title: Alternobaric vertigo: prevalence in Portuguese Air Force pilots.
abstract: CONCLUSIONS
  Having found a prevalence rate of alternobaric vertigo in Portuguese Air Force pilots that is somewhat higher than previously reported, we underline the importance of implementing education on the management of this condition as part of routine Air Force pilot training programs.
  
  
  OBJECTIVE
  Alternobaric vertigo is a condition in which transient vertigo with spatial disorientation occurs suddenly during flying or diving activities, caused by bilateral asymmetrical changes in middle ear pressure. Its prevalence is very likely underestimated and under-reported, with the 10-17% prevalence rate mentioned in early literature not being challenged by recent data.
  
  
  METHODS
  To assess its actual prevalence, the authors requested all high performance aircraft pilots presently on active duty in the Portuguese Air Force to anonymously answer a questionnaire on alternobaric vertigo symptoms, after a short briefing on the subject.
  
  
  RESULTS
  A 29% prevalence rate of in-flight episodes consistent with alternobaric vertigo was obtained.
authors.affiliation: Department of Otorhinolaryngology, Air Force Hospital, Lisbon, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Subtil
authors.forename: Jorge
authors.initials: J
authors.lastname: Varandas
authors.forename: Fernando
authors.initials: F
authors.lastname: Galrão
authors.forename: Alves
authors.initials: A
authors.lastname: Dos Santos
mesh_terms: D000158:Acoustic Impedance Tests; D000328:Adult; D000401:Aircraft; D000532:Altitude Sickness / Q000150:complications* / Q000453:epidemiology / Q000503:physiopathology; D001274:Atmospheric Pressure; D001299:Audiometry; D006801:Humans; D008297:Male; D008889:Military Personnel; D011174:Portugal / Q000453:epidemiology; D015995:Prevalence; D012307:Risk Factors; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D014717:Vertigo / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology