Assessment of Induced Sputum Cellularity in COPD Patients Belonging to Two Different Classes of Air Pollution Exposure

Introduction: Several studies have previously demonstrated that long-term exposure to outdoor pollution present airway inflammation in term of an increase of sputum neutrophils.

Aim and methods: The aim of our study was to evaluate the level of airway inflammation by induced sputum in a group of 15 non-professionally exposed population of well-characterized COPD patients, residing in urban areas with high rate of outdoor pollution, compared to a control group of 13 individuals with COPD, living in rural areas with a low pollution rate. All participants underwent spirometry and sputum induction.

Results: A statistically significant increase in the percentage of neutrophil cell count was found among the residents in urban areas compared to those living in rural regions (89.1 vs 79.0, p<0.05) CONCLUSIONS: In conclusion, we showed that non-professionally exposed patients with COPD residing in highly-polluted urban areas had greater airway inflammation in terms of sputum neutrophils compared to a population with very similar characteristics, living in rural areas with lower outdoor pollution. The results of this pilot study may be relevant for the long term effect of environmental outdoor pollution in vulnerable patients like those with COPD.