title: Effect of smoking and indoor air pollution on the risk of tuberculosis: smoking, indoor air pollution and tuberculosis.
abstract: BACKGROUND
  Although epidemiological studies have reported an association between smoking and increases in tuberculosis, the relationship between indoor air pollution and risk of tuberculosis is not fully understood. A limited number of studies have suggested that smoking and indoor air pollution may play a role in the pathogenesis of tuberculosis. In this study, we investigated the effect of smoking and indoor air pollution on the risk of active tuberculosis.
  
  
  METHODS
  It is prospectively recorded age matched case-control study. Three hundred sixty two active tuberculosis cases and 409 healthy controls were included to the study. All participants were interviewed face to face by using a questionnaire including smoking habit, quantity and duration of smoking, number of room/person in the house, monthly income of the family, indoor heating system, and environmental tobacco smoke.
  
  
  RESULTS
  Patients who smoke had a five fold (95% CI: 3.2-7.5, p< 0.0001) higher odds of having active tuberculosis compared with patients who do not smoke. Similarly, patients using coal or wood for indoor heating had a 1.6 fold (95% CI: 1.179-2.305, p< 0.003) higher odds having tuberculosis. People who have less income (< 200 Euro/month) had 3.2 fold (95% CI: 2.113-5.106, p< 0.0001) higher odds of having tuberculosis compared with people having high income. There was a significant correlation between heavy smoking (≥ 20 packet/year, p< 0.0001) and age onset of smoking (< 16 years of age, p< 0.041). There was no significant association between environmental tobacco smoke and tuberculosis.
  
  
  CONCLUSIONS
  Smoking and indoor air pollution may increase the risk of tuberculosis. There is a complex interaction between smoking, socioeconomic conditions, indoor air quality and tuberculosis. Our results suggest that effective indoor air quality control could help to prevent tuberculosis risk.
authors.affiliation: Adult Allergy Unit, Medeniyet University, Goztepe Training and Research Hospital, Istanbul, Turkey. aysebilgeozturk@yahoo.com.
authors.forename: Ayşe Bilge
authors.initials: AB
authors.lastname: Oztürk
authors.forename: Zeki
authors.initials: Z
authors.lastname: Kiliçaslan
authors.forename: Halim
authors.initials: H
authors.lastname: Işsever
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016902:Air Pollution, Indoor / Q000009:adverse effects*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007182:Income; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012306:Risk; D012907:Smoking / Q000009:adverse effects*; D011795:Surveys and Questionnaires; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014397:Tuberculosis, Pulmonary / Q000191:economics / Q000209:etiology*; D014026:Nicotiana
chemical_list: D014028:Tobacco Smoke Pollution