Mutations, Hormone Therapy (HRT) and Venous Thromboembolism
- Conditions
- Cardiovascular DiseasesVenous ThromboembolismPostmenopause
- Registration Number
- NCT00005515
- Lead Sponsor
- University of Washington
- Brief Summary
To assess the interaction between hormone replacement therapy and the prothrombotic mutations, Factor V Leiden and the recently described prothrombin mutation (20210A) on the incidence of venous thromboembolism (VTE) in a population-based case-control study conducted at Group Health Cooperative of Puget Sound (GHC).
- Detailed Description
BACKGROUND:
Epidemiologic studies have identified Factor V Leiden as the most common cause of heritable thrombophilia, a prothrombotic mutation associated with a 5 to 7-fold increase in the risk of venous thromboembolism (VTE). In pre-menopausal women, the use of oral contraceptives is associated with a 4-fold increase in VTE risk, and the joint effects of oral contraceptive use and Factor V Leiden carriership increase the VTE risk of by a factor of 35. Recently, the results of several observational studies and randomized clinical trials suggest that in post-menopausal women, the use of hormone replacement therapy is associated with a 3-fold increase in VTE risk. Whether post-menopausal women with prothrombotic mutations experience a similar 20-fold increase in risk when they take post-menopausal hormones remains unknown.
DESIGN NARRATIVE:
In this case-control study, post-menopausal women with a first episode of objectively confirmed venous thromboembolism, and population-based controls were identified and recruited from the GHC enrollment files. Controls were frequency matched to the cases on age and calendar-year. Data collection included a review of ambulatory medical record and a telephone interview. The GHC computerized pharmacy database was used to assess exposure to hormone replacement therapy. A venous blood specimen was obtained from consenting subjects, processed into aliquots of white cells, plasma, and red cells, and stored at 70 degrees C prior to laboratory analysis. DNA was extracted from white cells, and molecular genotyping assays were conducted to assess carriership of prothrombotic mutations.
Recruitment & Eligibility
- Status
- COMPLETED
- Sex
- Female
- Target Recruitment
- Not specified
Not provided
Not provided
Study & Design
- Study Type
- OBSERVATIONAL
- Study Design
- Not specified
- Primary Outcome Measures
Name Time Method
- Secondary Outcome Measures
Name Time Method