Abstract: FR-PO266

Bone Content Is Related with Serum Fibroblast Growth Factor-23 (FGF23) in Patients on Maintenance Hemodialysis (MHD)

Session Information

Category: Mineral Disease

  • 1202 Mineral Disease: Vitamin D, PTH, FGF-23

Authors

  • Hasuike, Yukiko, Internal Medicine, Div Kidney and Dialysis, Nishinomiya, 兵庫県, Japan
  • Fukao, Wataru, Internal Medicine, Div Kidney and Dialysis, Nishinomiya, 兵庫県, Japan
  • Morikami, Yuki, Internal Medicine, Div Kidney and Dialysis, Nishinomiya, 兵庫県, Japan
  • Kimura, Tomoko, Internal Medicine, Div Kidney and Dialysis, Nishinomiya, 兵庫県, Japan
  • Nagasawa, Yasuyuki, Internal Medicine, Div Kidney and Dialysis, Nishinomiya, 兵庫県, Japan
  • Nakanishi, Takeshi, Internal Medicine, Div Kidney and Dialysis, Nishinomiya, 兵庫県, Japan
Background

FGF23 is a circulating factor that plays an critical role in the regulation of phosphate and vitamin D. In MHD patients, an increase in FGF23 can lead to the development of cardiovascular complications. FGF23 is produced by mature osteoblasts and osteocytes, however, the relationship between bone and FGF23 production remains poorly understood. We investigated whether bone content is related with FGF23 levels in MHD patients.

Methods

MHD patients with dialysis vintage at least 3 months (n=107) were enrolled in this study. Serum concentration of intact FGF23 (ELISA, Kainos) and the factors related to mineral bone disorders (calcium, phosphorus, bone-type ALP [BAP], 1,25(OH)2vitamin D [calcitriol], 25(OH)vitamin D), inflammation (high-sensitivity CRP, interleukin-6, tumor necrosis factor-α), uremia (creatinine, p-crezol, indoxyl-sulfate, pentosidine) were measured. Walking speed, anthropometric parameters (body mass index, grip strength), bioelectrical impedance analysis (fat mass, body water volume) using inBody, and advanced body composition parameters (bone mineral content [BMC], bone mineral density [BMD], muscle mass) using Hologic QDR Discovery were assessed. The association between these factors and FGF23 were investigated.

Results

MHD patients recruited in this study showed mean age of 66.1±1.1 years, mean dialysis vintage 88.3±8.5 months, and median of serum FGF23 of 2100 (541 to 5825 pg/ml). Log-transformed FGF23 levels were associated with body weight, muscle mass, BMC, BMD, grip strength, serum calcium, phosphates, creatinine, and negatively linked with age, BAP, and walking speed. The stepwise regression analyses revealed that serum phosphorus, calcium, and BMC were the independent predictors of FGF23 (standardized regression coefficients were 0.620, 0.442, and 0.381, respectively, R2=0.762, p<0.0001). There was no significant relationship between FGF23 and serum calcitriol.

Conclusion

FGF23 production can be independently associated with BMC as well as calcium and phosphate in MHD patients.