Evaluate the Effects of Formoterol and Beclomethasone Dipropionate Combination Therapy on Small Airways Function

Inclusion Criteria

• •clinical diagnosis COPD according to last updated GOLD guidelines (post- bronchodilator FEV/FVC below 0,70, FEV1 \<80% predicted)
• •ex-smokers (ie 1 year from the last cigarette) with at least 10 pack years.
• •GOLD stage II and III (FEV1 \> 30% predicted)
• •by preference naïve to inhaled corticosteroids; in those taking inhaled corticosteroids this medication will be stopped 1 month prior to enrollment in the study
• •Patients must have proven small airways dysfunction on routine spirometry as reflected by a drop in FEF25-75 and FEF75 of at least 50%. Moreover, patients must have proven small airways dysfunction on MBW as reflected by Sacin \>0,120 that is considered abnormal.