Biomarkers and Epigenetic Markers Associated With Pain in Patients With Symptomatic Atrial Fibrillation

Study Overview
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Brief Summary
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Atrial fibrillation (AF) is the most common sustained arrhythmia and the number of patients with AF is expected to increase substantially in the coming decades. One third of patients with AF report no AF-associated symptoms, but up to one-fourth report severe symptoms. It is unclear why patients' experience of AF-related symptoms varies so much. We have previously shown that patients with symptomatic AF exhibit lower pain tolerance than patients with asymptomatic AF, as well as impaired pain inhibitory control and facilitated summation of pain, indicating that pain sensitisation may be of importance in symptomatic AF. In patients with chronic pain conditions, several biomarkers and epigenetic markers associated with generation and /or maintenance of chronic pain have been identified. Previous research of biomarkers and epigenetic markers associated with pain is sparse in patients with AF. The objective is to study levels of biomarkers and epigenetic markers in blood in patients with symptomatic paroxysmal AF (n=100), in relation to severity of AF symptoms, and compared to age- and sex-matched controls without AF (n=100). Blood will be obtained before and after AF ablation and levels of biomarkers, epigenetic markers and cardiac and inflammatory markers, analysed. Patients will complete an AF-specific symptom and a generic health-related quality of life questionnaire. In the future, biomarkers and epigenetic markers associated with pain may be used as a tool for evaluation of patients with AF and have an impact on individualized management. Another possibility is a rationale for future studies of novel analgesics that neutralize biomarkers or antagonizes its receptors.

Official Title
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Biomarkers and Epigenetic Markers Associated With Pain in Patients With Symptomatic Atrial Fibrillation Compared With Controls

Conditions
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Atrial Fibrillation

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: On waiting list for AF ablation (only symptomatic subjects are offered ablation) Paroxysmal AF and persistent AF (AF that is continuously sustained beyond 7 days, including episodes terminated by cardioversion after ≥7 days) Written informed consent Exclusion Criteria: Previous pulmonary vein isolation Cognitive or psychiatric condition Diabetes mellitus Ischemic heart disease Heart failure Asthma Pregnancy Previous/current drug or alcohol abuse Previous neurological or concomitant musculoskeletal disorders Continuous analgesic medication

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Atrial fibrillation<br>Subjects with symptomatic paroxysmal atrial fibrillation scheduled for AF ablation at Örebro University hospital | |
| Control<br>Sex and age-matched subjects without AF | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Biomarkers and epigenetic markers associated with pain | Blood tests will be obtained from subjects the day before, and the day after a planned AF ablation. A total of 30 ml of blood will be obtained at each occasion. The samples will be studied for the association of biomarkers and epigenetic markers to the severity of AF symptoms. Blood samples will be obtained from participants without AF (controls). Biomarkers and epigenetic markers will be compared between the control group and the group with symptomatic AF. | 3 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation of age, sex, AF duration, health-related quality of life to biomarkers and epigenetic markers. |  | 1 day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Atrial fibrillation, Symptoms, Quality of life, Pain