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Mutations, Hormone Therapy (HRT) and Venous Thromboembolism

This study has been completed.
National Heart, Lung, and Blood Institute (NHLBI)
Information provided by:
University of Washington Identifier:
First received: May 25, 2000
Last updated: February 8, 2016
Last verified: July 2005
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).

Cardiovascular Diseases
Venous Thromboembolism

Study Type: Observational

Further study details as provided by University of Washington:

Study Start Date: September 1998
Estimated Study Completion Date: August 2003
Detailed Description:


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.


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.


Ages Eligible for Study:   30 Years to 89 Years   (Adult, Senior)
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   No
No eligibility criteria
  Contacts and Locations
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Please refer to this study by its identifier: NCT00005515

Sponsors and Collaborators
University of Washington
National Heart, Lung, and Blood Institute (NHLBI)
OverallOfficial: Bruce Psaty University of Washington
  More Information

Publications: Identifier: NCT00005515     History of Changes
Other Study ID Numbers: 5033  R01HL060739 
Study First Received: May 25, 2000
Last Updated: February 8, 2016
Health Authority: United States: Federal Government

Additional relevant MeSH terms:
Cardiovascular Diseases
Venous Thromboembolism
Embolism and Thrombosis
Vascular Diseases processed this record on October 21, 2016