Association between markers of emphysema and more severe chronic obstructive pulmonary disease.

BACKGROUND: The predominant emphysema phenotype is associated with more severe airflow limitation in patients with chronic obstructive pulmonary disease (COPD). A study was undertaken to investigate whether COPD patients, with or without emphysema quantitatively confirmed by high resolution computed tomography (HRCT), have different COPD severity as assessed by the BODE index (body mass index, airflow obstruction, dyspnoea, exercise performance) and inspiratory capacity to total lung capacity ratio (IC/TLC), and by different biological markers of lung parenchymal destruction. METHODS: Twenty six outpatients with COPD and eight healthy non-smokers were examined. Each subject underwent HRCT scanning, pulmonary function tests, cell counts, and measurements of neutrophil elastase, matrix metalloproteinase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 in induced sputum, as well as measurement of desmosine, a marker of elastin degradation in urine, plasma and sputum. RESULTS: Patients with HRCT confirmed emphysema had a higher BODE index and lower IC/TLC ratio than subjects without HRCT confirmed emphysema and controls. Forced expiratory volume in 1 second (FEV(1)), FEV(1)/forced vital capacity ratio, and carbon monoxide transfer coefficient were lower, whereas the number of eosinophils, MMP-9, and the MMP-9/TIMP-1 ratio in sputum were higher in patients with emphysema. In COPD patients the number of sputum eosinophils was the biological variable that correlated positively with the HRCT score of emphysema (p = 0.04). CONCLUSIONS: These results suggest that COPD associated with HRCT confirmed emphysema is characterised by more severe lung function impairment, more intense airway inflammation and, possibly, more serious systemic dysfunction than COPD not associated with HRCT confirmed emphysema.

[Occupational exposure to respiratory irritants and chronic obstructive pulmonary disease]. / Esposizione professionale ad agenti irritanti e sviluppo di broncopneumopatia cronica ostruttiva (BPCO).

Cigarette smoking and occupational exposure to respiratory irritants are the major riskfactors for chronic obstructive pulmonary disease (COPD), which is characterized by small-airway obstruction and destruction of pulmonary parenchyma: emphysema. We studied two groups of subjects: one exposed and the other one not-exposed to respiratory irritants, to investigate the relationship, if any, between occupational exposure and COPD. Subjects underwent high-resolution computed tomography-density mask of the chest to quantify pulmonary emphysema, pulmonary function tests, sputum induction and analysis for cell counts and measurements of metalloproteinase (MMP)-9 and its tissue inhibitor TIMP-1. Subjects with occupational exposure to respiratory irritants had higher residual volume and functional residual capacity, higher total inflammatory cells and neutrophils in induced sputum. By contrast, sputum levels of MMP-9, TIMP-1 and MMP-91TIMP-1 ratio did not differ between the 2 groups. We conclude that sputum induction and analysis could be a useful and non-invasive tool to study and follow subjects with occupational exposure to respiratory irritants.

[Substance P in the sputum of patients with chronic obstructive pulmonary disease and occupational exposure to respiratory irritants]. / Sostanza P nell'escreato di pazienti con broncopneumopatia cronica ostruttiva ed esposizione professionale ad irritanti respiratori.

The role of tachykininis in airway inflammation has been extensively demonstrated in experimental animal models, but evidence in humans is very sparse. The aim of this study was first to quantify the content of substance P (SP) in sputum of a group of patients, with chronic obstructive pulmonary disease and with exposure to occupational irritants. Secondly, to compare them with sputum SP content of a group of control subjects.