Atrial fibrillation (AF) is the most common cardiac arrhythmia in the general population. It is associated with an increase in mortality and morbidity, such as stroke and heart failure, and is linked to reduced quality of life and impaired cognitive functions. The Swiss-AF cohort aims to generate new insights into the interrelationships between AF, structural brain alterations and cognitive decline based on a long-term perspective. This will help to define new solutions for this crucial public health issue. Swiss-AF is funded by the Swiss National Science Foundation (SNSF).