title: Undiagnosed and comorbid disorders in patients with presumed chronic fatigue syndrome.
abstract: OBJECTIVE
  To assess undiagnosed and comorbid disorders in patients referred to a tertiary care center with a presumed diagnosis of chronic fatigue syndrome (CFS).
  
  
  METHODS
  Patients referred for chronic unexplained fatigue entered an integrated diagnostic pathway, including internal medicine assessment, psychodiagnostic screening, physiotherapeutic assessment and polysomnography+multiple sleep latency testing. Final diagnosis resulted from a multidisciplinary team discussion. Fukuda criteria were used for the diagnosis of CFS, DSM-IV-TR criteria for psychiatric disorders, ICSD-2 criteria for sleep disorders.
  
  
  RESULTS
  Out of 377 patients referred, 279 (74.0%) were included in the study [84.9% female; mean age 38.8years (SD 10.3)]. A diagnosis of unequivocal CFS was made in 23.3%. In 21.1%, CFS was associated with a sleep disorder and/or psychiatric disorder, not invalidating the diagnosis of CFS. A predominant sleep disorder was found in 9.7%, 19.0% had a psychiatric disorder and 20.8% a combination of both. Only 2.2% was diagnosed with a classical internal disease. In the total sample, a sleep disorder was found in 49.8%, especially obstructive sleep apnea syndrome, followed by psychophysiologic insomnia and periodic limb movement disorder. A psychiatric disorder was diagnosed in 45.2%; mostly mood and anxiety disorder.
  
  
  CONCLUSIONS
  A multidisciplinary approach to presumed CFS yields unequivocal CFS in only a minority of patients, and reveals a broad spectrum of exclusionary or comorbid conditions within the domains of sleep medicine and psychiatry. These findings favor a systematic diagnostic approach to CFS, suitable to identify a wide range of diagnostic categories that may be subject to dedicated care.
authors.affiliation: Department of General Internal Medicine, Infectious Diseases and Psychosomatic Medicine, University Hospital Ghent, Belgium; Center for Neurophysiologic Monitoring, University Hospital Ghent, Belgium. Electronic address: an.mariman@ugent.be.
authors.forename: An
authors.initials: A
authors.lastname: Mariman
authors.forename: Liesbeth
authors.initials: L
authors.lastname: Delesie
authors.forename: Els
authors.initials: E
authors.lastname: Tobback
authors.forename: Ignace
authors.initials: I
authors.lastname: Hanoulle
authors.forename: Erica
authors.initials: E
authors.lastname: Sermijn
authors.forename: Peter
authors.initials: P
authors.lastname: Vermeir
authors.forename: Dirk
authors.initials: D
authors.lastname: Pevernagie
authors.forename: Dirk
authors.initials: D
authors.lastname: Vogelaers
mesh_terms: D000328:Adult; D000368:Aged; D015897:Comorbidity; D005221:Fatigue / Q000209:etiology*; D015673:Fatigue Syndrome, Chronic / Q000150:complications* / Q000523:psychology; D005260:Female; D006801:Humans; D033183:Interdisciplinary Communication; D008297:Male; D001523:Mental Disorders / Q000175:diagnosis; D008875:Middle Aged; D010348:Patient Care Team; D017286:Polysomnography; D012890:Sleep; D012893:Sleep Wake Disorders / Q000175:diagnosis; D055815:Young Adult
keywords: AASM; AHI; American Academy of Sleep Medicine; BMI; CDC; CFS; Centers for Disease Control and Prevention; Chronic fatigue syndrome; Comorbidity; DSM-IV-TR; Diagnostic and Statistical Manual of Mental Disorders, 4th edition — text revision; ICSD-2; International Classification of Sleep Disorders, 2nd edition; MSLT; MUS; OSA; PLM; PLMD; PSG; Prevalence; Psychiatric disorders; REM; SD; Sleep disorders; UCF; apnea-hypopnea index; body mass index; chronic fatigue syndrome; medically unexplained symptoms; multiple sleep latency test; obstructive sleep apnea; periodic limb movement disorder; periodic limb movements; polysomnography; rapid eye movements; standard deviation; unexplained chronic fatigue