#511 Inadequate diagnostic investigations and low treatment rates in CKD anemia: an inertia that can only change with long-term follow-up
Authors: Kurak Çiğdem Kara , Karlık Sarenur , Hayran Mutlu , Haberal Güldehan , Erdut Arda , Yeter Hasan Hacı , Yildirim Tolga , Yilmaz Şeref Rahmi , Altun Bulent , Erdem Yunus , Arici Mustafa 
Published: May 2024

Abstract

Background and Aims
Anemia is observed from the early stages in the course of chronic kidney disease (CKD), and as the stage progresses, the severity of anemia and its impact on quality of life increase. Early diagnosis of anemia in chronic kidney disease, assessments related to its etiology, and treatment are therefore crucial. There is no comprehensive and long-term study in Turkey addressing the diagnostic and therapeutic management of anemia seen in the course of chronic kidney disease. The aim of this study is to investigate the frequency of anemia in different stages of CKD in patients diagnosed with Stage 3 and more advanced stages, to evaluate the effectiveness of diagnostic approaches, and management of iron parameters and anemia, and to investigate the effect of anemia on patient survival. We aim to present “real-life” data from this study to guide clinical practice and correct errors or deficiencies in anemia management.

Method
This study is a single-center, observational-descriptive retrospective study. 1321 outpatients with Stage 3A and advanced CKD and anemia who admitted to Hacettepe University Faculty of Medicine Nephrology Clinic between 2014 and 2018 were included in the study. Data for demographics, CKD etiologies and stages, anemia severities, comorbid diseases were collected from electronic health system (Table 1). Diagnostic investigations for anemia evaluation and therapeutic interventions such as administration of iron, folic acid, vitamin B12, erythropoiesis stimulating agents (ESA) were assessed. The long-term yield of diagnostic and therapeutic approaches and their effects on survival were also evaluated. The study investigated whether the severity of anemia and improvement in anemia had an effect on survival.

Results
Ferritin is the most commonly performed test for the etiology of anemia (76.4%). Request rates for tests such as B12, folic acid, transferrin saturation and reticulocyte are below 20%. More than half of the patients with anemia (59.4%) have not received any form of anemia treatment. Even among those whose ferritin test was checked and the value was &lt;100 µg/dL, only 41.4% were given iron treatment. As the clinical follow-up period of the patients increased, it was observed that anemia treatment was applied better and target values were reached more frequently (p &lt; 0.001). More than one third of the patients (34.8%) died during follow-up. The overall survival in patients whose anemia improved was 79.8%, and it was 62.8% in patients whose anemia did not improve the overall survival was (p = 0.002) (Fig. 1). When examining the relationship between survival status and anemia severity for the non-dialysis-dependent CKD Stage 3-5 group, there was a statistically significant survival difference between the Hb group of 10-11.9 g/dL to Hb group of &lt;10 g/dL (p = 0.004).

Conclusion
This study has shown that diagnostic tests for etiology of anemia were insufficiently ordered. It was also found that a significant majority of anemic patients who underwent etiological evaluation were not even adequately treated. Long-term follow up improved anemia treatment, and patients with improved anemia had better survival. In conclusion, we recommend an optimal evaluation of CKD patients with anemia and initiating treatment as early as possible.