Vitamin D binding protein and the need for vitamin D in hemodialysis patients

J Ren Nutr. 2008 Sep;18(5):400-7. doi: 10.1053/j.jrn.2008.04.013.


Objective: Vitamin D binding protein (DBP) is a polymorphic serum protein with a predominant role in a spectrum of biological activities. Chronic renal failure is characterized by deficient vitamin D metabolism. The present study investigates the impact of DBP polymorphism on the need for vitamin D in hemodialysis patients.

Design: This was a retrospective study.

Setting: This study included hemodialysis patients from the Renal Unit of Ghent University Hospital (Ghent, Belgium) and the Algemeen Stedelijk Ziekenhuis Geraardsbergen Hospital (Geraardsbergen, Belgium).

Methods: One hundred and ninety-one hemodialysis patients and 211 healthy subjects were recruited from the hemodialysis database. The DBP phenotypes were determined by polyacrylamide gel electrophoresis. Serum DBP, parathyroid hormone, 25-hydroxyvitamin D(3), 1,25-dihydroxyvitamin D(3), calcium, albumin, and phosphate were measured. Information regarding the intake of vitamin D analogues was collected.

Results: The phenotypic distributions of DBP were in agreement with Hardy-Weinberg equilibrium. Comparing allele frequencies of the two groups, there was an increased proportion of the DBP 2 allele in hemodialysis patients (P < .05). The median serum DBP concentration was lowest in the DBP 2-2 group. The need for oral vitamin D differed significantly (P < .01) between DBP phenotypes, and was greatest in DBP 2-2.

Conclusions: The present study demonstrates an altered DBP allele frequency in hemodialysis patients, compared with the general population. More importantly, vitamin D intake differs depending on the DBP polymorphism, and is greatest for end-stage renal disease patients with a DBP 2-2 phenotype. Therefore, vitamin D treatment deserves more careful monitoring among DBP 2-2 patients with end-stage renal disease.

MeSH terms

  • Aged
  • Case-Control Studies
  • Electrophoresis, Polyacrylamide Gel
  • Female
  • Gene Frequency
  • Humans
  • Kidney Failure, Chronic / therapy
  • Male
  • Middle Aged
  • Nutritional Requirements*
  • Parathyroid Hormone / blood
  • Phenotype
  • Polymorphism, Genetic*
  • Renal Dialysis*
  • Retrospective Studies
  • Vitamin D / administration & dosage*
  • Vitamin D-Binding Protein / genetics*


  • Parathyroid Hormone
  • Vitamin D-Binding Protein
  • Vitamin D