title: Distribution of clinical phenotypes in patients with chronic obstructive pulmonary disease caused by biomass and tobacco smoke.
abstract: BACKGROUND
  Exposure to biomass smoke is a risk factor for chronic obstructive pulmonary disease (COPD). It is unknown whether COPD caused by biomass smoke has different characteristics to COPD caused by tobacco smoke.
  
  
  OBJECTIVE
  To determine clinical differences between these two types of the disease.
  
  
  METHODS
  Retrospective observational study of 499 patients with a diagnosis of COPD due to biomass or tobacco smoke. The clinical variables of both groups were compared.
  
  
  RESULTS
  There were 122 subjects (24.4%) in the biomass smoke group and 377 (75.5%) in the tobacco smoke group. In the tobacco group, the percentage of males was higher (91.2% vs 41.8%, P<.0001) and the age was lower (70.6 vs 76.2 years, P<.0001). Body mass index and FEV1% values were higher in the biomass group (29.4±5.7 vs 28.0±5.1, P=.01, and 55.6±15.6 vs 47.1±17.1, P<.0001, respectively). The mixed COPD-asthma phenotype was more common in the biomass group (21.3% vs 5%, P<.0001), although this difference disappeared when corrected for gender. The emphysema phenotype was more common in the tobacco group (45.9% vs 31.9%, P=.009). The prevalence of the chronic bronchitis and exacerbator phenotypes, the comorbidity burden and the rate of hospital admissions were the same in both groups.
  
  
  CONCLUSIONS
  Differences were observed between COPD caused by biomass and COPD caused by tobacco smoke, although these may be attributed in part to uneven gender distribution between the groups.
authors.affiliation: Servicio de Neumología, Hospital Universitario Lucus Augusti, Lugo, España. Electronic address: rafael.golpe.gomez@sergas.es.
authors.forename: Rafael
authors.initials: R
authors.lastname: Golpe
authors.affiliation: Servicio de Neumología, Hospital Universitario Lucus Augusti, Lugo, España.
authors.forename: Pilar
authors.initials: P
authors.lastname: Sanjuán López
authors.affiliation: Servicio de Neumología, Hospital Universitario Lucus Augusti, Lugo, España.
authors.forename: Esteban
authors.initials: E
authors.lastname: Cano Jiménez
authors.affiliation: Servicio de Neumología, Hospital Universitario Lucus Augusti, Lugo, España.
authors.forename: Olalla
authors.initials: O
authors.lastname: Castro Añón
authors.affiliation: Servicio de Neumología, Hospital Universitario Lucus Augusti, Lugo, España.
authors.forename: Luis A
authors.initials: LA
authors.lastname: Pérez de Llano
mesh_terms: D001249:Asthma / Q000453:epidemiology / Q000209:etiology*; D018533:Biomass; D015992:Body Mass Index; D001991:Bronchitis / Q000150:complications; D002908:Chronic Disease; D015897:Comorbidity; D004781:Environmental Exposure; D005260:Female; D005541:Forced Expiratory Volume; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D010641:Phenotype; D015995:Prevalence; D029424:Pulmonary Disease, Chronic Obstructive / Q000453:epidemiology / Q000209:etiology*; D011656:Pulmonary Emphysema / Q000453:epidemiology / Q000209:etiology*; D012189:Retrospective Studies; D012906:Smoke / Q000009:adverse effects*; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D014028:Tobacco Smoke Pollution / Q000009:adverse effects; D014934:Wood
chemical_list: D012906:Smoke; D014028:Tobacco Smoke Pollution
keywords: Biomasa; Biomass; Chronic obstructive pulmonary disease; Comorbidity; Comorbilidad; Enfermedad pulmonar obstructiva crónica; Fenotipos; Phenotypes; Tabaco; Tobacco