Survey to determine the efficacy and safety of guideline-based pharmacological therapy for chronic obstructive pulmonary disease patients not previously receiving maintenance treatment

To investigate the potential beneficial effects of guideline-based pharmacological therapy on pulmonary function and quality of life (QOL) in Japanese chronic obstructive pulmonary disease (COPD) patients without prior treatment.Multicenter survey, open-label study of 49 Japanese COPD patients aged ≥ 40 years; outpatients with >10 pack years of smoking history; ratio of forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) < 70%; predicted FEV1 < 80%; treated with bronchodilators and/or inhaled corticosteroids as maintenance therapy until week 48.The primary endpoint was change in pulmonary function (trough FEV1, trough FVC); secondary endpoints were QOL and physical activity at 48 weeks after initiation of therapy.Airway reversibility was confirmed in untreated patients. Significant changes over time were not observed for FEV1 and FVC, indicating lung function at initiation of treatment was maintained during the observation period. COPD assessment test scores showed statistical and clinical improvements. Cough, sputum, breathlessness, and shortness of breath were significantly improved.Lung function and QOL of untreated Japanese COPD patients improved and improvements were maintained by performing a therapeutic intervention that conformed to published guidelines.