A comparison in a Saskatchewan population between clinical diagnosis of asthma and American Thoracic Society Forced Expiratory Volume at one second (FEV1) post-bronchodilator improvement criteria

Gjevre, J. A. (John Anker) (2008) A comparison in a Saskatchewan population between clinical diagnosis of asthma and American Thoracic Society Forced Expiratory Volume at one second (FEV1) post-bronchodilator improvement criteria. Masters thesis, Memorial University of Newfoundland.

[English] PDF - Accepted Version Available under License - The author retains copyright ownership and moral rights in this thesis. Neither the thesis nor substantial extracts from it may be printed or otherwise reproduced without the author's permission. Download (3MB)

Abstract

Background: The diagnosis of asthma can be challenging and is based on clinical symptoms, physical examination, and pulmonary function tests. Most patients with asthma will have a significant post-bronchodilator response on spirometry indicating airway hyper-responsiveness. However, having a significant bronchodilator response by itself is not diagnostic of asthma. Also, the definition of a "significant" response is controversial. Many respirologists use the American Thoracic Society (ATS) post-bronchodilator response criteria of 12% (provided it is ≥ 200 ml) improvement in FEV1 (or FCV) from the baseline spirometry. -- Methods: This study retrospectively reviewed 644 patients who met the ATS criteria for a significant post-bronchodilator spirometric response. The staff respirologist's diagnosis of asthma, based on all clinical and pulmonary function data, was used as the standard for the diagnosis of asthma. -- Results: It was found that relying on spirometric criteria alone was inadequate in asthma diagnosis as only 54.7% of 310 patients meeting ATS bronchodilator response criteria were felt to have asthma clinically. Increasing the post-bronchodilator percent improvement from the ATS criteria only marginally improved diagnostic specificity and resulted in a decline in sensitivity. -- Conclusions: This further emphasizes the need to use spirometric criteria as a guide but not as an unimpeachable gold standard by which to make a diagnosis of asthma. The diagnosis of asthma depends on a combination of expert physician correlation of history, physical examination, and pulmonary function test results.

Actions (login required)

View Item