Systemic Endothelial Abnormalities in COPD

Patients with moderate and severe COPD (GOLD stage II and III) will be studied and their results will be compared with age-matched healthy non- smokers and smokers. RAAP will be taken every 5 minutes for 15 minutes before salbutamol and every 5 minutes for another 15 minutes after salbutamol. Several parameters of lipoprotein profiles, anti-oxidant plasma capacity, inflammatory cytokines, hormones, growth factors and vascular cell adhesion molecules will be studied in blood. In addition, several inflammatory and oxidative markers will be studied in exhaled breath condensate. Lung function and impulse oscillometry will be made to investigate airway resistance, and exhaled NO (nitric oxide) at different expiratory flows will be measured to assess alveolar and bronchial NO. Clinical assessment including dyspnoea and depression scores will also be made.