Association Between Elevated Blood Eosinophils and Chronic Kidney Disease Progression: Analyses of a Large United States Electronic Health Records Database

Danuta Kielar,1 Andrew M Jones,2 Xia Wang,3 Heide Stirnadel-Farrant,1 Rohit K Katial,4 Abhinav Bansal,5 Manu Garg,5 Chandrakant Sharma,5 Shubhankar Thakar,5 Qin Ye5 1BioPharmaceuticals Medical, AstraZeneca, Cambridge, UK; 2Late-Stage Development, Respiratory & Immunology, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, USA; 3Data Science & AI, BioPharmaceuticals R&D, AstraZeneca, Gaithersburg, MD, USA; 4BioPharmaceuticals Medical, AstraZeneca, Gaithersburg, MD, USA; 5ZS, Philadelphia, PA, USACorrespondence: Danuta Kielar, AstraZeneca, Academy House, 136 Hills Road, Cambridge, CB2 8PA, UK, Tel +44 7384905053, Email danuta.kielar@astrazeneca.comBackground: Blood eosinophils can increase in response to infection, inflammation, and hypersensitivity reactions, yet their involvement in the progression of chronic kidney disease (CKD) is poorly understood. This study explores the relationship between blood eosinophils and CKD progression among patients in a real-world setting.Methods: This retrospective study analyzed data obtained from the Optum® de-identified electronic health records dataset in the United States. Patients diagnosed with CKD stage 3 or 4 (International Classification of Diseases diagnosis code or estimated glomerular filtration rate [eGFR] < 60 mL/min) between January 2011 and March 2018 were included and followed until progression to the next CKD stage, death, or dropout. The primary objective of this study was to assess the relationship between blood eosinophil counts (bEOS) and CKD progression, adjusting for clinical and demographic features as well as known risk factors for CKD stages 3– 4. The primary outcomes were CKD progression and all-cause mortality.Results: We found that high eosinophilic levels (bEOS ≥ 300 cells/μL) were associated with CKD progression from stage 3 to stages 4 or 5 (hazard ratio [HR] ranging from 1.30 to 1.50) and from stages 4 to 5 (HR ranging from 1.28 to 1.50). Among patients with CKD progres