Impact of Vitamin K supplementation on cardiovascular health outcomes associated with kidney disease – A systematic review and meta-analysis

Cardiovascular disease is the leading cause of morbidity and mortality among patients with chronic kidney disease (CKD) and end-stage kidney disease (ESKD). Vitamin K2, through its role in Vitamin K-dependent proteins, has been proposed to attenuate vascular calcification (VC) and arterial stiffness, yet deficiency is common in CKD. This systematic review and meta-analysis evaluated randomised controlled trials and cohort studies comparing Vitamin K2 supplementation with placebo or no treatment in CKD and ESKD patients. Outcomes included pulse wave velocity, coronary artery calcification, abdominal aortic calcification, and mortality. Eight eligible studies were included. Pooled analyses revealed no significant effect of Vitamin K2 on arterial stiffness, VC, or cardiovascular mortality, although a modest reduction in all-cause mortality was noted, largely driven by cohort data. While biochemical improvements such as reduced dp-ucMGP were observed, these did not consistently translate into clinical benefit. Overall, Vitamin K2 supplementation shows potential for improving vascular biomarkers but lacks strong evidence for reducing cardiovascular events or mortality. Larger, well-designed trials are needed to establish its clinical role in CKD populations.