The relationship between FGF23 and body composition according to albuminuria stage in type 1 diabetes.

AIMS:Fibroblast growth factor 23 (FGF23) and obesity are linked to kidney disease. However, the relationship between FGF23 and body composition is unclear. Associations between FGF23 and body composition were investigated in type 1 diabetes from the Finnish Diabetic Nephropathy Study according to albuminuria stages. METHODS:Data were available from 306 adults with type 1 diabetes (229 normal albumin excretion rate, T1Dnormo; 38 microalbuminuria, T1Dmicro; 39 macroalbuminuria, T1Dmacro), and 36 controls. Serum FGF23 was measured by ELISA. Body composition was assessed with dual-energy X-ray absorptiometry. Associations between body composition and serum FGF23 were investigated using linear regression models. RESULTS:Compared with T1Dnormo, individuals with more advanced kidney disease were older, had longer diabetes duration, higher serum hsCRP, and higher FGF23 concentration. However, FGF23 concentration was comparable between T1Dnormo and controls. Adjusted for potential confounders, in T1Dmicro, FGF23 was positively associated with the percentages of total fat, visceral fat, and android fat tissues, while negative associations between FGF23 and lean tissue were observed. FGF23 was not associated with body composition in T1Dnormo, T1Dmacro, and controls. CONCLUSIONS:In type 1 diabetes, the relationship between FGF23 and body composition is dependent on albuminuria stages.