Anemia and estimated glomerular filtration rates

Area of Science:

• Nephrology
• Hematology
• Epidemiology

Background:

• Anemia is common in chronic kidney disease.
• The relationship between estimated glomerular filtration rate (eGFR) and anemia prevalence is not fully understood, particularly at higher eGFR levels.
• Current reporting practices for eGFR may not fully capture the risk of anemia.

Purpose of the Study:

• To investigate the association between eGFR and anemia prevalence in adults aged 50 years and older.
• To assess the implications of this relationship for reporting eGFR values.

Main Methods:

• Retrospective review of serum creatinine and hemoglobin results from 18,474 outpatients.
• Calculation of eGFR using CKD-EPI and MDRD equations.
• Statistical analysis to determine the odds of anemia (WHO definition) across different eGFR strata, adjusted for age and gender.

Main Results:

• A U-shaped relationship was observed between eGFR and anemia prevalence.
• The lowest anemia proportion occurred at eGFRs of 80-99 mL/min/1.73 m².
• Anemia prevalence increased significantly at eGFRs of 60-69 mL/min/1.73 m² and 100-109 mL/min/1.73 m², indicating a dose-response effect.

Conclusions:

• The study identified a U-shaped association between anemia and eGFR.
• Reporting eGFR values greater than 60 mL/min/1.73 m² is suggested.
• Further research is needed to confirm these findings and evaluate the clinical utility and potential risks of reporting higher eGFR values.