Rheumatoid arthritis is a chronic, disabling disease that affects between 0.33 and 1% of the world's population. Ninety percent of RA patients complain of fatigue.Several studies have shown that this symptom is at least as disabling as pain. Fatigue can be present regardless of the intensity of rheumatoid arthritis, and occurs in patients of all ages. Fatigue often leads to weariness and discouragement, and considerably impairs patients' quality of life. According to an ANDAR survey, this symptom, which is widespread and insufficiently taken into account by the medical profession, forces more than 50% of sufferers to reduce or give up certain activities.Fatigue is also a criterion that is not the stated aim of the therapeutic innovation that rheumatoid arthritis and other inflammatory rheumatic diseases have undergone with the advent of biotherapy. As a result, the impact of biotherapy on fatigue is rarely assessed.