title: Epidemiology of primary and secondary headaches in a Brazilian tertiary-care center.
abstract: OBJECTIVE
  To analyze the demographic features of the population sample, the time of headache complaint until first consultation and the diagnosis of primary and secondary headaches.
  
  
  METHODS
  3328 patients were analyzed retrospectively and divided according to gender, age, race, school instruction, onset of headache until first consultation and diagnosis(ICHD-II, 2004).
  
  
  RESULTS
  Sex ratio (Female/Male) was 4:1, and the mean age was 40.7+/-15 years, without statistical differences between sexes. Approximately 65% of the patients were white and 55% had less than eight years of school instruction. Headache complaint until first consultation ranged from 1 to 5 years in 32.99% patients. The most prevalent diagnosis were migraine (37.98%), tension-type headache-TTH (22.65%) and cluster headache (2.73%).
  
  
  CONCLUSIONS
  There are few data on epidemiological features of headache clinic populations, mainly in developing countries. According to the literature, migraine was more frequent than TTH. It is noteworthy the low school instruction of this sample and time patient spent to seek for specialized attention. Hypnic headache syndrome was seen with an unusual frequency.
authors.affiliation: Division for Investigation and Treatment of Headaches, Escola Paulista de Medicina, Federal University of São Paulo, São Paulo, SP, Brazil. cf.andre@terra.com.br
authors.forename: André Carvalho
authors.initials: AC
authors.lastname: Felício
authors.forename: Denis Bernardi
authors.initials: DB
authors.lastname: Bichuetti
authors.forename: William Adolfo Celso dos
authors.initials: WA
authors.lastname: Santos
authors.forename: Clecio de Oliveira
authors.initials: Cde O
authors.lastname: Godeiro Junior
authors.forename: Luis Fabiano
authors.initials: LF
authors.lastname: Marin
authors.forename: Deusvenir de Souza
authors.initials: Dde S
authors.lastname: Carvalho
mesh_terms: D000328:Adult; D017677:Age Distribution; D000367:Age Factors; D017668:Age of Onset; D001938:Brazil / Q000453:epidemiology; D003027:Cluster Headache / Q000175:diagnosis / Q000453:epidemiology; D004522:Educational Status; D005260:Female; D006261:Headache / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000175:diagnosis / Q000453:epidemiology; D015995:Prevalence; D012189:Retrospective Studies; D017678:Sex Distribution; D012737:Sex Factors; D018781:Tension-Type Headache / Q000175:diagnosis / Q000453:epidemiology