This study is a monocentric, 1-armed interventional trial. Participants will be recruited at the University Hospital of the RWTH Aachen.~We will analyse serially collected serum from 10 dialysis patients, after ingestion of a single vitamin K supplement, compared to healthy controls. Lipoprotein fractions will be isolated and the corresponding vitamin K contents will be measured by chromatography.~The vitamin K supplement contains 3 subforms of vitamin K: vitamin K1 (1000µg), menaquinone-4 (1000µg) and menaquinone-7 (200µg).
Chronic kidney disease (CKD) patients have an increased cardiovascular risk with corresponding cardiovascular calcifications. CKD patients exhibit a functional vitamin K deficiency. Calcification can be prevented by vitamin K intake. The aim of this study is to investigate the cause for the vitamin K deficiency beyond a diminished dietary vitamin K uptake.