SESSION TITLE: COPD Phenotypes
SESSION TYPE: Original Investigation Poster
PRESENTED ON: Saturday, April 16, 2016 at 11:45 AM - 12:45 PM
PURPOSE: To explore the clinical phenotype of airways disease by hierarchical cluster analysis and two-step cluster analysis.
METHODS: A population sample of adults who had wheeze within the last 12 months underwent detailed investigation, including a clinical questionnaire, pulmonary function tests, blood tests (total serum IgE levels and blood eosinophil level) and a peak flow diary. Cluster analysis was carried out on the data set with the subjects defined as described using the following nine variables: 1) pre-bronchodilator FEV1/FVC ratio expressed as a percentage; 2) pre-bronchodilator FEV1 expressed as a percentage of the predicted value; 3) post-bronchodilator change in FEV1, expressed as percentage from baseline; 4) residual capacity expressed as a percentage of the predicted value; 5) diffusing capacity of the lung for carbon monoxide/alveolar volume adjusted for haemoglobin level and expressed as a percentage of the predicted value; 6) the serum IgE level; 7) the variability of PEF; 8) respiratory symptoms; 9) cumulative tobacco cigarette consumption.