title: Asthma in adventure travelers: a prospective study evaluating the occurrence and risk factors for acute exacerbations.
abstract: BACKGROUND
  Exacerbation of asthma during travel to remote regions may lead to devastating consequences. The course of asthma in travelers and the risk factors for disease exacerbation during travel have not been studied.
  
  
  METHODS
  We screened 5835 consecutive travelers and identified 203 patients with asthma. Before travel, all enrollees were assessed for presumed risk factors for asthma exacerbation by means of an interview and an exercise test combined with spirometry. After travel, data regarding travel characteristics and asthma severity were recorded by means of a structured telephone interview.
  
  
  RESULTS
  The 203 enrollees visited 56 countries for a median duration of 13 weeks, 147 were engaged in high-altitude trekking, and 88 had asthma attacks. Among these, 40 reported worsening asthma during travel, 32 experienced the worst asthma attack ever, and 11 reported a life-threatening asthma attack. Two independent risk factors for attacks during travel were identified: frequent use (> or = 3 times weekly) of inhaled bronchodilators before travel (relative risk [RR], 3.35; 95% confidence interval [CI], 1.75-6.39) and participation in intensive physical exertion during treks (RR, 2.04; 95% CI, 1.04-3.98). When both risk factors were present, the RR for asthma attacks increased to 5.52 (95% CI, 2.81-10.84).
  
  
  CONCLUSIONS
  Asthma frequently worsens during travel and should not be ignored as a potentially life-threatening condition requiring pretravel consideration. Asthmatic travelers who frequently use inhaled bronchodilators before travel or participate in intensive trekking during travel are at increased risk to develop asthma attacks. Therapy should be intensified to achieve better disease control; intensive trekking should be discouraged.
authors.affiliation: Unit of Infectious Diseases and Travel Advisory Clinic, Tel Aviv Sourasky Medical Center, Israel. ygolan@lifespan.org
authors.forename: Yoav
authors.initials: Y
authors.lastname: Golan
authors.forename: Amir
authors.initials: A
authors.lastname: Onn
authors.forename: Yael
authors.initials: Y
authors.lastname: Villa
authors.forename: Yoav
authors.initials: Y
authors.lastname: Avidor
authors.forename: Shmuel
authors.initials: S
authors.lastname: Kivity
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Berger
authors.forename: Itzhak
authors.initials: I
authors.lastname: Shapira
authors.forename: Yoram
authors.initials: Y
authors.lastname: Levo
authors.forename: Michael
authors.initials: M
authors.lastname: Giladi
mesh_terms: D000208:Acute Disease; D000328:Adult; D000704:Analysis of Variance; D001249:Asthma / Q000188:drug therapy / Q000453:epidemiology* / Q000209:etiology* / Q000503:physiopathology / Q000517:prevention & control; D001993:Bronchodilator Agents / Q000008:administration & dosage; D005080:Exercise Test; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D015994:Incidence; D007557:Israel / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012135:Respiratory Sounds / Q000209:etiology; D018570:Risk Assessment; D012307:Risk Factors; D012720:Severity of Illness Index; D013147:Spirometry; D014195:Travel
chemical_list: D001993:Bronchodilator Agents