Differences of clinical characteristics and phenotype between biomass and tobacco related COPD

Abstract

Exposure to biomass smoke is a risk factor for COPD. The aim of the present study is to determine whether COPD caused by biomass smoke has different characteristics to COPD caused by tobacco smoke. COPD patients who apply to our clinic between August 2017 and July 2018 included the study. Patients with history of workplace exposure to inorganic dusts, combined biomass and tobacco exposure and with any other concomitant chronic pulmonary disease excluded. Patients were classified into phenotypes using the Spanish COPD classification guidelines (GesEPOC). Exacerbation rates for last three years were recorded. In the biomass group, the percentage of females was higher (66% vs 18.9%, P=.000). Age did not differ between groups, FEV1 did not also. Arterial oxygen saturation was significantly higher in the tobacco group (88.8% vs 85.9, p=.021); but partial arterial oxygen and carbon-dioxide pressures, and Ph were same in both groups. The exacerbator with chronic bronchitis phenotype was more common in the biomass group (24.5% vs 16%, p=.001), the exacerbator with emphysema phenotype was more common in the tobacco group (20.8% vs 5.7%, P=.003). The prevalence of asthma-COPD overlap, and non-exacerbator phenotypes did not differ between groups, also GOLD groups not. Eosinophilia, pulmonary hypertension, use of long-term oxygen and/or non-invasive ventilator, comorbidity burden, the exacerbation rates were same in both groups. Phenotypes could differ between biomass associated COPD and tobacco associated COPD; but factors determining severity and prognosis of COPD, -including pulmonary hypertension, use of long-term oxygen and non-invasive ventilator, and exacerbation rates-, are similar.