title: Is obstructive sleep apnea syndrome associated with headache?
abstract: OBJECTIVE
  Obstructive sleep apnea syndrome (OSA) is a common disorder in the general population. Although the mechanisms remain obscure, an association with headache has been reported. We aimed to assess the frequency of OSA in a population of headache patients based on a stratified sampling technique using questionnaire and polysomnography (PSG).
  
  
  METHODS
  The survey was provided to new outpatients examined by a neurologist for headache over a 2-year period of time. The patients completed a headache diary during 30 days and those at risk of OSA went through a PSG examination.
  
  
  RESULTS
  Of 903 headache patients, 75 reported heavy snoring and episodes of interrupted nocturnal breathing (8%). Among 43 patients examined with PSG, 14 (1.5% of the total study population) had an apnea/hypopnea index of 5 or higher. Eleven of the patients reported morning headache.
  
  
  CONCLUSIONS
  The frequency of OSA in a patients referred to specialist for headache problems is not higher than what is reported for the general population. The relatively low rate of OSA in this selected group of patients with headache referred to neurology for second opinion does not support the notion that OSA brings about headache.
authors.affiliation: Department of Neurology, Tromsø University Hospital Department of Neurology, Nordland Central Hospital, Bodø, University of Tromsø, Tromsø, Norway. svein.ivar.bekkelund@unn.no
authors.forename: R
authors.initials: R
authors.lastname: Jensen
authors.forename: C
authors.initials: C
authors.lastname: Olsborg
authors.forename: R
authors.initials: R
authors.lastname: Salvesen
authors.forename: T
authors.initials: T
authors.lastname: Torbergsen
authors.forename: S I
authors.initials: SI
authors.lastname: Bekkelund
mesh_terms: D000328:Adult; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D005260:Female; D006261:Headache / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009664:Norway; D017286:Polysomnography; D012017:Referral and Consultation / Q000706:statistics & numerical data; D012307:Risk Factors; D020181:Sleep Apnea, Obstructive / Q000175:diagnosis* / Q000453:epidemiology