Contact information
Type
Scientific
Primary contact
Dr F.J.M. van der Meer
ORCID ID
Contact details
Leiden University Medical Center
Department of Hematology
P.O. Box 9600
Leiden
2300 RC
Netherlands
+31 (0)71 5263901
f.j.m.van_der_meer@lumc.nl
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
Project 2005.2; NTR314
Study information
Scientific title
Acronym
Study hypothesis
1. Oral anticoagulant control is less stable at a low average intake of vitamin K
2. As a consequence, a low dose vitamin K supplement results in a more stable anticoagulant effect in patients using vitamin K antagonists (VKA)
3. Dietary intake of vitamin K is associated with sensitivity to VKA and stability of anticoagulant treatment
4. Polymorphisms of the VKORC1 gene are associated with sensitivity to VKA and stability of anticoagulant treatment
Ethics approval
Ethics approval received from the local medical ethics committee
Study design
Randomised, double-blinded, placebo controlled parallel group trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
Hospitals
Trial type
Treatment
Patient information sheet
Condition
Thrombosis, emboly, anticoagulant treatment
Intervention
1. Treatment group: 100 microgram vitamin K for 24 weeks
2. Placebo group: placebo for 24 weeks
Intervention type
Supplement
Phase
Not Specified
Drug names
Vitamin K
Primary outcome measures
1. Quality of anticoagulant treatment
2. Expressed as time in therapeutic range
Secondary outcome measures
1. Number of international normalised ratios (INRs) in therapeutic range
2. Bleeding and thromboembolic complications
Overall trial start date
16/11/2004
Overall trial end date
01/06/2006
Reason abandoned
Eligibility
Participant inclusion criteria
1. Patients treated at the Leiden anticoagulation clinic with an indication for long-term oral anticoagulant therapy using the vitamin K antagonist phenprocoumon
2. Age between 18 and 80 years
3. Informed consent
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
200
Participant exclusion criteria
1. Treatment by a medical specialist for liver failure
2. Haemo or peritoneal dialysis
3. Pregnancy or a planned pregnancy, puerperium
4. Any chronic condition with an expected median survival of less than 6 months
an expected interruption of oral anticoagulant treatment of more than 1 week
5. Self-management of oral anticoagulant therapy
6. Other drugs affecting haemostasis (aspirin, heparin, clopidogrel)
Recruitment start date
16/11/2004
Recruitment end date
01/06/2006
Locations
Countries of recruitment
Netherlands
Trial participating centre
Leiden University Medical Center
Leiden
2300 RC
Netherlands
Sponsor information
Organisation
Leiden University Medical Center (LUMC) (The Netherlands)
Sponsor details
Department of Hematology
P.O. Box 9600
Leiden
2300 RC
Netherlands
Sponsor type
Charity
Website
Funders
Funder type
Charity
Funder name
Dutch Thrombosis Foundation (Trombosestichting Nederland) (The Netherlands)
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Results - basic reporting
Publication summary