Exhaled carbon monoxide as a marker of lung aging in smokers presenting with mild air flow limitation

Background The measurement of exhaled carbon monoxide (CO) level may provide an immediate, noninvasive method of assessing smoking status. In addition CO is a molecule generally presumed to be a marker of oxidative stress and inflammation when endogenously produced. Many reports have focused on increased endogenous CO production in pulmonary diseases, including asthma and COPD. The purpose of our study is to highlight special characteristics in smokers with mild airflow limitation, in correlation with exhaled CO measurements.