Use of Phytonadione to Reduce INR Variability in Patients on Long-term Warfarin Therapy
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 发起方
- 入组人数
- 370
- 试验地点
- 2
- 主要终点
- The primary outcome of this study is to determine the length of time in therapeutic INR range for patients given phytonadione and warfarin compared to warfarin alone
研究概览
简要总结
Background: Warfarin is used as an anti-coagulant in patients at risk of developing thrombosis. It has a narrow therapeutic index necessitating close monitoring of International Normalized Ratio (INR). According to a meta-analysis, patients were in therapeutic range only 63.6% of the time. This increases the risk of bleeding or thrombosis. Various retrospective and prospective studies have looked at supplementation with phytonadione in these patients to reduce the variability of INR showing an improvement in variability. Most of these studies have only been done in a small number of patients already on warfarin therapy. This study will focus on patients newly starting warfarin therapy.
Methods: This study is a prospective, randomized, controlled trial performed at James A. Haley Veterans' Hospital (JAHVA). Patients who meet criteria and sign informed consent will receive either phytonadione with warfarin or warfarin alone. Based on a power calculation for 80%, a total of 370 patients will be enrolled (185 participants in each arm). Participants will be randomized to either intervention or control. Intervention group participants will be prescribed their usual starting dose of warfarin along with 200 mcg phytonadione by mouth daily. Control group participants will be prescribed their usual starting dose of warfarin. Both groups will follow the usual standard of care. They will come in for a follow-up INR and warfarin dose titration at least once per week until therapeutic, and then as instructed up to every 6 weeks thereafter. Both groups will participate in anticoagulation clinic activities that constitute the current standard of care. Intervention will last for a total of 6 months for each participant once enrolled.
Hypothesis:Participants in the intervention group being supplemented with 200mcg of phytonadione will spend more total time with a therapeutic INR than participants in the control group.
详细描述
See above.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Be eighteen years of age and older
- •Have a long-term indication for warfarin (will need to be on warfarin for 6 months or longer)
- •Be a new patient on warfarin therapy, or a patient previously on warfarin therapy who has been taken off therapy for more than 2 weeks and needs to be titrated again
- •Anticipate receiving medical care at the study site for the duration of the study
- •Have transportation to and from the JAHVA
- •Have read and signed the Informed Consent document after the study has been fully explained and has had all questions answered
排除标准
- •Have liver or kidney failure
- •Are on hemodialysis or peritoneal dialysis
- •Are pregnant or planning to become pregnant
- •Have Alzheimer's disease, cognitive impairment, or visual impairment
- •Are not compliant with medications
- •Are participating in another study
- •Have scheduled surgery or are planning to undergo major surgery
- •Cannot be reached by telephone
- •Take over-the-counter vitamin K supplementation except multivitamins
结局指标
主要结局
The primary outcome of this study is to determine the length of time in therapeutic INR range for patients given phytonadione and warfarin compared to warfarin alone
时间窗: 6 months
次要结局
- Secondary outcomes include the number of adverse events in the form of bleeding or thrombosis for both groups.(6 months)
研究者
To-Nga Huynh, PharmD.
Anticoagulation Clinical Pharmacist
James A. Haley Veterans Administration Hospital