K2 supplementation improves cardiovascular outcome in dialysis patients
A broad insight into ways of evaluating and optimizing vitamin K status among dialysis patients has been presented in a review paper published lately in Nephrology Dialysis Transplantation. Its authors believe that repletion of vascular vitamin K stores effectively slows the development of vascular calcifications and significantly improves cardiovascular outcome parameters.
Issues like validity and interpretation of the available tests to assess vitamin K status, the impact of different dosing regimens and the choice of vitamin K species have been discussed. Tabular summaries of numerous studies evaluating vitamin K intake, vitamin K status, the association between vitamin K status and cardiovascular outcome and dose-finding studies of vitamin K2 in high-risk populations, in particular in in chronic kidney disease (CKD) and haemodialysis patients have been included in the paper.
As an outcome of a thorough database search, the authors managed to summarize the results of a large number of randomized controlled trials (RCTs) that evaluated the potential beneficial effects of long-term vitamins K1 and K2 supplementation on cardiovascular disease, bone density and fracture risk, and insulin resistance. Several trials of vitamin K2 supplements have been initiated recently in prevalent or incident haemodialysis patients. Most use a specific form of vitamin K2 called MenaQ7 as supplement, generally with thrice weekly administration after dialysis to ascertain compliance. Surrogate markers for cardiovascular disease under study are coronary artery calcification score and arterial stiffness measures such as pulse wave velocity.
“Clinical trials with MenaQ7 that are ongoing in Singapore, Belgium, USA and Denmark show huge interest of vitamin K2 supplementation in kidney patients,” says Dr. Katarzyna Maresz, president of the International Science and Health Foundation. “This noteworthy paper clearly demonstrates the large potential of MenaQ7 supplementation as a means to secure improvement in cardiovascular outcome among CKD and dialysis patients who are prone to severe calcification.”
Caluwé R, Verbeke F, De Vriese AS (2018) Evaluation of vitamin K status and rationale for vitamin K supplementation in dialysis patients, Nephrology Dialysis Transplantation, gfy373, doi: 10.1093/ndt/gfy373