Glomerular Filtration Rate-Estimating Equations During Use of Direct Oral Anticoagulants in Elderly Patients

Study Overview
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Brief Summary
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Atrial fibrillation in the elderly is a complex condition due to the high number of frequently associated comorbidities such kidney disease. Direct oral anticoagulants (dabigatran, rivaroxaban and apixaban) are indicated for preventing thromboembolic events but renal function should be closely monitored for this age group when these drugs are used. Dosing recommendations for prevention of stroke are based on renal clearance of creatinine (ClCr) estimated using the Cockcroft-Gault formula. It is well known that ClCr estimates predict a steeper decline with advancing age than Glomerular Filtration Rate (GFR) estimates. This raises the possibility that substitution of commonly reported GFR for estimated CrCl could result in different plasmatic concentrations of oral direct anticoagulants. The aim of this study was to compare estimates of ClCr and GFR and determine the impact on the plasmatic concentration of these drugs in elderly patients with non-valvular atrial fibrillation.

Official Title
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Impact of the Choice of Glomerular Filtration Rate-Estimating Equations on Plasmatic Concentrations of Direct Oral Anticoagulants in Elderly Patients With Atrial Fibrillation

Conditions
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Atrial Fibrillation, Elderly Patients, Chronic Kidney Disease

Intervention / Treatment
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* Other: Blood sample


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with non-valvular atrial fibrillation -treated with dabigatran, rivaroxaban or apixaban - patients affiliated to national social health system -patients who agreed to ethical concerns of the study Exclusion Criteria: Patients with consultation or hospitalization that made impossible a veinous punction at the steady state residual concentration time -Patients under guardianship or trusteeship

Ages Eligible for Study
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Minimum Age: 65 Years
Maximum Age: 99 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 |
| --- | --- |
| Blood sample<br> | Other: Blood sample<br>* 2 additional tubes of blood samples are collected during a blood sample realized for the patient's care<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| renal function estimated by different glomerular filtration rate equations and by clearance of creatinine formula |  | At the inclusion | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| plasmatic activity of direct oral anticoagulant at steady state residual time (anti-Xa or anti-IIa) |  | At the inclusion | 
| plasmatic concentration of direct oral anticoagulant at steady state residual time |  | At the inclusion | 
| Number of haemorrhagic or thrombotic adverse events (serious or not) affecting patients | Reported by a trained physician after a phone interview with the patient coupled with medication adherence assessment using 6-item Moriksy scale. An internal questionnaire will be used to collect data. | At 1 month | 
| Number of haemorrhagic or thrombotic adverse events (serious or not) and unexpected events affecting patients | Reported by a trained physician after a phone interview with the general practitioner and the patient coupled with medication adherence assessment using 6-item Moriksy scale. An internal questionnaire will be used to collect data. | At 6 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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direct oral anticoagulants, atrial fibrillation, renal function, ckd-epi, plasmatic concentration