Associations between anemia and FGF23 in the CKiD study

Area of Science:

• Pediatric Nephrology
• Endocrinology
• Mineral and Bone Metabolism

Background:

• Fibroblast growth factor 23 (FGF23) is a key hormone in mineral and bone disorders, particularly in chronic kidney disease (CKD).
• CKD-associated anemia and iron deficiency may stimulate FGF23 production, potentially impacting CKD progression and cardiovascular health.
• Understanding the relationship between anemia, iron status, and FGF23 is crucial for managing pediatric CKD patients.

Purpose of the Study:

• To investigate the association between anemia and/or iron deficiency and circulating FGF23 concentrations in pediatric patients with CKD.
• To determine if anemia or iron deficiency are independent predictors of elevated FGF23 levels in the Chronic Kidney Disease in Children (CKiD) cohort.

Main Methods:

• Cross-sectional analysis of 493 pediatric patients from the CKiD study.
• Measurements included hemoglobin, iron parameters, C-terminal (total) FGF23, and intact FGF23.
• Multivariable regression models were used to assess associations, adjusting for relevant covariables.

Main Results:

• Anemic pediatric CKD patients (21%) exhibited significantly higher total FGF23 concentrations compared to non-anemic patients.
• Anemia was independently associated with increased total FGF23 levels after adjusting for multiple factors.
• Iron deficiency was not significantly associated with higher total FGF23, and anemia was not associated with intact FGF23 levels.

Conclusions:

• Anemia in pediatric CKD is associated with elevated total FGF23, suggesting potential impacts on FGF23 production and cleavage.
• The findings highlight a complex interplay between anemia and FGF23 metabolism in children with CKD.
• Further research is needed to explore non-mineral factors influencing FGF23 in pediatric CKD.