Vitamin K and mortality in patients with chronic kidney disease
Abstract
Cardiovascular diseases are the leading cause of death in people with chronic kidney disease (CKD), among other things because of calcification of blood vessels. Vitamin K deficiency in CKD associated with abnormal bone mineralization as well as ectopic mineralization. Long-term observation of patients in NHANES (the Third National Health and Nutrition Examination Survey) found that adequate intake of vitamin K was associated with overall lower mortality rate and lower mortality rate from cardiovascular diseases in CKD population. In the group of hemodialysis patients studies show significant sub-clinical (functional) deficiency of vitamin K. PIVKA-II (prothrombin induced by vitamin K absence-II) appear to be a good marker of vitamin K resources in this group of patients. Other proteins vitamin K-dependent eg. matrix Gla protein (MGP) are used to identify a deficit of this vitamin. In the general population, stzudies on the relationship between vitamin K (phylloquinone and menaquinone), and cardiovascular diseases are inconclusive. The authors suggest that high intake of vitamin K is correlated with the use of a healthy diet, and thus with lower cardiovascular risk. It has not diagnosed vitamin K deficiency in patients with impaired renal function, or treated with dialysis. Also not recommended supplementation of this vitamin. The results of recent studies that suggest a vitamin K take place role in the prevention of vascular calcifications in CKD, may — in the future come to the changing nutritional guidelines. However, studies need to be continued in order to establish a link between vitamin K intake and mortality in these patients.