Airway reactivity and diving in healthy and atopic subjects

Med Sci Sports Exerc. 2003 Sep;35(9):1493-8. doi: 10.1249/01.MSS.0000084424.67486.5B.


Background: The short- and long-term effects of self-contained underwater breathing apparatus (SCUBA) dives on airway responsiveness in nonasthmatic atopic subjects have not been systematically investigated.

Purpose: To compare the effect of SCUBA diving at 50-m depth on lung function and airway responsiveness to methacholine (MCh) in atopic nonasthmatics and healthy subjects.

Methods: We studied 15 atopic nonasthmatic subjects and 15 controls who underwent the visit for the professional SCUBA-diving license at the Navy Medical Center, La Spezia, Italy. All subjects underwent spirometry and skin-prick test for common environmental allergens. MCh challenge was performed 24 h before, and 20 min and 24 h after a standardized SCUBA-dive test and after hyperbaric-chamber test.

Results: At 20 min, the provocative dose of MCh causing 20% fall of the forced expiratory volume at the first second (MCh PD20 - FEV1) was significantly reduced in atopic, asymptomatic subjects from 1712 x 2.6 microg (mean x geometric standard deviation) to 1202 x 2.2 microg (P < 0.0005) after the hyperbaric-chamber test and to 1204 x 2.3 microg (P < 0.005) after SCUBA diving. In healthy subjects, the baseline value of MCh PD20 was 2977 x 1.1 microg, and this value did not change significantly after the hyperbaric-chamber test (2575 x 1.4 microg) and after SCUBA dives (2553 x 1.4 microg, P > 0.1 for both comparisons). In atopic subjects, the MCh PD20 returned near to the baseline value 24 h after the hyperbaric-chamber test (1776 x 2.4 microg) and after the SCUBA test (1500 x 2.67 microg). No significant change in FEV1 was observed after the tests in both groups.

Conclusion: SCUBA diving is associated with development of early airway hyperresponsiveness to MCh in atopic subjects.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Asthma / complications*
  • Asthma / etiology
  • Bronchial Hyperreactivity / etiology*
  • Bronchial Hyperreactivity / physiopathology
  • Bronchial Provocation Tests
  • Bronchoconstrictor Agents
  • Case-Control Studies
  • Diving / physiology*
  • Humans
  • Hypersensitivity, Immediate / complications*
  • Male
  • Methacholine Chloride


  • Bronchoconstrictor Agents
  • Methacholine Chloride