Effect of vitamin K2 supplementation on functional vitamin K deficiency in hemodialysis patients: a randomized trial

Westenfeld R, Krueger T, Schlieper G, et al. · American Journal of Kidney Diseases

The clearest dose-response in the carboxylation marker: inactive matrix Gla protein fell in a dose- and time-dependent way, with response rates of 77% at 135 ug/day and 93% at 360 ug/day, from a baseline 4.5-fold above healthy controls. It is also the study that established how widespread functional vitamin K deficiency is in dialysis.

Population

Long-term haemodialysis patients, with 50 healthy age-matched controls, 6 weeks

Intervention

MK-7 at 45, 135 or 360 ug/day

Comparator

Three parallel dose groups (no placebo)

Limitations

53 patients, no placebo arm, 6 weeks; biomarker endpoints only; a dialysis population whose vitamin K status is far worse than the general public's.