Lack of Correlation Between Pulmonary and Systemic Inflammation Markers in Patients with Chronic Obstructive Pulmonary Disease: A Simultaneous, Two-Compartmental Analysis. / Ausencia de correlación entre marcadores de inflamación pulmonar y sistémica en pacientes con enfermedad pulmonar obstructiva crónica: un análisis bi-compartimental simultáneo.

ABSTRACT

INTRODUCTION: The origin of systemic inflammation in chronic obstructive pulmonary disease (COPD) patients remains to be defined, but one of the most widely accepted hypothesis is the 'spill over' of inflammatory mediators from the lung to the circulation. OBJECTIVE: To evaluate the relationship between pulmonary and systemic inflammation in COPD quantifying several inflammatory markers in sputum and serum determined simultaneously. METHODOLOGY: Correlations between various inflammatory variables (TNF-α, IL6, IL8) in sputum and serum were evaluated in 133 patients from the PAC-COPD cohort study. A secondary objective was the evaluation of relationships between inflammatory variables and lung function. RESULTS: Inflammatory markers were clearly higher in sputum than in serum. No significant correlation was found (absolute value, r=0.03-0.24) between inflammatory markers in blood and in sputum. There were no significant associations identified between those markers and lung function variables, such as FEV1, DLCO and PaO2 neither. CONCLUSIONS: We found no correlation between pulmonary and systemic inflammation in patients with stable COPD, suggesting different pathogenic mechanisms.