title: Smoking and 2-month culture conversion during anti-tuberculosis treatment.
abstract: OBJECTIVE
  To investigate risk factors for delayed sputum culture conversion to negative during anti-tuberculosis treatment, with an emphasis on smoking.
  
  
  METHODS
  Nested case-control study of adults with non-cavitary, culture-confirmed pulmonary tuberculosis (TB) participating in  an anti-tuberculosis treatment trial in Brazil. A case of delayed culture conversion was a patient who remained culture-positive after 2 months of treatment. Odds ratios with 95% confidence intervals were calculated.
  
  
  RESULTS
  Fifty-three cases and 240 control patients were analyzed. Smokers  had three-fold greater odds of remaining culture-positive after 2 months of treatment (P = 0.007) than non-smokers, while smokers and ex-smokers who smoked >20 cigarettes a day had two-fold greater odds of remaining culture-positive after 2 months of treatment (P = 0.045).
  
  
  CONCLUSIONS
  Cigarette smoking adversely affects culture conversion during anti-tuberculosis treatment. Support for smoking cessation should be considered to improve outcomes in TB control programs.
authors: Núcleo de Doenças Infecciosas, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, Vitória, Espírito Santo, Brazil. ethel.maciel@gmail.com
authors: E L
authors: EL
authors: Maciel
authors: A P
authors: AP
authors: Brioschi
authors: R L
authors: RL
authors: Peres
authors: L M
authors: LM
authors: Guidoni
authors: F K
authors: FK
authors: Ribeiro
authors: D J
authors: DJ
authors: Hadad
authors: S A
authors: SA
authors: Vinhas
authors: E
authors: E
authors: Zandonade
authors: M
authors: M
authors: Palaci
authors: R
authors: R
authors: Dietze
authors: J L
authors: JL
authors: Johnson
mesh_terms: D000293:Adolescent; D000328:Adult; D000995:Antitubercular Agents / Q000627:therapeutic use; D001938:Brazil / Q000453:epidemiology; D016001:Confidence Intervals; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000187:drug effects / Q000302:isolation & purification*; D016017:Odds Ratio; D015995:Prevalence; D012189:Retrospective Studies; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects* / Q000453:epidemiology; D016540:Smoking Cessation; D000074606:Smoking Prevention; D013183:Sputum / Q000382:microbiology*; D016896:Treatment Outcome; D014376:Tuberculosis / Q000188:drug therapy* / Q000453:epidemiology / Q000382:microbiology; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents