Atrial fibrillation (AF) is the most common sustained rhythm disturbance, increasing prevalence with age, in particular in patients
with cardiovascular disease. On the other hand, a subset of patients with AF being <60 years old and no evidence of underlying
cardiovascular disease, and laboratory tests including thyroid function, echocardiography and exercise” test is well described. This is the
called lone AF, where there is no previous cardiovascular disease, and the etiology is unknown. However, in the last years, some new
factors have been related to play a role or be associated to incident AF. Conditions such as obesity, sleep apnea, alcohol intake, exercise
practice, or genetic factors are associated with the development of this common arrhythmia and make the exclusion diagnosis of lone AF
more complicated. The aim of the present manuscript is to provide an overview of these new risk factors for AF, which are becoming of
special interest in the study of this common arrhythmia.