Evaluation of vitamin B6 supplementation in Wilson's disease patients treated with D-penicillamine

BMJ Open Gastroenterol. 2023 Aug;10(1):e001211. doi: 10.1136/bmjgast-2023-001211.

Abstract

Introduction: Wilson's disease (WD) is a copper metabolism disorder characterised by a progressive accumulation of this metal mainly in the liver and the brain. Treatment is based on the removal of copper operated by the chelators, among which, D-penicillamine (DP) is prescribed as a first-line treatment in most situations. There is some evidence in linking the use of DP with a risk of vitamin B6; therefore, vitamin supplementation is sometimes recommended, although non-consensually. The objective of our study was to evaluate the level of vitamin B6 in WD patients treated with DP with and without associated supplementation.

Methodology: All WD patients followed at the National Reference Centre for WD in Lyon between January 2019 and December 2020 treated with DP for more than 1 year were included and separated in two groups according to vitamin B6 supplementation. The level of vitamin B6 was measured by the determination of pyridoxal phosphate (PLP).

Results: A total of 37 patients were included. Average age of 23.3±14.8 years, 15 patients with <18 years. Median duration of treatment was 51 (55.8) months. 15 patients were under vitamin B6 supplementation and 22 had interrupted it for more than 1 year. The median PLP level was significantly higher in the group with supplementation, 137.2 (86.7) nmol/L vs 64.9 (30.8) nmol/(p<0.01). No patient had a PLP level<35 nmol/L.

Conclusion: Long-term stable WD patients under DP treatment probably do not need vitamin B6 supplementation.

Keywords: Wilson's disease; inherited metabolic disease; vitamins.

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Copper / therapeutic use
  • Dietary Supplements
  • Hepatolenticular Degeneration* / drug therapy
  • Humans
  • Penicillamine / therapeutic use
  • Vitamin B 6* / therapeutic use
  • Vitamins
  • Young Adult

Substances

  • Vitamin B 6
  • Penicillamine
  • Copper
  • Vitamins