Daily Vitamin K in Patients on Warfarin With Unstable INRs

January 11, 2010 updated by: University of North Carolina, Chapel Hill

Use of Daily Vitamin K Supplementation in Patients on Warfarin With a History of Frequent Dose Changes or Variable INRs

The purpose of this study is to determine if daily Vitamin K supplementation stabilizes INRs in patients taking warfarin with a history of frequent dose changes or variable INRs.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Consistent daily Vitamin K intake may contribute to the stabilization of INR values in patients with unstable INRs on warfarin therapy. Subjects with unstable INRs will be identified from the existing patient records of the UNC Anticoagulation Clinics. Eligible subjects will sign an informed consent form and will receive a point-of-care (POC) INR monitoring device. They will undergo 9 weeks of home INR monitoring via the POC device (with monthly clinic follow-up). They will subsequently be provided with 500 mcg Vitamin K tablets to be taken once daily. Weekly POC INR monitoring with monthly clinic follow-up will continue for an additional 8 weeks.

Study Type

Interventional

Enrollment (Actual)

15

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • North Carolina
      • Chapel Hill, North Carolina, United States, 27599
        • University of North Carolina at Chapel Hill

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Patient of UNC Anticoagulation Clinic with INR target of 2.0-3.0 and at least 9 months on uninterrupted warfarin
  • Unstable INRs for the past 6 months, defined as a minimum number of warfarin dose changes of 3
  • Patient demonstration of proper POC device technique on 2 measurements during one teaching session with investigator
  • Age greater than or equal to 18 years

Exclusion Criteria:

  • Stroke or TIA within the previous 12 months
  • VTE within the last 3 months
  • Antiphospholipid antibody syndrome
  • Pregnant patients, since warfarin is contraindicated during pregnancy

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Non-Randomized
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Number of warfarin adjustments required in each phase
Time in therapeutic, sub-, and supra-therapeutic range
Variance/SD of INRs for each patient
Adherence assessed by pill counts and pharmacy record review
Thrombotic/bleeding episodes

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

University of North Carolina, Chapel Hill

Investigators

  • Principal Investigator: Stephan Moll, M.D., University of North Carolina, Chapel Hill

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

October 1, 2005

Primary Completion (Actual)

May 1, 2006

Study Completion (Actual)

May 1, 2006

Study Registration Dates

First Submitted

February 3, 2006

First Submitted That Met QC Criteria

February 3, 2006

First Posted (Estimate)

February 6, 2006

Study Record Updates

Last Update Posted (Estimate)

January 12, 2010

Last Update Submitted That Met QC Criteria

January 11, 2010

Last Verified

January 1, 2010

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 05-MED-491

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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