title: COPD phenotypes in biomass smoke- versus tobacco smoke-exposed Mexican women.
abstract: We hypothesised that biomass smoke exposure is associated with an airway-predominant chronic obstructive pulmonary disease (COPD) phenotype, while tobacco-related COPD is associated with an emphysema-predominant phenotype. In this cross-sectional study, female never-smokers with COPD and biomass exposure (n=21) and female ex-cigarette smokers with COPD without biomass exposure (n=22) completed computed tomography (CT) at inspiration and expiration, pulmonary function, blood gas, exercise tolerance, and quality of life measures. Two radiologists scored the extent of emphysema and air trapping on CT. Quantitative emphysema severity and distribution and airway wall thickness were calculated using specialised software. Women in the tobacco group had significantly more emphysema than the biomass group (radiologist score 2.3 versus 0.7, p=0.001; emphysema on CT 27% versus 19%, p=0.046; and a larger size of emphysematous spaces, p=0.006). Women in the biomass group had significantly more air trapping than the tobacco group (radiologist score 2.6 and 1.5, respectively; p=0.02) and also scored lower on the symptom, activities and confidence domains of the quality of life assessment and had lower oxygen saturation at rest and during exercise (p<0.05). Biomass smoke exposure is associated with less emphysema but more air trapping than tobacco smoke exposure, suggesting an airway-predominant phenotype.
authors.affiliation: University of British Columbia, St Paul's Hospital, Vancouver, BC.
authors.forename: Pat G
authors.initials: PG
authors.lastname: Camp
authors.forename: Alejandra
authors.initials: A
authors.lastname: Ramirez-Venegas
authors.forename: Raul H
authors.initials: RH
authors.lastname: Sansores
authors.forename: Luis F
authors.initials: LF
authors.lastname: Alva
authors.forename: Jill E
authors.initials: JE
authors.lastname: McDougall
authors.forename: Don D
authors.initials: DD
authors.lastname: Sin
authors.forename: Peter D
authors.initials: PD
authors.lastname: Paré
authors.forename: Nestor L
authors.initials: NL
authors.lastname: Müller
authors.forename: C Isabela S
authors.initials: CI
authors.lastname: Silva
authors.forename: Carlos E
authors.initials: CE
authors.lastname: Rojas
authors.forename: Harvey O
authors.initials: HO
authors.lastname: Coxson
mesh_terms: D000368:Aged; D000397:Air Pollution / Q000009:adverse effects*; D001784:Blood Gas Analysis; D003296:Cooking; D003430:Cross-Sectional Studies; D003936:Diagnosis, Computer-Assisted; D004646:Emphysema / Q000150:complications / Q000175:diagnosis; D017079:Exercise Tolerance; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008800:Mexico; D008875:Middle Aged; D015999:Multivariate Analysis; D010641:Phenotype; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000208:ethnology / Q000209:etiology*; D011788:Quality of Life; D012129:Respiratory Function Tests; D012906:Smoke / Q000009:adverse effects*; D012907:Smoking / Q000009:adverse effects*; D014057:Tomography, X-Ray Computed
chemical_list: D012906:Smoke