Prevalence and Clinical Associates of Iron Deficiency in Patients With Atrial Fibrillation

Study Overview
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Brief Summary
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To estimate the prevalence of iron deficiency (ID) in patients with atrial fibrillation

Detailed Description
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Atrial fibrillation is the most frequent chronic arrhythmia with an increasing prevalence in developed and developing countries. Estimated number of individuals living with chronic atrial fibrillation is 33 million globally. In developed and developing countries, the number of elderly individuals increases steadily and the incidence varies from 0.21 to 0.41/1000 person-years depending on regional differences. Approximately half of atrial fibrillation cases are permanent (chronic), 25% are paroxysmal (ending within one week), and 25% are persistant atrial fibrillation (ending for a week, spontaneous or intervention). Symptoms and signs of atrial fibrillation vary between individuals, and the clinical picture appears in a wide range of conditions ranging from asymptomatic events to thromboembolic events or patients with severe heart failure. The most common symptoms are; palpitations, fatigue, exercise intolerance, and systemic thromboembolic events in patients who do not receive appropriate anticoagulant treatment. Long-term follow-up, especially in persistent and permanent atrial fibrillation patients results in preserved ejection fraction heart failure and right heart failure. Prevention of thromboembolic events is the most important approach. Patients with paroxysmal, persistent and permanent atrial fibrillation have to take life-long oral anticoagulation therapy if they are at high risk for developing thromboembolic events. In patients with oral anticoagulant therapy, the risk of bleeding increases and hemorrhagic events are seen, ranging from life threatening asymptomatic blood loss to lethal cerebral hemorrhage. Atrial fibrillation is considered as a chronic inflammatory disease. Both in general population and in patients with cardiac diseases, inflammatory mediators can alter atrial electrophysiology and structure, and thereby increase the tendency to develop atrial fibrillation. Enormous number of studies showed a clear association between inflammatory markers and thromboembolic events in atrial fibrillation. Anemia is a frequently encountered problem in atrial fibrillation patients with a prevalence of 12.3%. Existing studies suggested an association between anemia and thromboembolic events in atrial fibrillation. However, current evidence supports that it is a marker for increased risk of bleeding after anticoagulant therapy, and two bleeding risk scores (ATRIA and HEAMORRHAGES) included presence of anemia as a component of risk assessment. Despite of a clear association between anemia and unfavorable events in atrial fibrillation, none of the studies determined the type anemia in these patients so far. In a preliminary single center study, with relatively limited number of cases (n = 101), it is shown that 47.6% of patients with atrial fibrillation had ID according to the criteria used for heart failure patients. B12 (9.9%) and folic acid (12.9%) deficiencies were less frequent Again in the same study, the prevalence of ID was found to be twice as frequent as the paroxysmal atrial fibrillation group in the permanent atrial fibrillation group, suggesting that ID is associated with high sensitive C-reactive protein and N-terminal proBNP levels. The validation of this study findings in a larger, non-retrospective case-group and the clinical determinants of ID in patients with atrial fibrillation will be useful in the clinical evaluation of patients and in planning possible treatment alternatives.

Official Title
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Prevalence and Clinical Associates of Iron Deficiency in Patients With Atrial Fibrillation (AID-AF)

Conditions
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Iron-deficiency, Atrial Fibrillation

Intervention / Treatment
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* Diagnostic Test: Ferritin, iron and iron binding capacity, high sensitive C-reactive protein (CRP) measurement


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with paroxysmal, persistent and permanent non-valvular atrial fibrillation Men and women aged over 18 years Left ventricular ejection fraction >0.50 Exclusion Criteria: Left ventricular ejection fraction <0.50 Patients with overt symptoms and signs of heart failure Patients with a known chronic inflammatory disease Patients with hemodynamically significant valvular heart disease Patients who had received management for iron deficiency in the preceding 12 months

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

| Intervention/Treatment |
| --- |
|Diagnostic Test: Ferritin, iron and iron binding capacity, high sensitive C-reactive protein (CRP) measurement|Ferritin, iron and iron binding capacity will be measured for evaluation of ID using Cobas c-e and Elecsys. The relation of inflammation to iron deficiency will be evaluated by high sensitive C-reactive protein measurement.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Prevalence of iron deficiency in patients with atrial fibrillation | To estimate the prevalence of iron deficiency in patients with atrial fibrillation | At enrollment | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Assessment of the prevalence of iron deficiency in patients with paroxysmal, persistent and permanent atrial fibrillation | To estimate the prevalence of iron deficiency in patients with paroxysmal, persistent and permanent atrial fibrillation at enrollment. | At enrollment | 
| Assessment of the relation of iron deficiency to functional capacity | The functional capacity of the patients will be assessed with 6-minute walk test | At enrollment | 
| Assessment of the relation of iron deficiency to thromboembolic risk score | Thromboembolic risks will be assessed using CHADSVASC score | At enrollment | 
| Assessment of the relation of iron deficiency to bleeding risk score | Bleeding risks will be assessed using HASBLED score | At enrollment | 
| Assessment of the relation of iron deficiency to hs-CRP level | hs-CRP level (milligram/Liter) will be measured in patients with paroxysmal, persistent and permanent atrial fibrillation at enrollment | At enrollment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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iron deficiency, atrial fibrillation