title: Impact of Smoking Cessation on the Clinical Course of Crohn's Disease Under Current Therapeutic Algorithms: A Multicenter Prospective Study.
abstract: OBJECTIVE
  Given the importance of tobacco smoking (TS) as the only environmental factor repeatedly linked to the development of the Crohn's disease (CD), it is surprising that very few prospective studies have assessed whether TS is associated with an increased frequency of clinical relapse. Our aim was to evaluate the current impact of TS on disease relapse and the clinical benefit of quitting smoking in the present era of widespread use of anti-TNF drugs and immunosuppressants.
  
  
  METHODS
  This was a multicenter prospective cohort study, which included 573 CD patients in clinical remission with various smoking habits. All smokers were advised to quit. Patients not exposed to tobacco before inclusion (non- and former smokers), continuing smokers, and quitters were compared regarding differences in disease outcomes during a follow-up of 4 years.
  
  
  RESULTS
  A total of 148 continuing smokers, 190 nonsmokers, 160 former smokers, and 75 quitters were included. In comparison with nonsmokers, continuing smokers relapsed more frequently with an incidence rate ratio of 1.53 (95% confidence interval (CI): 1.10-2.17). Former smokers and quitters had similar relapse incidences compared with nonsmokers. Smoking was an independent predictor for disease relapse in the multivariate analysis (hazard ratio: 1.58 (95% CI 1.20-2.09). In the time-dependent analysis, continuing smokers had earlier relapse, regardless of anti-TNF or immunosuppressant use.
  
  
  CONCLUSIONS
  Continuing smokers have more disease relapses, and patients who quit smoking have a similar relapse incidence compared with nonsmokers.
authors: Hospital Clinic Barcelona, IDIBAPS, CIBERehd, Barcelona, Spain.
authors: Tiago
authors: T
authors: Nunes
authors: Hospital Clinic Barcelona, IDIBAPS, CIBERehd, Barcelona, Spain.
authors: Maria Josefina
authors: MJ
authors: Etchevers
authors: Hospital Reina Sofia, Córdoba, Spain.
authors: Valle
authors: V
authors: García-Sánchez
authors: Hospital Universitario Son Espases, Palma de Mallorca, Spain.
authors: Daniel
authors: D
authors: Ginard
authors: Hospital Universitario Son Espases, Palma de Mallorca, Spain.
authors: Eva
authors: E
authors: Martí
authors: Hospital Clinico Universitario, Santiago de Compostela, Spain.
authors: Manuel
authors: M
authors: Barreiro-de Acosta
authors: Hospital Clinico, CIBERehd, Zaragoza, Spain.
authors: Fernando
authors: F
authors: Gomollón
authors: Hospital Clinico, CIBERehd, Zaragoza, Spain.
authors: Maite
authors: M
authors: Arroyo
authors: Hospital La Fe, CIBERehd, Valencia, Spain.
authors: Guillermo
authors: G
authors: Bastida
authors: Hospital Juan Canalejo, A Coruña, Spain.
authors: Benito
authors: B
authors: Gonzalez
authors: Consorci Sanitari de Terrassa, Terrassa, Spain.
authors: David
authors: D
authors: Monfort
authors: Hospital Sant Pau, CIBERehd, Barcelona, Spain.
authors: Esther
authors: E
authors: García-Planella
authors: Hospital Clinic Barcelona, IDIBAPS, CIBERehd, Barcelona, Spain.
authors: Carolina
authors: C
authors: Figueroa
authors: Hospital Clinic Barcelona, IDIBAPS, CIBERehd, Barcelona, Spain.
authors: Julián
authors: J
authors: Panés
authors: Hospital Clinic Barcelona, IDIBAPS, CIBERehd, Barcelona, Spain.|Centro Médico Teknon, Barcelona, Spain.
authors: Miquel
authors: M
authors: Sans
mesh_terms: D000328:Adult; D000465:Algorithms; D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D015331:Cohort Studies; D016001:Confidence Intervals; D003424:Crohn Disease / Q000188:drug therapy / Q000453:epidemiology / Q000523:psychology; D005260:Female; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D055502:Secondary Prevention / Q000379:methods / Q000706:statistics & numerical data; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology / Q000503:physiopathology; D016540:Smoking Cessation / Q000706:statistics & numerical data*; D013030:Spain / Q000453:epidemiology; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*
chemical_list: D000893:Anti-Inflammatory Agents; D007166:Immunosuppressive Agents; D014409:Tumor Necrosis Factor-alpha