PRevalence of Obstructive Sleep apnoEa and Reduction of Promoters in AF

This study aims to identify how many patients who have atrial fibrillation, also have sleep apnoea. This is important because sleep apnoea can be a trigger to atrial fibrillation and it can be corrected with a simple intervention. Therefore it is important to understand its prevalence (how many patients with atrial fibrillation are affected by it). Also, obesity and sleep disorders are often associated, therefore the evolution of atrial fibrillation is studied in patients who also have obesity and have lost weight compared with patients who did not loose any weight or are not obese. As medications or therapy are not changed, this is an observational study.