부산대학교 도서관

Background. Cardiovascular calcifications are prevented by matrix Gla protein (MGP), a vitamin K-dependent protein. Haemodialysis patients exhibit marked vitamin K deficiency. The randomized, prospective, open-label, multicentre VitaVasK trial analysed whether vitamin Kl supplementation reduces progression of coronary artery calcifications (CACs) and thoracic aortic calcifications (TACs). Methods. Patients with pre-existing CACs were randomized to continue on standard care or to additionally receive 5 mg of vitamin Kl orally thrice weekly. Hierarchically ordered primary endpoints were progression of TAC and CAC in computed tomography scans at 18 months. Linear mixed effects models with repeated measures at baseline and 12 and 18 months assessed treatment effects after adjusting for study site. Results. Of 60 randomized patients, 20 dropped out for reasons unrelated to vitamin Kl, resulting in 23 control and 17 vitamin Kl patients. The trial was stopped early due to slow recruitment. At 18 months, the average TAC progression was 56% lower in the vitamin Kl compared with the control group (p = .039). CAC significantly progressed within the control group, but not within the vitamin Kl group. Average progression at 18 months was 68% lower in the vitamin Kl compared to the control group (P = .072). Vitamin Kl reduced plasma levels of pro-calcific uncarboxylated MGP by 69% at 18 months. No treatment-related adverse events were noted. Conclusion. Vitamin Kl intervention is a potent, safe and cost-effective approach to correct vitamin K deficiency and to potentially reduce cardiovascular calcification in this high-risk population. Patients on chronic dialysis exhibit extensive cardiovascular calcifications and vitamin K deficiency. The vitamin K-dependent matrix Gla protein (MGP) is a potent inhibitor of vascular calcification. The multicentre, randomized, open-label, controlled VitaVasK trial showed marked attenuation of cardiovascular calcification progression in chronic haemodialysis patients treated with vitamin Kl. Vitamin Kl supplementation greatly increased the serum vitamin K concentration and reduced inactive MGP levels. The treatment was safe, as no adverse advents were noted. Larger randomized controlled trials are needed to confirm vitamin Kl therapy as a safe, potent and cost-effective treatment option to reduce the progression of vascular calcification in haemodialysis patients. Keywords: matrix Gla protein, valvular calcification, vascular calcification, vitamin K
INTRODUCTION Patients on maintenance haemodialysis (HD) exhibit a greatly increased cardiovascular mortality associated with cardiovascular calcifications [1]. Cardiovascular calcifications result from a positive phosphate and calcium balance, as well as [...]