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The comparative effectiveness of warfarin and new oral anticoagulants for the extended treatment of venous thromboembolism
Investigator (PI): Fang, Margaret
Performing Organization (PO): (Current): University of California, San Francisco, School of Medicine, Department of Medicine, Division of Hospital Medicine / (415) 514-1780
Supporting Agency (SA): Patient-Centered Outcomes Research Institute (PCORI)
Initial Year: 2016
Final Year: 2022
Record Source/Award ID: PCORI/NOACs-1510-32651
Funding: Total Award Amount: $3,940,065
Award Type: Contract
Award Information: PCORI: More information and project results (when completed)
Abstract: Venous thromboembolism (VTE) causes more than half a million hospitalizations and more than 100,000 deaths each year in the United States. VTE is typically treated with at least three months of an anticoagulant, or blood-thinning, medication. Afterward, patients are often given the option to extend anticoagulant treatment for a longer period to prevent VTE recurrence. Remaining on anticoagulants, however, can lead to serious bleeding complications and can be expensive and inconvenient for patients. The anticoagulant treatment options for VTE treatment include warfarin and four newer oral anticoagulants (NOACs). At present, there is considerable uncertainty about which medication is the best choice for extended VTE treatment. Choosing the best anticoagulant strategy is particularly difficult when treating people of older age, people who have kidney disease, or people who have high bleeding risk, due to the scant evidence available on the relative benefits and harms in these populations. The long-term objective of our project is to compare the benefits and harms of different anticoagulant options for the extended treatment of VTE, information that will be critical in helping clinicians and patients personalize their treatment decisions. Our study focuses on people who have completed at least three months of anticoagulant treatment for VTE and compares the outcomes of 1) people who remain on anticoagulants with those who stop anticoagulants and 2) those who are treated with extended warfarin compared with NOAC treatment. We will also examine whether the benefits and harms of treatment differ by age, kidney function, or bleeding risk. Our study will be based in Kaiser Permanente Northern California and Kaiser Permanente Southern California--two large, integrated health care delivery systems that provide comprehensive medical care for more than 7.7 million patients in California. We will identify in these health systems all adults treated for VTE from years 2010 to 2015 and collect information from electronic health records on their health history, anticoagulant treatment choices, and clinical outcomes. Next, we will survey patients with VTE treated in more recent years (2014-2016) and measure their self-reported health, well-being, and satisfaction with treatment. The main outcome of the study is the net benefit of one treatment strategy compared with another, measured in terms of the number of VTE events prevented and the number of bleeding complications induced. Because our study is an observational study of actual clinical care, we will then apply advanced statistical techniques to maximize the validity of our results. Our proposed study offers several key strengths: we will be able to study a very large group of patients who represent people in real-world settings and can complete the project at a fraction of the cost and time required by randomized clinical trials.
MeSH Terms:
  • * Administration, Oral
  • Aged
  • Anticoagulants /*administration & dosage
  • California
  • Comparative Effectiveness Research
  • Decision Making
  • Delivery of Health Care
  • Electronic Health Records
  • Hemorrhage /drug therapy
  • Humans
  • Insurance, Health
  • Kidney Diseases /complications
  • Observational Studies as Topic
  • Outcome Assessment, Health Care
  • Patient Satisfaction
  • Recurrence
  • Risk
  • Self Report
  • Venous Thromboembolism /*drug therapy
  • Warfarin /*administration & dosage
Country: United States
State: California
Zip Code: 94143
UI: 20164142
Project Status: Ongoing
Record History: ('2017: Project extended to 2021.',) ('2018: Project extended to 2022.',)