title: [Etiology and pathophysiology of fibromyalgia syndrome and chronic widespread pain].
abstract: OBJECTIVE
  To write a systematic review on the etiology and pathophysiology of the fibromyalgia syndrome (FMS) and of chronic widespread pain (CWP).
  
  
  METHODS
  An interdisciplinary level-3 guideline (i.e. systematic literature search and assessment, logic analysis, formal consensus procedure) for the diagnosis and therapy of FMS was created in cooperation with 10 medical and psychological societies and 2 patient self-help organizations. A literature search was performed covering all available review articles on the etiology and pathophysiology of FMS and CWP using the Cochrane Collaboration Reviews (1993-12/2006), Medline (1980-2006), PsychInfo (1966-12/2006), and Scopus (1980-12/2006). For the assignment of evidence classes the system of the Oxford Centre for Evidence-Based Medicine was applied. Consensus was achieved by a multi-step nominal group procedure.
  
  
  RESULTS
  FMS aggregates in families (evidence level 2c). Physical and psychological stress at the workplace are risk factors for the development of CWP and FMS. Affective disorders are risk factors for the development and maintenance of FMS. Operant learning mechanisms and sensitization are risk factors for the chronification of FMS (evidence levels 2b). Several factors are associated with the pathophysiology of FMS, but the causal relationship is unclear. This includes alterations of central pain pathways, hyporeactivity of the hypothalamus-pituitary-adrenal axis, increased systemic pro-inflammatory and reduced anti-inflammatory cytokine profiles and disturbances in the dopaminergic and serotonergic systems.
  
  
  CONCLUSIONS
  FMS is the common final product of various etiological factors and pathophysiological mechanisms.
authors.affiliation: Neurologische Klinik, Universität Würzburg, Würzburg. sommer@mail.uni-wuerzburg.de
authors.forename: C
authors.initials: C
authors.lastname: Sommer
authors.forename: W
authors.initials: W
authors.lastname: Häuser
authors.forename: K
authors.initials: K
authors.lastname: Gerhold
authors.forename: P
authors.initials: P
authors.lastname: Joraschky
authors.forename: F
authors.initials: F
authors.lastname: Petzke
authors.forename: T
authors.initials: T
authors.lastname: Tölle
authors.forename: N
authors.initials: N
authors.lastname: Uçeyler
authors.forename: A
authors.initials: A
authors.lastname: Winkelmann
authors.forename: K
authors.initials: K
authors.lastname: Thieme
mesh_terms: D001341:Autonomic Nervous System / Q000503:physiopathology; D002490:Central Nervous System / Q000503:physiopathology; D003937:Diagnosis, Differential; D019317:Evidence-Based Medicine; D005356:Fibromyalgia / Q000175:diagnosis / Q000209:etiology* / Q000503:physiopathology / Q000523:psychology; D020022:Genetic Predisposition to Disease; D005858:Germany; D006801:Humans; D010348:Patient Care Team; D012307:Risk Factors; D012931:Social Environment; D013315:Stress, Psychological