title: [Impact of the fibromyalgia in the chronic fatigue syndrome].
abstract: OBJECTIVE
  Different studies have showed association of the chronic fatigue syndrome (CFS) with other pathologies, including fibromyalgia (FM). The objective of this study is to analyze whether there are differences in the clinic and in the assessment of fatigue in CFS patients associated or not with FM.
  
  
  METHODS
  A cross-sectional, single-site observational study was undertaken on a consecutive cases of a register of CFS patients at CFS Unit in Vall d'Hebron Hospital, Barcelona, from January 2008 until March 2011. The variables analyzed were FM comorbidity, sleep and fatigue characteristics and cognitive, neurological and autonomic symptoms. Questionnaires of fatigue impact scale, fatigue strength and impact on quality of life SF-36 were evaluated.
  
  
  RESULTS
  We included 980 CFS patients (mean age: 48±9 years; 91% women). Fibromyalgia was present in 528 patients (54%). The level of fatigue (P=.001) and pain (P<.001) was higher in FM patients. Patients with CFS and FM had more prevalence of sleep-related phenomena. The percentage of patients and the degree of severity of cognitive symptoms, neurological and autonomic dysfunction was higher in FM patients (P<.001). FM patients scored higher on the fatigue impact scale (P<.001) and showed worse results in the quality of life questionnaire (P<.001).
  
  
  CONCLUSIONS
  FM co-morbidity worse clinical parameters, fatigue and the perception of quality of life in CFS patients.
authors.affiliation: EAP CAP Terrassa Nord, Consorci Sanitari de Terrassa, Terrassa, Barcelona, España. Electronic address: 34174mfc@comb.cat.
authors.forename: Mónica
authors.initials: M
authors.lastname: Faro
authors.affiliation: Unidad de Fatiga Crónica, Institut de Recerca Vall d'Hebron, Hospital Universitario Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Naia
authors.initials: N
authors.lastname: Sáez-Francàs
authors.affiliation: Unidad de Fatiga Crónica, Institut de Recerca Vall d'Hebron, Hospital Universitario Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Jesús
authors.initials: J
authors.lastname: Castro-Marrero
authors.affiliation: Unidad de Fatiga Crónica, Institut de Recerca Vall d'Hebron, Hospital Universitario Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: Luisa
authors.initials: L
authors.lastname: Aliste
authors.affiliation: Unidad de Fibromialgia, Hospital Clínic de Barcelona, Barcelona, España.
authors.forename: Antonio
authors.initials: A
authors.lastname: Collado
authors.affiliation: Unidad de Fatiga Crónica, Institut de Recerca Vall d'Hebron, Hospital Universitario Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, España.
authors.forename: José
authors.initials: J
authors.lastname: Alegre
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D015673:Fatigue Syndrome, Chronic / Q000150:complications*; D005260:Female; D005356:Fibromyalgia / Q000150:complications* / Q000175:diagnosis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires
keywords: Calidad de vida; Chronic fatigue syndrome; Comorbidity; Comorbilidad; Fibromialgia; Fibromyalgia; Quality of life; Síndrome de fatiga crónica