Clinical and microbiological characteristics and inflammatory profile during an exacerbation of COPD due to biomass exposure. A comparison with COPD due to tobacco exposure

BackgroundPatients with biomass exposure-related COPD (BE-COPD) is a prevalent disease in developing countries and requires a detailed study of its clinical and inflammatory characteristics, specifying interventions that may differ from tobacco exposure-related COPD (TE-COPD). The objective was to describe clinical characteristics, biomarkers of inflammation, T-helper cells, and microbiological agents during a COPD exacerbation in BE-COPD in comparison with TE-COPD.MethodsA prospective observational study in patients with moderate or severe exacerbation was recruited either in the emergency room or the COPD clinic. At enrollment, nasopharyngeal swabs and sputum were collected to identify viral and bacterial pathogens. Blood samples were also collected to measure inflammatory biomarkers and T-helper cells levels. Days of hospitalization and mechanical ventilation requirement was evaluated.ResultsClinical characteristics, vaccination history, hospitalization, history of exacerbations, and microbiological pattern between BE-COPD and TE-COPD were similar. The Th2 profile was higher in BE-COPD than in TE-COPD (2.10 [range 1.30–3.30] vs. 1.40 [range 1.20–1.80], p = 0.001). The Th2/Th1 ratio was higher in BE-COPD than TE-COPD (1.22 [range 0.58–2.57 ] vs. 0.71 [range 0.40–1.15], p = 0.004). The need of mechanical ventilation (MV) was higher in TE-COPD than BE-COPD (13% vs. 31.1%, p = 0.01). Nonvaccination history and high CRP levels were significantly associated with hospitalization [OR 1.48 (CI 95% 1.30–4.61, p = 0.005) and OR 1.17 (CI 95% 1.10–1.24, p = 0.001), respectively].ConclusionsClinical characteristics, inflammatory markers, and microbiological isolates were similar in both groups but BE-COPD show a tendency to present higher inflammatory Th2 cells and low requirement MV compared with TE-COPD.