Towards clinical phenotyping of COPD : effects of inhaled corticosteroide in the GLUCOLD study

Abstract

Patients with Chronic Obstructive Pulmonary Disease (COPD) have a lung disorder that limits daily activities and contributes considerably to physical limitations and emotional distress. Taking into account the large heterogeneity of the disease, it can be expected that specific subtypes of the disease (phenotypes) may benefit from a given treatment. This thesis is based on analyses from the Groningen Leiden Universities Corticosteroids in Obstructive Lung Disease (GLUCOLD) study. The effects of long-term maintenance therapy with inhaled corticosteroids with or without long-acting bronchodilators, and discontinuation were examined on 1) clinical parameters: symptoms, lung function decline, airway hyperreactivity and hyperinflation; and 2) pathological parameters: inflammatory cell counts in bronchial biopsies and induced sputum. The current thesis focused on health status, chronic bronchitis, long-term therapy with inhaled corticosteroids and specific phenotypes that benefit from treatment. By showing that certain subgroups of COPD such as patients with less advanced disease or a subphenotype with less emphysema can benefit from inhaled corticosteroids, our results may offer an indication for a promising perspective for particular, individual patients with COPD towards the potential of slowing down the progression of the disease in the future.