Hypercoagulable Phenotype by Thrombinography (in Presence of C Protein Dynamic Inhibitory System)

Study Overview
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Brief Summary
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The purpose is to determine the hypercoagulable phenotype by thrombinography associated to an increased risk of symptomatic and objectively confirmed first venous thrombotic event. This is a case-control study in a population with patients having systemic lupus erythematosus (SLE) and/or antiphospholipid antibodies (APL). Secondary purposes are: To determine the frequency of hypercoagulable phenotype in study population; To analyze the sensibility: consequences of variation of hypercoagulable phenotype threshold on the importance of risk; To identify (genetic and not) factors for hypercoagulable phenotype and their frequency in different groups.

Official Title
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Hypercoagulable Phenotype by Thrombinography (in Presence of C Protein Dynamic Inhibitory System): Marker of Venous Thrombosis Risk in Systemic Lupus and Antiphospholipid Syndrome? Case-control Study

Conditions
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Venous Thrombosis

Intervention / Treatment
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* Other: Blood sample


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Cases : Patients with SLE and/or APL and first documented deep vein thrombosis episode (minimum 6 months, maximum 6 years) Any weight and height Absence of current anticoagulant treatment but possibility of platelet function inhibitory treatment; actual guidelines suggest long-term anticoagulant treatment in patients with first episode of venous thrombosis and having APL; however, these patients can be studied if they are in one of these circumstances: 1/ inconvenient stop by patient, 2/ aspirin decided by doctor after prolonged treatment Controls: Patients with SLE and/or APL without thrombosis (venous or arterial) Any weight and height Possibility of platelet function inhibitory treatment (primary prophylaxis of arterial manifestations) Exclusion Criteria: Cases and Controls : Pregnancy Refusal of consent Difficulty of follow-up (not sufficient motivation)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

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: Screening
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Cases<br>Patients with SLE and/or APL and first vein thrombosis episode | Other: Blood sample<br> <br> |
| Other: Controls<br>age-matched; Patients with SLE and/or APL | Other: Blood sample<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Thrombin potential measured with thrombinography |  | baseline | 
| Measurement of IC50-APC (concentration of APC diminishing 50% thrombin potential at APC concentration = 0) |  | baseline | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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systemic lupus erythematosus, antiphospholipid syndrome, antiphospholipid antibodies