Acute Effect of Aclidinium on Hyperinflation and Ventilation Inhomogeneity in Severe COPD Patients

Chronic Obstructive Pulmonary Disease (COPD) is characterized by lung hyperinflation and flow limitation. These physiopathological modifications are secondary to loss of elastic recoil and bronchial obstruction due to emphysema.

The cornerstone of COPD treatment is represented by inhaled beta-2 agonists and anticholinergics. The molecules of the latter classes can be characterized by short lasting action (few hours), long acting action (12 hours) or ultra long acting duration of action (24 hours).

For years the only anticholinergic (or antimuscarinic) drug other than those used by aerosol, was Tiotropium Bromide. Recently two new antimuscarinic agents have been launched on the market: glycopyrronium bromide (once daily) and aclidinium (twice daily).

The Single Breath Nitrogen Test is capable of identifying the pulmonary closing volume. The part of the curve that reflects lung ventilation inhomogeneity is the slope of phase III

For COPD patients, the most important characteristic for an inhalatory drug is a prompt action in order to give a quick relief from respiratory symptoms, in particular dyspnoea.

The objective of this study is to study the acute action of glycopyrronium and aclidinium in terms of reduction of hyperinflation, pulmonary specific resistances, lung volume distribution and dyspnoea at rest in severe COPD patients.

To our knowledge no study has explored these aspects before.