[Identification of new diagnostic categories within bronchial asthma and COPD. A review of traditional...

The overlapping of function test results and clinical symptoms of airway diseases makes it difficult to differentiate sub-categories of diagnoses. Our aim was to identify "occult" categories within the traditional diagnostic labels for bronchial asthma and chronic bronchitis. We studied 211 patients with those diagnoses by lung function testing (spirometry), variability of obstruction (bronchodilator test, peak expiratory flow, and bronchial challenge testing), atopy (prick test, total serum IgE), biological parameters (eosinophil count), frequency of smoking and symptoms. Multivariant analysis was used to group the data (Quick Cluster) and reclassify the subjects based on the selected parametric clusters with factorial analysis of the principal components. This analysis allowed us to identify four types of patients by diagnosis (atopic asthma, asthmatic bronchitis, simple chronic bronchitis and hyperresponsive chronic bronchitis) which we consider to represent the diagnostic categories with clinical relevance and which would overlap and be partially overshadowed by the diagnoses of bronchial asthma and chronic bronchitis.