Comparison of lung morphology in COPD secondary to cigarette and biomass smoke

OBJECTIVE: To compare lung morphology in chronic obstructive pulmonary disease (COPD) secondary to cigarette smoke (CS) and biomass smoke (BS). METHODS: Necropsies of women with COPD diagnosis by lung pathology and unique exposure to BS (n = 27) or CS (n = 21) matched by age and place of origin. Lungs were macroscopically and microscopically examined to evaluate the extent of emphysema, pigment deposition, and abnormalities in pulmonary arteries, large airways (including the Reid index) and small airways (SAWS) by a semiquantitative method. RESULTS: Both groups had variable degrees of emphysema and SAWS disease. Patients exposed to BS had more lung fibrosis and pigment deposition and thicker pulmonary arterial intima than smokers, who had more emphysema and epithelial damage (goblet cell metaplasia). The Reid index was similar in both groups. CONCLUSION: Lengthy exposure to BS can produce emphysema and other lesions typically observed in cigarette smokers, but with a slightly different distribution. Whether the differences observed are the consequence of severity of exposure or smoke composition, or both, remains to be clarified.