title: Pain and pressure pain thresholds in adolescents with chronic fatigue syndrome and healthy controls: a cross-sectional study.
abstract: OBJECTIVE
  Although pain is a significant symptom in chronic fatigue syndrome (CFS), pain is poorly understood in adolescents with CFS. The aim of this study was to explore pain distribution and prevalence, pain intensity and its functional interference in everyday life, as well as pressure pain thresholds (PPT) in adolescents with CFS and compare this with a control group of healthy adolescents (HC).
  
  
  METHODS
  This is a case-control, cross-sectional study on pain including 120 adolescents with CFS and 39 HCs, aged 12-18 years. We measured pain frequency, pain severity and pain interference using self-reporting questionnaires. PPT was measured using pressure algometry. Data were collected from March 2010 until October 2012 as part of the Norwegian Study of Chronic Fatigue Syndrome in Adolescents: Pathophysiology and Intervention Trial.
  
  
  RESULTS
  Adolescents with CFS had significantly lower PPTs compared with HCs (p<0.001). The Pain Severity Score and the Pain Interference Score were significantly higher in adolescents with CFS compared with HCs (p<0.001). Almost all adolescents with CFS experienced headache, abdominal pain and/or pain in muscles and joints. Moreover, in all sites, the pain intensity levels were significantly higher than in HCs (p<0.001).
  
  
  CONCLUSIONS
  We found a higher prevalence of severe pain among adolescents with CFS and lowered pain thresholds compared with HCs. The mechanisms, however, are still obscure. Large longitudinal population surveys are warranted measuring pain thresholds prior to the onset of CFS.
  
  
  BACKGROUND
  Clinical Trials, NCT01040429; The Norwegian Study of Chronic Fatigue Syndrome in Adolescents: Pathophysiology and Intervention Trial (NorCAPITAL) http://www.clinicaltrials.gov.
authors.affiliation: Faculty of Health Sciences, Institute of Nursing, Oslo and Akershus University College of Applied Sciences, Oslo, Norway.
authors.forename: Anette
authors.initials: A
authors.lastname: Winger
authors.affiliation: Department of Clinical Medicine, University of Tromsø, The Arctic University of Norway, Tromsø, Norway.
authors.forename: Gunnvald
authors.initials: G
authors.lastname: Kvarstein
authors.affiliation: Medical Faculty, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.|Department of Pediatrics, Oslo University Hospital, Norway.|Department of Pediatrics, Akershus University Hospital, Norway.
authors.forename: Vegard Bruun
authors.initials: VB
authors.lastname: Wyller
authors.affiliation: Department of Pediatrics, Oslo University Hospital, Norway.|Department of Pediatrics, Lillehammer County Hospital, Lillehammer, Norway.
authors.forename: Dag
authors.initials: D
authors.lastname: Sulheim
authors.affiliation: Medical Faculty, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
authors.forename: Even
authors.initials: E
authors.lastname: Fagermoen
authors.affiliation: Faculty of Health Sciences, Institute of Nursing, Oslo and Akershus University College of Applied Sciences, Oslo, Norway.
authors.forename: Milada Cvancarova
authors.initials: MC
authors.lastname: Småstuen
authors.affiliation: Faculty of Health Sciences, Institute of Nursing, Oslo and Akershus University College of Applied Sciences, Oslo, Norway.
authors.forename: Sølvi
authors.initials: S
authors.lastname: Helseth
mesh_terms: D000203:Activities of Daily Living; D000293:Adolescent; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D015673:Fatigue Syndrome, Chronic / Q000150:complications* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D009664:Norway / Q000453:epidemiology; D010146:Pain / Q000453:epidemiology / Q000209:etiology*; D010147:Pain Measurement; D017288:Pain Threshold; D015995:Prevalence; D011795:Surveys and Questionnaires
keywords: PAIN MANAGEMENT; PUBLIC HEALTH