The objective of this report was to systematically review the available evidence on the association of a positive factor V Leiden (FVL) or prothrombin gene (PG) test with a first, unprovoked venous thromboembolism (VTE) (suspected thrombophilia), and the risks and benefits resulting from test use. The report focused on patients presenting with a first episode of unprovoked VTE. The cost implications of FVL and PG testing in Canada were also assessed. The following research questions were addressed:

1. What is the clinical validity of factor V Leiden and prothrombin mutation tests in patients presenting with a first episode of unprovoked (i.e., idiopathic) VTE?
2. What is the clinical utility of testing for factor V Leiden and prothrombin mutations compared to no testing of patients presenting with a first episode of unprovoked (i.e., idiopathic) VTE?
3. What is the cost-effectiveness of testing for factor V Leiden and prothrombin mutation compared to no testing of patients presenting with a first episode of unprovoked (i.e., idiopathic) VTE?

Contents

• ACRONYMS AND ABBREVIATIONS
• EXECUTIVE SUMMARY
• 1. INTRODUCTION
• 2. ISSUE
• 3. OBJECTIVES
• 4. CLINICAL REVIEW
  • 4.1 Methods
  • 4.2 Results
• 5. PRIMARY ECONOMIC EVALUATION
  • 5.1 Background
  • 5.2 Methods
  • 5.3 Results
• 6. DISCUSSION
  • 6.1 Summary of Findings From the Systematic Review
  • 6.2 Summary of Findings From the Cost Analysis
• 7. CONCLUSIONS
• REFERENCES
• APPENDIX 1 LITERATURE SEARCH STRATEGY
• APPENDIX 2 DATA EXTRACTION FORM FOR ACCURACY AND CLINICAL EFFECTIVENESS REVIEW
• APPENDIX 3 INCLUDED AND EXCLUDED STUDIES FOR CLINICAL REVIEW
• APPENDIX 4 SELECTION OF INCLUDED STUDIES
• APPENDIX 5 CLINICAL STUDY CHARACTERISTICS
• APPENDIX 6 PATIENT CHARACTERISTICS
• APPENDIX 7 SUMMARY OF CRITICAL APPRAISAL OF INCLUDED STUDIES
• APPENDIX 8 SUMMARY OF CRITICAL APPRAISAL OF INCLUDED GUIDELINES
• APPENDIX 9 SUMMARY OF EXCLUDED ECONOMIC STUDIES

Suggested citation:

Canadian Agency for Drugs and Technologies in Health. Effectiveness of factor V Leiden and prothrombin mutation testing in patients presenting with a first unprovoked venous thromboembolic episode: a systematic review and economic analysis [Internet]. Ottawa: The Agency; 2015 Mar. (CADTH Optimal Use Report vol.4, no.1a). [cited yyyy mmm dd]. Available from: http://www.cadth.ca/media/pdf/OP0517_Thrombophilia_Science_Report.pdf

This report is prepared by the Canadian Agency for Drugs and Technologies in Health (CADTH). This report contains a comprehensive review of existing public literature, studies, materials, and other information and documentation (collectively the “source documentation”) available to CADTH at the time it was prepared, and it was guided by expert input and advice throughout its preparation.

The information in this report is intended to help health care decision-makers, patients, health care professionals, health systems leaders, and policy-makers make well-informed decisions and thereby improve the quality of health care services. The information in this report should not be used as a substitute for the application of clinical judgment in respect to the care of a particular patient or other professional judgment in any decision-making process, nor is it intended to replace professional medical advice. While CADTH has taken care in the preparation of this report to ensure that its contents are accurate, complete, and up-to-date, CADTH does not make any guarantee to that effect. CADTH is not responsible for any errors or omissions or injury, loss, or damage arising from or as a result of the use (or misuse) of any information contained in or implied by the information in this report.

CADTH takes sole responsibility for the final form and content of this report. The statements, conclusions, and views expressed herein do not necessarily represent the view of Health Canada or any provincial or territorial government.

Production of this report is made possible through a financial contribution from Health Canada.