title: The effect of smoking on tuberculosis: different patterns and poorer outcomes.
abstract: METHODS
  It has been well documented that smoking increases the risk of tuberculosis (TB). However, few studies have evaluated the impact of smoking on TB. We conducted this retrospective study to evaluate the influences of smoking on the manifestation and outcome of TB.
  
  
  METHODS
  All culture-confirmed TB patients from July 2002 to December 2003 were identified and their medical records reviewed.
  
  
  RESULTS
  A total of 523 TB patients, including 207 (39.6%) who had ever smoked, were studied. The ever-smokers were significantly older, more likely to have underlying diseases and a duration of symptoms > 60 days, and less likely to have extra-pulmonary involvement and have completed treatment (64.7% vs. 78.5%). Radiographically, more ever-smokers with pulmonary tuberculosis (PTB) presented with miliary lesions, multiple nodules or masses, upper lung predominance and cavitation than never-smokers. Although smoking was associated with poor prognosis on univariate survival analysis, multivariate analysis revealed that independent poor prognostic factors included age, underlying disease, symptom duration < or = 60 days, extra-pulmonary involvement, serum albumin level < 3.5 g/dl and delayed treatment.
  
  
  CONCLUSIONS
  Our results demonstrate that smoking is significantly associated with radiographic manifestations of PTB, but not with death among PTB patients.
authors.affiliation: Department of Internal Medicinee, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: J Y
authors.initials: JY
authors.lastname: Wang
authors.forename: P R
authors.initials: PR
authors.lastname: Hsueh
authors.forename: I S
authors.initials: IS
authors.lastname: Jan
authors.forename: L N
authors.initials: LN
authors.lastname: Lee
authors.forename: Y S
authors.initials: YS
authors.lastname: Liaw
authors.forename: P C
authors.initials: PC
authors.lastname: Yang
authors.forename: K T
authors.initials: KT
authors.lastname: Luh
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012907:Smoking / Q000453:epidemiology*; D016019:Survival Analysis; D013624:Taiwan / Q000453:epidemiology; D016896:Treatment Outcome; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology* / Q000401:mortality