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Vitamin K Supplementation in Patients on Hemodialysis

Vitamin K Supplementation to Improve INR Stability in Patients on Hemodialysis Taking Warfarin for Atrial Fibrillation

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02324686
Acronym
VISTA
Enrollment
3
Registered
2014-12-24
Start date
2014-01-31
Completion date
2017-12-18
Last updated
2018-02-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

End Stage Renal Failure on Dialysis, Atrial Fibrillation

Keywords

Warfarin, International Normalized Ratio, Vitamin K

Brief summary

The purpose of this study is to determine whether vitamin K supplementation will improve anticoagulation control in patients on hemodialysis taking warfarin for atrial fibrillation. Patients who participate will receive vitamin K1 three times a week on dialysis days for a period of four months. INR levels collected during this period will be compared to the four month period prior to receiving the vitamin K1 to determine if vitamin K improves the standard deviation of INRs and time in therapeutic range.

Detailed description

Patients on hemodialysis with atrial fibrillation are at increased risk of stroke. These patients often take warfarin to reduce this risk. Warfarin is a drug that is used to prevent clots in the bloodstream. The dose of warfarin varies from person to person, and its effect is measured using a blood test called the international normalized ratio (INR). In most patients with atrial fibrillation the goal is to keep the INR between 2 and 3. Patients on hemodialysis often have unstable INR levels. Vitamin K supplementation has been shown to improve INR control in patients on warfarin but has not yet been studied in hemodialysis patients. In this study, patients on hemodialysis receiving warfarin for atrial fibrillation will receive vitamin K 400 mcg orally three times a week on dialysis days for 4 months. INR levels in the four months before and the four months while receiving vitamin K will be reviewed. The primary end point will look at INR stability and be measured by calculating the standard deviation of INR values before and after receiving vitamin K. The goal of this study is to determine whether vitamin K supplementation improves INR control in patients on hemodialysis taking warfarin for atrial fibrillation.

Interventions

Vitamin K1 400 mcg orally three times a week on dialysis days for four months

Sponsors

University Health Network, Toronto
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* greater than 18 years of age * Receiving in-house hemodialysis for at least 6 months * Previously diagnosed with atrial fibrillation * On warfarin for at least 6 months with a target INR of 2-3

Exclusion criteria

* are unable to provide informed consent * have a mechanical heart valve * are receiving supplements containing vitamin K * have a known hypersensitivity to vitamin K

Design outcomes

Primary

MeasureTime frameDescription
INR stability (standard deviation of INR values)4 months before and 4 months after interventionstandard deviation of INR values, 4 months before and 4 months after the intervention

Secondary

MeasureTime frameDescription
Adverse events4 months before and 4 months after interventionNumber and types of thromboembolic and bleeding complications, 4 months before and 4 months after the intervention
Time in Therapeutic Range (Percentage of time INR levels within range)4 months before and 4 months after intervention, 4 months before and 4 months after the intervention

Countries

Canada

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026