Construction and External Validation of a Predictive Clinico-biological Score of the Risk of Venous Thrombosis in Women Under Combined Oral Contraceptives

Study Overview
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Brief Summary
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the investigators hypothesize that some of these polymorphisms contribute to VTE risk in women using COC, and that their screening could to help assess individual risk of VTE before COC prescription. In order to test this hypothesis the investigators propose to build a predictive score for VTE in women using COC based on clinical and biological factors. To this end the investigators have a large case study (including 766 patients) recruited at the Centre d'Exploration des Pathologies Hémorragiques et Thrombotiques (CEHT) of the laboratory of Hematology (La Timone Hospital, Marseille) between 2003 and 2013. The cases had a personal history of documented VTE while using COC (PILGRIM study). A great number of clinical and biological relevant phenotypes in the field of VTE have already been collected (including 14 polymorphisms selected on the basis of their biological plausibility and the existence association studies).To our knowledge it is the largest study specifically conducted in order to assess genetic factors associated with VTE in women using COC. These 766 cases will be compared to 766 controls from the general population (cohort Nutrinet-Santé). Then, the predictive values of the score will be assessed in an independent multicentric validation study that the investigators will set up in the field of this project. Our study should allow a better understanding of the genetic and environmental factors involved in VTE related to COC use. Besides, this project aims to respond to a major public health issue giving an effective tool for the decision of prescribing COC.

Official Title
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Construction and External Validation of a Predictive Clinico-biological Score of the Risk of Venous Thrombosis in Women Under Combined Oral Contraceptives

Conditions
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Venous Thromboembolism

Intervention / Treatment
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* Biological: blood samples


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Women who had an episode of documented VTE (deep vein thrombosis and / or pulmonary embolism) under COC who consulted in a specialized counseling center. Women of age. Subject agreeing to participate in this research, having signed informed consent. Exclusion Criteria: Absence of COC, No knowledge of the COC generation used by the patient, Undocumented MTEV Episode Absence of available sample (DNA), Refusal to participate in the study

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: controls<br>biological samples bank | Biological: blood samples<br>* blood samples<br>|
| Experimental: cases<br> | Biological: blood samples<br>* blood samples<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Build a predictive score for VTE in women using COC | this score is based on clinical and biological factors | 42 months |