Vitamin K2 supplementation in haemodialysis patients: a randomized dose-finding study.
- 2013-11-26
- Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association 29(7)
- Rogier Caluwé
- Stefaan Vandecasteele
- Bruno Van Vlem
- Cees Vermeer
- An S De Vriese
- PubMed: 24285428
- DOI: 10.1093/ndt/gft464
Study Design
- Type
- Randomized Controlled Trial (RCT)
- Population
- 200 chronic haemodialysis patients
- Methods
- randomly receive 360, 720 or 1080 µg of MK-7 thrice weekly for 8 weeks
- Duration
- 8 weeks
Background
Haemodialysis patients suffer from accelerated vascular calcification. The vitamin K-dependent matrix Gla protein (MGP) is one of the most powerful inhibitors of vascular calcification. Haemodialysis patients have high levels of the inactive form of MGP (desphosphorylated-uncarboxylated-MGP, dp-uc-MGP) and may benefit from pharmacological doses of vitamin K2 (menaquinone) to improve the calcification inhibitory activity of MGP.Methods
To determine the optimal dose of menaquinone-7 (MK-7) for MGP activation, 200 chronic haemodialysis patients were recruited to randomly receive 360, 720 or 1080 µg of MK-7 thrice weekly for 8 weeks. Dp-uc-MGP was measured at baseline and after 8 weeks. Dietary intake of vitamin K1 (phylloquinone) and menaquinone was estimated based on a detailed questionnaire.Results
At baseline, dp-uc-MGP was not associated with phylloquinone intake (P = 0.92), but correlated inversely with menaquinone intake (P = 0.023). MK-7 supplementation dose dependently reduced dp-uc-MGP. The levels decreased by 17, 33 and 46% in the respective groups. Drop-outs were mainly due to gastrointestinal side-effects related to the unpleasant smell of the tablets.Conclusions
Chronic haemodialysis patients have high levels of inactive MGP, possibly related to a low dietary vitamin K intake. Pharmacological doses of MK-7 dose-dependently reduce dp-uc-MGP. Menaquinone supplementation may be a novel approach to prevent vascular calcifications in chronic haemodialysis patients.Research Insights
At baseline, dp-uc-MGP was not associated with phylloquinone intake (P = 0.92)
- Effect
- Neutral
- Effect size
- Small