Prevalence of Antiphospholipid Antibodies in the Hemodialysis Patients Population Within the CHU Brugmann Hospital

Study Overview
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Brief Summary
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In patients with a chronic renal disease at the terminal stage, extrarenal epuration is essential for the control of clinico-biological complications. Two extrarenal epuration techniques are currently available: peritoneal dialysis (using the peritoneal membrane of the patient) and hemodialysis, requiring the use of an external biocompatible membrane known as 'dialysis filter'. This technique requires a vascular access (arteriovenous fistula or dialysis catheter). The thrombosis of vascular accesses represents a major cause of morbidity and mortality in hemodialysis patients. Thrombosis are more frequent when using synthetic prosthetic arteriovenous fistula instead of native arteriovenous fistula. Antiphospholipid Syndrome (APLS) is a rare autoimmune disease characterized by arterial thrombosis, venous thrombosis and obstetrical complications such as as defined by the Sidney's criteria. In the general population, the presence of antiphospholipid antibodies is associated with an increased risk of thromboembolic events. In the nephrological population, this prevalence is higher in hemodialysis patients compared to patients on peritoneal dialysis or non-dialyzed patients. Up to 37% of hemodialysis patients are positive for antiphospholipid antibodies and this biology is associated with thrombotic events and vascular access thromboses. However, some studies do not report this association and there is currently no consensus in terms of the therapeutic management of these patients. Some factors influencing the positivity for antiphospholipid antibodies have been reported: smoking, age, the presence of a non-glomerular nephropathy, hypoalbuminaemia, the use of a central venous catheter for dialysis or the use of a non-biocompatible dialysis membrane. Taking into account the conflicting data from the literature, it seems important to study the respective role(s) of 3 types of antiphospholipid antibodies in the occurrence of thrombo- embolic events in patients undergoing dialysis within the CHU Brugmann Hospital.

Official Title
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Retrospective Study of the Prevalence of Antiphospholipid Antibodies in the Population of Hemodialysis Patients at the CHU Brugmann Hospital

Conditions
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Antiphospholipid Syndrome

Intervention / Treatment
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* Other: Data extraction from medical files


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: - All patients undergoing dialysis within the CHU Brugmann Hospital Exclusion Criteria: Mutation of factor V Mutation G20210A of the prothrombin gene Protein C deficiency Protein S deficiency Antithrombin III deficiency

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Positive for antiphospholipid antibodies<br>Patients tested positive for antiphospholipid antibodies | Other: Data extraction from medical files<br>* Retrospective data extraction from the medical files<br>|
| Negative for antiphospholipid antibodies<br>Patients tested negative for antiphospholipid antibodies | Other: Data extraction from medical files<br>* Retrospective data extraction from the medical files<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of antiphospholipid antibodies | Prevalence of antiphospholipid antibodies | 19 years | 
| Prevalence of arterial thrombosis | Prevalence of arterial thrombosis | 19 years | 
| Prevalence of venous thrombosis | Prevalence of venous thrombosis | 19 years | 
| Maturation delay of the arteriovenous fistula | Maturation delay of the arteriovenous fistula | 19 years | 
| Percentage of thrombosis of the filter | Percentage of thrombosis of the filter | 19 years | 
| Lifespan of the catheter | Lifespan of the catheter | 19 years | 
| Lifespan of the fistula | Lifespan of the fistula | 19 years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Existence of thrombosis risk factors | Existence of at least one of the following pro-thrombotic risk factors: smoking, active neoplasia, arterial hypertension. | 19 years | 
| Anticoagulant treatment | Existence of an anticoagulant treatment Presence of an anticoagulant treatment by means of anti-vitamin K | 19 years | 
| Antiplatelet treatment Antiplatelet treatment | Existence of an antiplatelet treatment | 19 years | 
| Antihypertensive treatment | Existence of an antihypertensive treatment | 19 years | 
| Statin treatment | Existence of a treatment by means of statins | 19 years | 
| Ethiology of the nephropathy (known/unknown) | Known versus unknown ethiology | 19 years | 
| Ethiology of the nephropathy (glomerular) | Glomerular versus non-glomerular ethiology | 19 years | 
| Age at dialysis entry | Age at dialysis entry | 19 years | 
| Vascular access | Catheter versus distal arteriovenous fistula versus proximal arteriovenous fistula | 19 years | 
| Type of dialysis | Hemodiafiltration versus conventional hemodialysis | 19 years | 
| Type of per-dialytic anticoagulation | With or without heparin | 19 years | 
| Brand of dialysis membrane | Brand of dialysis membrane | 19 years | 
| Urea change percentage | Urea change percentage | Last available result within 19 years | 
| Activated partial thromboplastin time (aPTT) | Coagulation assessment | Last available result within 19 years | 
| Hemoglobin count | Hemoglobin count | Last available result within 19 years | 
| Platelets count | Platelets count | Last available result within 19 years |