title: Fatigue and chronic fatigue syndrome-like complaints in the general population.
abstract: BACKGROUND
  Most knowledge on chronic fatigue (CF) and chronic fatigue syndrome (CFS) is based on clinical studies, not representative of the general population. This study aimed to assess the prevalence of fatigue in an adult general population and to identify associations with lifestyle factors.
  
  
  METHODS
  Total 22,500 residents of Nijmegen were selected at random and interviewed by questionnaire. Data on 9062 respondents (43% response) were analysed, taken into account age, gender and concomitant disease. Subjects were classified into four groups: not fatigued (NF, reference group), short-term fatigue (SF, <6 months), chronic fatigue (CF, >or=6 months) and CFS-like fatigue (in accordance with the Center for Disease Control criteria for CFS, without clinical confirmation).
  
  
  RESULTS
  Our study population showed the following breakdown: NF 64.4% (95% CI 63.6-65.6%), SF 4.9% (95% CI 4.5-5.4%), CF 30.5% (95% CI 29.5-31.4%) and CFS-like fatigue 1.0% (95% CI 0.8-1.2%). Compared with the NF group, more of the CFS respondents were female [odds ratio (OR) = 1.9], obese (OR = 4.1), using analgesics (OR = 7.8), had a low alcohol intake (OR = 0.4), were eating less healthy food (OR = 0.5) and were physically less active (OR = 0.1). These associations largely applied to the SF and CF group. The fatigue could have been due to a concomitant disease in 34 and 55.5% of the SF and CF cases, respectively.
  
  
  CONCLUSIONS
  The prevalence of CF in the general population appears to be much higher than previously indicated. Even with strict criteria for CFS, it is estimated that approximately 1% of the adult population experiences this condition. Interestingly, a large part of this group remains unrecognized by the general practitioner. A striking similarity in lifestyle pattern between SF, CF and CFS calls for further research.
authors.affiliation: Department of Epidemiology, Biostatistics and HTA, Radboud University Nijmegen Medical Centre, the Netherlands.
authors.forename: Marjolein
authors.initials: M
authors.lastname: van't Leven
authors.forename: Gerhard A
authors.initials: GA
authors.lastname: Zielhuis
authors.forename: Jos W
authors.initials: JW
authors.lastname: van der Meer
authors.forename: André L
authors.initials: AL
authors.lastname: Verbeek
authors.forename: Gijs
authors.initials: G
authors.lastname: Bleijenberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002908:Chronic Disease; D003430:Cross-Sectional Studies; D004032:Diet / Q000706:statistics & numerical data; D005221:Fatigue / Q000145:classification / Q000453:epidemiology*; D015673:Fatigue Syndrome, Chronic / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008019:Life Style; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D015995:Prevalence; D011788:Quality of Life / Q000523:psychology; D017678:Sex Distribution; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires