Evaluation of Exhaled Carbon Monoxide Levels in Smokers and Non-Smokers-A Comparative Study

Background: Cigarette smoke causes both acute and chronic changes of the immune system. Carbon monoxide (CO) exhaled through breath of an individual is an easiest, immediate and non-invasive method to assess smoking status. Aim: The aim of the study is to compare the exhaled CO levels in smokers and non-smokers using portable CO monitor. Material & Methods: The exhaled CO levels were measured in 100 subjects (50 smokers, 50 non-smokers) who were examined during the OPD. Exhaled CO concentration was measured using the Micro+ Smokerlyser. Results: The mean carbon monoxide in the smokers was 6.34 PPM and the mean carbon monoxide in non-smokers was 1.26 PPM. There was statistically very highly significant difference of mean CO among smokers and non-smokers (P<0.001). Conclusion: The exhaled CO levels successfully distinguished smokers from nonsmokers and it provides an easy and non-invasive mode of assessing a subject's smoking status. This will be beneficial for healthcare providers to examine the effectiveness of tobacco cessation and prevention programs.