title: What is chronic headache in the general population? The Akershus study of chronic headache.
abstract: BACKGROUND
  Studies of chronic headache including both primary and secondary causes from the general population is lacking.
  
  
  OBJECTIVE
  To provide prevalence data on chronic headache.
  
  
  METHODS
  We studied chronic headaches defined as headache 15 days per month on average for at least 3 months in the general population. An age and gender stratified random sample of 30,000 persons aged 30-44 years received a mailed questionnaire. Those with self-reported headache on 15 days or more within the last month and/or headache on more than 180 days within the last year were invited to an interview and examination by a neurological resident. The criteria of the International Classification of Headache Disorders were applied.
  
  
  RESULTS
  Chronic headache occurred in 3.71% of the general population.Women had chronic headache twice as often as men. About half of those with chronic headache also had medication overuse, irrespectively of the types of chronic headache. Secondary chronic headaches attributed to chronic rhinosinusitis, head injury, whiplash injury and cervicogenic headache were relatively frequent, i.e. from 1 of 300 to 1 of 600 persons from the general population.
  
  
  CONCLUSIONS
  Primary and secondary chronics headaches should not be ignored.
  
  
  CONCLUSIONS
  Primary and secondary chronic headaches are common in the general population.
authors: Head and Neck Research Group, Research Centre, Akershus University Hospital, Oslo, Norway.
authors: K
authors: K
authors: Aaseth
authors: R B
authors: RB
authors: Grande
authors: C
authors: C
authors: Lundqvist
authors: M B
authors: MB
authors: Russell
mesh_terms: D000328:Adult; D005260:Female; D020773:Headache Disorders / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D009664:Norway / Q000453:epidemiology; D012737:Sex Factors