Low-dose vitamin K to augment anticoagulation control

Area of Science:

• Pharmacology
• Hematology
• Clinical Medicine

Background:

• Warfarin therapy requires careful monitoring of International Normalized Ratios (INRs) to prevent bleeding or clotting.
• Fluctuating INRs in patients on warfarin can be challenging to manage, even without identifiable causes.
• Vitamin K plays a crucial role in the coagulation cascade and warfarin metabolism.

Purpose of the Study:

• To evaluate the efficacy of daily low-dose oral vitamin K supplementation in reducing INR variability.
• To assess the impact of vitamin K on maintaining INRs within the therapeutic range for warfarin patients.

Main Methods:

• Retrospective analysis of INR data from patients on warfarin with fluctuating INRs.
• Inclusion of eight patients receiving daily oral vitamin K supplementation (starting at 100 microg/day).
• Monitoring of INR responses by anticoagulation providers.

Main Results:

• Daily vitamin K supplementation significantly decreased INR standard deviation (p<0.05).
• The percentage of INRs within 0.2 units of the target range increased from 32% to 57% (76% relative increase).
• Time in therapeutic INR range also showed a significant improvement.

Conclusions:

• Low-dose oral vitamin K supplementation effectively reduced INR fluctuations in selected warfarin patients.
• Vitamin K therapy improved the stability and time in therapeutic range of INRs.
• This intervention offers a potential strategy for managing difficult-to-control INRs in warfarin therapy.