Clinical features and longitudinal assessment in outcomes of chronic obstructive pulmonary disease with biomass smoke exposure history: A prospective study of the RealDTC cohort

OBJECTIVE: This study aimed to explore clinical characteristics and outcomes among patients with biomass smoke-related chronic obstructive pulmonary disease (BS-COPD), those with cigarette smoke-related COPD (CS-COPD), and those exposed to both (CS+BS-COPD). The outcomes of patients receiving different inhaled drugs was also explored. METHODS: This was a real-world, combined cross-sectional and prospective observational study conducted within the RealDTC cohort. The participants were divided into BS-COPD, CS-COPD, and CS+BS-COPD groups. Study outcomes included symptom improvement, moderate-to-severe exacerbations during 1-year follow-up, and all-cause mortality during the total follow-up period. RESULTS: Among the 4436 eligible patients, compared with the CS-COPD group, the BS-COPD group had more females, higher CAT scores, fewer low attenuation areas (LAA%>5%), but more airway mucus plugs, higher WA%, and higher dPA/A. The CS+BS-COPD group had a higher proportion of LAA%>5% than BS-COPD group and more patients with mucus plugs than CS-COPD group. In the adjusted model, BS-COPD had a lower risk of moderate-to-severe exacerbations than CS-COPD, with similar mortality. The CS+BS-COPD group had a higher incidence of moderate-to-severe exacerbations than the other two groups. Moreover, BS-COPD group experienced greater symptom improvement than the others. Across all groups, LABA+LAMA or ICS+LABA+LAMA were associated with lower exacerbation risk than LAMA alone. CONCLUSIONS: In this real-world study, BS-COPD patients had less emphysema but greater airway wall thickness and more mucus plugs, along with lower exacerbation risk and greater symptom improvement than CS-COPD patients. Combined exposure to both biofuels and cigarette smoke was associated with an aggravated exacerbation risk.