Inclusion Criteria:  Age between 40-80 years [0,0] days Diagnosis of COPD [all available data, 0] days Clinical history of at least 1 COPD exacerbation [all available data, -43] days  Exclusion Criteria:  COPD exacerbation [-42, 0] days Asthma, eczema, atopic dermatitis, allergic rhinitis [-180, 0] days Known respiratory disorder other than COPD e.g. pulmonary fibrosis or interstitial lung disease (ILD), sarcoidosis, lymphangioleiomyomatosis, primary/pulmonary tuberculosis, cystic fibrosis, pulmonary hypertension/other pulmonary heart disease, lung/pulmonary malignancies, alpha-1 antitrypsin deficiency, pneumoconioses and other lung diseases due to external agents [all available data, 0] days Narrow angle glaucoma or prostatic hyperplasia or obstruction of the neck of the bladder [-180, 0] days At least one 30-day supply prescription claims for oral alfuzosin, doxazosin, tamsulosin, silodosin, finasteride 5 mg, dutasteride [-180,0] days Lung transplant or lung volume reduction surgery (LVRS) [all available data, 0] days Daily long term oxygen therapy (LTOT) [all available data, 0] days Beta-blockers (except eye drops) [-180, 0] days Evidence of alcohol, drug or solvent abuse [-180, 0] days Use of salmeterol, tiotropium and fluticasone containing inhaler use [-180, 0] days