Breath Analysis in Asthma

Inclusion criteria

• Confirmed asthma. Diagnosis of asthma is made with episodic chest symptoms and a documented reversibility of at least 12% and/or 200 ml in FEV1 after 200 ug of inhaled salbutamol or airway hyperresponsiveness in the case of normal lung function testing (PC20 methacholine < 4mg/ml) at the time of diagnosis.
• Age between 18 and 80 years at study entry.
• Healthy controls: never-smokers, normal spirometry (baseline FEV1 > 85% predicted and FEV1/FVC greater than 0.7).

Exclusion criteria

• Asthma exacerbation within the last 6 weeks, defined as worsening of asthma symptoms requiring a change in therapy by a physician or a change in regular asthma therapy (including short course of oral corticosteroids)
• Any lung disease other than asthma.
• Acute inflammatory disease (e.g. common cold) within the last 4 weeks.
• Regular intake of oral steroids.
• Active smoking habits / positive history of smoking.
• Acute or chronic hepatic disease.
• Renal failure or renal replacement therapy.
• Pregnancy.