title: Reproducibility of acute mountain sickness in children and adults: a prospective study.
abstract: OBJECTIVE
  Although a history of previous acute mountain sickness (AMS) is commonly used for providing advice and recommending its prophylaxis during subsequent exposure, the intraindividual reproducibility of AMS during repeated high-altitude exposure has never been examined in a prospective controlled study.
  
  
  METHODS
  In 27 nonacclimatized children and 29 adults, AMS was assessed during the first 48 hours after rapid ascent to 3450 m on 2 consecutive occasions 9 to 12 months apart.
  
  
  RESULTS
  During the first exposure, 18 adults (62%) and 6 children (22%) suffered from AMS; during the second exposure, 14 adults (48%) and 4 children (15%) suffered from this problem (adults versus children, P ≤ .01). Most importantly, the intraindividual reproducibility of AMS was very different (P < .001) between children and adults. None of the 6 children having suffered from AMS during the first exposure suffered from AMS during the second exposure, but 4 children with no AMS during the first exposure did experience this problem during the second exposure. In contrast, 14 of the 18 adults who suffered from AMS on the first occasion also presented with this problem during the second exposure, and no new case developed in those who had not experienced AMS on the first occasion.
  
  
  CONCLUSIONS
  In adults, a history of AMS is highly predictable of the disease on subsequent exposure, whereas in children it has no predictive value. A history of AMS should not prompt practitioners to advise against reexposure to high altitude or to prescribe drugs for its prophylaxis in children.
authors.affiliation: Department of Internal Medicine, Centre Hospitalier Universitaire Vaudois Lausanne, Switzerland.
authors.forename: Emrush
authors.initials: E
authors.lastname: Rexhaj
authors.forename: Sophie
authors.initials: S
authors.lastname: Garcin
authors.forename: Stefano F
authors.initials: SF
authors.lastname: Rimoldi
authors.forename: Hervé
authors.initials: H
authors.lastname: Duplain
authors.forename: Thomas
authors.initials: T
authors.lastname: Stuber
authors.forename: Yves
authors.initials: Y
authors.lastname: Allemann
authors.forename: Claudio
authors.initials: C
authors.lastname: Sartori
authors.forename: Urs
authors.initials: U
authors.lastname: Scherrer
mesh_terms: D000208:Acute Disease; D000222:Adaptation, Physiological; D000293:Adolescent; D000328:Adult; D000532:Altitude Sickness / Q000175:diagnosis* / Q000453:epidemiology / Q000517:prevention & control; D002648:Child; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011322:Primary Prevention / Q000379:methods*; D011446:Prospective Studies; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D013557:Switzerland / Q000453:epidemiology; D055815:Young Adult