The study population consisted of 18 well-characterized OSA patients and 12 age-matched and weight-matched healthy control subjects. All subjects were white and recruited from the Sleep Laboratory of the Institute of Respiratory Diseases of the University of Bari, Italy. Written informed consent was obtained from all subjects, and the study was approved by the institutional ethics committee. A complete physical examination was performed, including neurologic, cardiopulmonary, and ear, nose, and throat examinations. Inclusion criteria for this study were an apnea-hypopnea index (AHI) of >20 and symptoms of excessive daytime sleepiness, and an AHI of < 5 for control subjects.

The control group consisted of 12 obese subjects who were free of sleep disturbances and were in good health. The OSA patients and the control subjects did not have any endocrinologic diseases, psychiatric disorder, overt cardiopulmonary disease, airway obstruction, anatomic maxillomandibular skeletal abnormalities, or ear, nose, and throat disease Kamagra Pharmacy. None of the subjects were heavy drinkers or used of any kind of drug. Patients with rhinitis, sinusitis, respiratory infections, and systemic infections also were excluded. All subjects had stopped smoking at least 3 months before entering the study and had received no therapy for 4 weeks prior to study entry with inhaled, oral, or nasal steroids or other anti-inflammatory drugs. Exhaled breath condensate was collected in all OSA patients and healthy control subjects before sleeping (8:00 pm) and on waking (8:00 am), and a venous blood sample was taken at the same time.

Ten subjects, who had a diagnosis of OSA based on polysomnography were rehospitalized for CPAP nasal treatment for two nights within 1 week of the diagnostic (baseline) polysomnography. Exhaled breath condensate was collected before and after receiving two nights of CPAP therapy.

Pulmonary function tests were performed within 1 day of the breath condensate measurements. FEV1, FVC, and FEV1/FVC ratio were measured using a spirometer. The best value of three maneuvers was expressed as a percentage of the predicted normal value.