Diagnostic Tests for Asthma in Firefighters.
Chest. 2007 Mar 30;
Miedinger D, Chhajed PN, Tamm M, Stolz D, Surber C, Leuppi JD.
Clinic for Pneumology, University Hospital, Basel, Switzerland.
Background: Subjects with asthma do not meet medical requirements for professions such as firefighting.
Objective: To prospectively determine the diagnostic value of respiratory symptoms and various tests used in the assessment of asthma in a cohort of firefighters.
Methods: A questionnaire, spirometry, direct and indirect airway challenge tests, exhaled nitric oxide, exhaled monoxide and skin prick tests were administered prospectively to 101 out of 107 firefighters employed in Basel, Switzerland. Asthma was defined as the combination of respiratory symptoms with airway hyperresponsiveness.
Results: Six out of 101 (6%) firefighters had physician diagnosed asthma, which could be confirmed in four. In contrast 14% (14/101) of all firefighters were diagnosed to have asthma. Wheezing was the most sensitive symptom for the diagnosis of asthma (sensitivity 78%; specificity 93%). Other respiratory symptoms showed a higher specificity than wheezing but a markedly lower sensitivity. Bronchial airway challenge with mannitol was the most sensitive (92%) and specific (97%) diagnostic test for asthma. Using a cut-off point of 47ppb, nitric oxide had a similar specifity (96%) but lower sensitivity (42%) compared to the direct (methacholine) and indirect (mannitol) airway challenge tests.
Conclusion: Asthma was considerably under diagnosed in firefighters. The combination of a structured symptom questionnaire with a bronchial challenge test allows to identify patients with asthma and should routinely be used in the assessment of active firefighters and may be of help when evaluating candidates for this profession.