title: Fatigue in fibromyalgia: a conceptual model informed by patient interviews.
abstract: BACKGROUND
  Fatigue is increasingly recognized as an important symptom in fibromyalgia (FM). Unknown however is how fatigue is experienced by individuals in the context of FM. We conducted qualitative research in order to better understand aspects of fatigue that might be unique to FM as well as the impact it has on patients' lives. The data obtained informed the development of a conceptual model of fatigue in FM.
  
  
  METHODS
  Open-ended interviews were conducted with 40 individuals with FM (US [n = 20], Germany [n = 10] and France [n = 10]). Transcripts were analyzed using qualitative methods based upon grounded theory to identify key themes and concepts.
  
  
  RESULTS
  Participants were mostly female (70%) with a mean age of 48.7 years (range: 25-79). Thirty-one individuals (i.e., 77.5%) spontaneously described experiencing tiredness/lack of energy/fatigue due to FM. Participants discussed FM fatigue as being more severe, constant/persistent and unpredictable than normal tiredness. The conceptual model depicts the key elements of fatigue in FM from a patient perspective. This includes: an overwhelming feeling of tiredness (n = 17, 42.5%), not relieved by resting/sleeping (n = 15, 37.5%), not proportional to effort exerted (n = 25, 62.5%), associated with a feeling of weakness/heaviness (n = 20, 50%), interferes with motivation (n = 22, 55%), interferes with desired activities (n = 27, 67.5%), prolongs tasks (n = 15, 37.5%), and makes it difficult to concentrate (n = 21, 52.5%), think clearly (n = 12, 30%) or remember things (n = 9, 22.5%).
  
  
  CONCLUSIONS
  The majority of individuals with FM who participated in this study experience fatigue and describe it as more severe than normal tiredness.
authors.affiliation: Mapi Values, Adelphi Mill, Bollington, Macclesfield Cheshire SK10 5JB, UK. louise.humphrey@mapivalues.com
authors.forename: Louise
authors.initials: L
authors.lastname: Humphrey
authors.forename: Rob
authors.initials: R
authors.lastname: Arbuckle
authors.forename: Philip
authors.initials: P
authors.lastname: Mease
authors.forename: David A
authors.initials: DA
authors.lastname: Williams
authors.forename: Bente Danneskiold
authors.initials: BD
authors.lastname: Samsoe
authors.forename: Claire
authors.initials: C
authors.lastname: Gilbert
mesh_terms: D000328:Adult; D000368:Aged; D015897:Comorbidity / Q000639:trends; D015673:Fatigue Syndrome, Chronic / Q000175:diagnosis* / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D006801:Humans; D007406:Interview, Psychological / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008960:Models, Psychological