Influenza Vaccination in Fibromyalgia Patients

Fibromyalgia is a clinical syndrome characterized by the presence of chronic widespread pain accompanied by tenderness and fatigue. Central sensitization is considered to be a major pathogenetic feature of fibromyalgia. While the etiology of fibromyalgia is incompletely understood, it is generally considered to result from the interaction between an appropriate genetic background and the exposure of a susceptible individual to various inciting "triggers". These have included among others physical trauma, infection, stress etc. The possible role of vaccination in causing or exacerbating fibromyalgia has been previously raised. Thus, gulf war syndrome, an entity with considerable clinical overlap with fibromyalgia, has been considered to have a possible link with the exposure to multiple vaccinations. More recently a theory has been advanced regarding the possibility that vaccination - related adjuvants may induce a multisystem disorder characterized by symptoms such as fatigue, cognitive impairment and arthralgia (the so called ASIA syndrome). The investigators have previously established the safety and efficacy of influenza vaccination in Rheumatoid arthritis patients. In view of this background it is of considerable clinical importance to ascertain both the efficacy and safety of vaccination in patients suffering from fibromyalgia.