Effect of vitamin K2 on progression of atherosclerosis and vascular calcification in non-dialyzed patients with chronic kidney disease stage 35 (Kurnatowska I, et al)
Atherosclerosis and vascular calcification are common complications of chronic kidney disease (CKD) and significant risk factors for cardiovascular incidence and mortality. Additionally, a high prevalence of suboptimal levels of vitamin K in patients with CKD stage 3 to 5 was found. With observational studies showing that high dietary vitamin K2 intake is associated with reduced risk of coronary vascular disease and vascular calcification, researchers sought to examine the effects of Vitamin K2 supplementation with a low-dose vitamin D, as well as the effect of vitamin D alone. The promising results have been published in the Polish Archives of Internal Medicine.
Researchers at the Medical University of Lodz (Poland), in conjunction with VitaK (Maastricht University, The Netherlands) and the International Science and Health Foundation (Poland), conducted this prospective randomized intervention study and assessed the impact of 90 mcg of vitamin K2 as MK-7 supplementation, vitamin D and K2 supplementation, and vitamin D supplementation alone (through 270 days) on the progression of atherosclerosis and calcification markers in non-dialyzed 3 to 5 stage CKD patients.
The following measurements were taken at baseline and after 270±12 days of supplementation 90 mcg vitamin K2 (menaquinone, MK-7) with 10 mcg cholecalciferol (K+D group) or 10 mcg cholecalciferol (group D) in 42 nondialyzed CKD patients: Common Carotid Intima Media Thickness (CCAIMT), Coronary Artery Calcification Score (CACS), serum mineral parameters, lipids, as well as the calcification modulators: matrix Gla protein (MGP), desphosphorylateduncarboxylated MGP (dpucMGP), osteoprotegerin (OPG), fetuin A, osteocalcin (OC) and fibroblast grown factor 23 (FGF23).
The progression of CACS in patients who received vitamin K2 was less than in the control group; however, the change was relatively small and only borderline significant probably due to too short observation period, low dose of vitamin K2, small group of patients and a wide range of coronary artery calcification (CAC) at baseline that is typical for patients with CKD. Furthermore, in this study the regression and stabilization of CACS was noticed in a few patients supplemented with MK-7, such effect was not observed in control group (vitamin D only group).
Vitamin K2 significantly changed the pattern of promoters and calcification inhibitors undercarboxylated/inactive matrix Gla protein (MGP), osteocalcin (OC), and osteoprotegerin (OPG), but failed to affect the progression of coronary artery calcification in CKD patients over the treatment period.
This study showed that the supplementation with vitamin K2 slowed significantly the progression of Common Carotid Intima Media Thickness, a good indicator of atherosclerosis and a powerful and well-established predictor of cardiovascular episodes and death in general and in CKD population.
The protective effect of vitamin K2 on progression of vessels damage would be associated with concomitant changes in the serum levels of calcification inhibitors like vitamin K-dependent proteins: osteocalcin (OC) and matrix GLA protein (MGP).
The researchers concluded that a 270-day course of 90 mcg of vitamin K2 as MK-7 administration may reduce the progression of atherosclerosis. Vitamin K2 significantly changed the pattern of promoters and calcification inhibitors inactive MGP, OC and OPG, but failed to affect the progression of coronary artery calcification in CKD patients over the treatment period.
In conclusion, vitamin K2 supplementation reduces the progression of atherosclerosis and might attenuate progression of vascular calcification in non-dialysis subjects in 3 to 5 stages of CKD. The mechanisms by which vitamin K2 may exert the protective effect on progression of vessels damage are still uncertain, but may be connected with the impact of MK-7 on calcification’s regulators, including the impact on the MGP carboxylation process.
Kurnatowska I, Grzelak P, Masajtis Zagajewska A, Kaczmarska M, Stefańczyk L, Vermeer C, Maresz K, Nowicki M. Effect of vitamin K2 on progression of atherosclerosis and vascular calcification in nondialyzed patients with chronic kidney disease stage 35. Pol Arch Med Wewn. 2015 Jul 15. pii: AOP_15_066. [Epub ahead of print]