Does the expired-air carbon monoxide level reflect the severity of inflammation in COPD?

Objectives: The aim of this study is to evaluate the expired-air carbon monoxide level which relates to the severity of inflammation in patients with chronic obstructive pulmonary disease (COPD). Design: Cross sectional study. Setting: Cukurova University, Faculty of Medicine, Department of Chest Disease, Out-patient clinic. Patients: The characteristics of patients enrolled in this study were following; 20 ex-smokers with stable COPD (mean age: 68.8 +/- 7.2 years, FEV1: 45.6 +/- 16.6 % of predicted), 22 current smokers with stable COPD (mean age: 58.7 +/- 8.2 years, FEV1: 57.5 +/- 20.9 % of predicted), 20 healthy smokers (mean age: 55.9 +/- 6.0 years, FEV1: 86.7 +/- 14.2 % of predicted), and 20 healthy non-smokers (mean age: 60.8 +/- 9.2 years, FEV1: 95.3 +/- 13.5 % of predicted). Intervention: CO level was measured in expired-air. Measurement and results: The measurement of expired-air CO level was measured by DisCOver, carbon monoxide analyser. It is known that the level of expired-air carbon monoxide in healthy smokers (11.8 +/- 6.4 ppm) and in current smokers with COPD (11.1 +/- 7.4 ppm) is higher than in healthy non-smokers (1.7 +/- 0.7 ppm) and in ex-smokers with COPD (2.0 +/- 1.8 ppm) (p=0.0001). Conclusion: We assumed that the level of expired-air carbon monoxide may not useful in assessing the severity of inflammation in COPD (Tab. 1, Fig. 2, Ref. 23). Full Text (Free, PDF) www.bmj.sk.