TY - JOUR
T1 - Vitamin K intake and status are low in hemodialysis patients
AU - Cranenburg, Ellen C. M.
AU - Schurgers, Leon J.
AU - Uiterwijk, Herma H.
AU - Beulens, Joline W. J.
AU - Dalmeijer, Gerdien W.
AU - Westerhuis, Ralf
AU - Magdeleyns, Elke J.
AU - Herfs, Marjolein
AU - Vermeer, Cees
AU - Laverman, Gozewijn D.
PY - 2012/9
Y1 - 2012/9
N2 - Vitamin K is essential for the activity of gamma-carboxyglutamate (Gla)-proteins including matrix Gla28 protein and osteocalcin; an inhibitor of vascular calcification and a bone matrix protein, respectively. Insufficient vitamin K intake leads to the production of non-carboxylated, inactive proteins and this could contribute to the high risk of vascular calcification in hemodialysis patients. To help resolve this, we measured vitamin K-1 and K-2 intake (4-day food record), and the vitamin K status in 40 hemodialysis patients. The intake was low in these patients (median 140 mu g/day), especially on days of dialysis and the weekend as compared to intakes reported in a reference population of healthy adults (mean K1 and K-2 intake 200 mu g/day and 31 mu g/day, respectively). Non-carboxylated bone and coagulation proteins were found to be elevated in 33 hemodialysis patients, indicating subclinical hepatic vitamin K deficiency. Additionally, very high non-carboxylated matrix Gla28 protein levels, endemic to all patients, suggest vascular vitamin K deficiency. Thus, compared to healthy individuals, hemodialysis patients have a poor overall vitamin K status due to low intake. A randomized controlled trial is needed to test whether vitamin K supplementation reduces the risk of arterial calcification and mortality in hemodialysis patients.
AB - Vitamin K is essential for the activity of gamma-carboxyglutamate (Gla)-proteins including matrix Gla28 protein and osteocalcin; an inhibitor of vascular calcification and a bone matrix protein, respectively. Insufficient vitamin K intake leads to the production of non-carboxylated, inactive proteins and this could contribute to the high risk of vascular calcification in hemodialysis patients. To help resolve this, we measured vitamin K-1 and K-2 intake (4-day food record), and the vitamin K status in 40 hemodialysis patients. The intake was low in these patients (median 140 mu g/day), especially on days of dialysis and the weekend as compared to intakes reported in a reference population of healthy adults (mean K1 and K-2 intake 200 mu g/day and 31 mu g/day, respectively). Non-carboxylated bone and coagulation proteins were found to be elevated in 33 hemodialysis patients, indicating subclinical hepatic vitamin K deficiency. Additionally, very high non-carboxylated matrix Gla28 protein levels, endemic to all patients, suggest vascular vitamin K deficiency. Thus, compared to healthy individuals, hemodialysis patients have a poor overall vitamin K status due to low intake. A randomized controlled trial is needed to test whether vitamin K supplementation reduces the risk of arterial calcification and mortality in hemodialysis patients.
KW - hemodialysis hazard
KW - mineral metabolism
KW - nutrition
KW - target organ damage
KW - vascular calcification
U2 - 10.1038/ki.2012.191
DO - 10.1038/ki.2012.191
M3 - Article
C2 - 22648294
SN - 0085-2538
VL - 82
SP - 605
EP - 610
JO - Kidney International
JF - Kidney International
IS - 5
ER -