Vitamin K supplementation to decrease variability of International Normalized Ratio in patients on vitamin K antagonists: a literature review

Abstract

Vitamin K supplementation may decrease variability of INRs in patients with a history of unstable INRs. Further studies are needed in larger populations to clarify the true effects of vitamin K supplementation.

Prediction of Warfarin Dose: Why, When and How?

“…Studies on combining warfarin treatment with a vitamin K supplement have been performed with the aim to reduce the variability in drug response caused by a low or sporadic dietary intake [20]. These studies show varying results, but the overall conclusion is that vitamin K supplements do decrease the variation in drug response caused by dietary intake.…”

The use of vitamin K supplementation to achieve INR stability: A systematic review and meta-analysis

“…Most research has focused on controlling INR fluctuations by modifying dietary vitamin K (Holmes, Hunt, & Shearer, 2012;Kim et al, 2010). This is the first systematic review addressing use of vitamin K supplementation to achieve INR stability in anticoagulant therapy and updates an earlier literature review (Ford & Moll, 2008) by inclusion of a more recent clinical trial and use of meta-analytic methods. Primary care providers, cardiologists, neurologists, hematologists, and NPs all care for patients on VKA therapy, which makes this systematic review clinically relevant.…”

Anticoagulation Control with Daily Low‐Dose Vitamin K to Reduce Clinically Adverse Outcomes and International Normalized Ratio Variability: A Systematic Review and Meta‐Analysis

“…Indeed, differences in the risk of major bleeding and thromboembolic events between patients receiving daily vitamin K supplementation and placebo were nonsignificant. Our findings reinforce previous findings, with the caveat that our study had a more systematic approach in estimating treatment effects associated with vitamin K use and quality of included trials using the GRADE system …”

“…5,6 Previous observational studies and randomized controlled trials (RCTs) have evaluated lower doses of oral vitamin K or purposeful manipulation of dietary vitamin K intake to improve INR control. [7][8][9][10][11][12][13] However, to our knowledge, no structured systematic review has yet addressed the impact of vitamin K supplementation on both important clinical outcomes and INR control related to VKA therapy.…”