All of the following interventions are demonstrated to effect natural history of patients with COPD, except

Only three interventions--smoking cessation, oxygen therapy in chronically hypoxemic patients, and lung volume reduction surgery in selected patients with emphysema--have been demonstrated to influence the natural history of patients with COPD. There is currently suggestive, but not definitive, evidence that the use of inhaled glucocoicoids may alter moality rate (but not lung function).All other current therapies are directed at improving symptoms and decreasing the frequency and severity of exacerbations. In general, bronchodilators are used for symptomatic benefit in patients with COPDRef: Harrison 19e pg: 1705