2. Methods
2.1. Study Population
Forty subjects participated in the study; 32 (27 were male) had stable COPD and 8 were healthy subjects (4 were
A. I. El Gammal et al.
21
male). Subjects with concomitant diseases such as infection, heart failure, cancer, severe endocrine, hepatic, or
renal diseases, and systemic autoimmune or connective tissue disorders were excluded from the study. All patients
were stable for at least 3 months. The control subjects with normal pulmonary function had never smoked.
The medical treatment of patients at the time of the study mainly included inhaled therapy in the form of
long-acting β2 agonists, anticholinergic and corticosteroids. Four patients were on regular systemic corticosteroids
and five were on supplemental oxygen therapy. Written, informed consent was obtained and the study was
approved by the Clinical Research Ethics Committee of Cork Teaching Hospitals (ECM 4 (e) 01/08/06). The
study was started on the 1st August 2006 and was completed on the 30th June 2008.