group (20 subjects) versus 2.7% of N2 group (11 subjects). The mortality rate was 15.5% of N1 group (85 deaths) versus 19.3% of N2 group (79 deaths). Figure 1 depicts the real-life trajectory of the population groups in terms of reaching ESRD / death.

Conclusion
In a large population from Eastern Europe, the application of the algorithm from the Clinical Practice Guideline on management of older patients with advanced CKD showed that risk prediction for death and end-stage renal disease does not parallel the real-life trajectory of the population. More than half of the subjects had a high risk of mortality, however we found similar death rates in the 2 groups (high versus low risk of mortality). Also, the RRT initiation rates were similar, irrespective of predicted mortality risk or kidney failure risk, suggesting that implementing the guideline in real-life settings is still a challenge.