title: Smoking is Associated with Higher Disease-related Costs and Lower Health-related Quality of Life in Inflammatory Bowel Disease.
abstract: OBJECTIVE
  Smoking affects the course of inflammatory bowel disease [IBD]. We aimed to study the impact of smoking on IBD-specific costs and health-related quality-of-life [HrQoL] among adults with Crohn's disease [CD] and ulcerative colitis [UC].
  
  
  METHODS
  A large cohort of IBD patients was prospectively followed during 1 year using 3-monthly questionnaires on smoking status, health resources, disease activity and HrQoL. Costs were calculated by multiplying used resources with corresponding unit prices. Healthcare costs, patient costs, productivity losses, disease course items and HrQoL were compared between smokers, never-smokers and ex-smokers, adjusted for potential confounders.
  
  
  RESULTS
  In total, 3030 patients [1558 CD, 1054 UC, 418 IBD-unknown] were enrolled; 16% smoked at baseline. In CD, disease course was more severe among smokers. Smoking was associated with > 30% higher annual societal costs in IBD (€7,905 [95% confidence interval €6,234 - €9,864] vs €6,017 [€5,186 - €6,946] in never-smokers and €5,710 [€4,687 - €6,878] in ex-smokers, p = 0.06 and p = 0.04, respectively). In CD, smoking patients generated the highest societal costs, primarily driven by the use of anti-tumour necrosis factor compounds. In UC, societal costs of smoking patients were comparable to those of non-smokers. Societal costs of IBD patients who quitted smoking > 5 years before inclusion were lower than in patients who quitted within the past 5 years (€ 5,135 [95% CI €4,122 - €6,303] vs €9,342 [€6,010 - €12,788], p = 0.01). In both CD and UC, smoking was associated with a lower HrQoL.
  
  
  CONCLUSIONS
  Smoking is associated with higher societal costs and lower HrQoL in IBD patients. Smoking cessation may result in considerably lower societal costs.
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Severs
authors.affiliation: Julius Centre for Health Sciences and Primary Care, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: M-J J
authors.initials: MJ
authors.lastname: Mangen
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: M E
authors.initials: ME
authors.lastname: van der Valk
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: H H
authors.initials: HH
authors.lastname: Fidder
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Centre Groningen, Groningen, The Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: Dijkstra
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: van der Have
authors.affiliation: Department of Gastroenterology and Hepatology, VU University Medical Centre, Amsterdam, The Netherlands.|Department of Gastroenterology and Hepatology [Co-MIK], Zuyderland Medical Centre, Heerlen, Sittard, Geleen, The Netherlands.
authors.forename: A A
authors.initials: AA
authors.lastname: van Bodegraven
authors.affiliation: Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
authors.forename: D J
authors.initials: DJ
authors.lastname: de Jong
authors.affiliation: Department of Gastroenterology and Hepatology, Erasmus University Medical Centre, Rotterdam, The Netherlands.
authors.forename: C J
authors.initials: CJ
authors.lastname: van der Woude
authors.affiliation: Department of Gastroenterology and Hepatology [Co-MIK], Zuyderland Medical Centre, Heerlen, Sittard, Geleen, The Netherlands.
authors.forename: M J L
authors.initials: MJ
authors.lastname: Romberg-Camps
authors.affiliation: Department of Gastroenterology and Hepatology, Diaconessenhuis, Leiden, The Netherlands.
authors.forename: C H M
authors.initials: CH
authors.lastname: Clemens
authors.affiliation: Department of Gastroenterology and Hepatology, Onze Lieve Vrouwe Gasthuis, Amsterdam, The Netherlands.
authors.forename: J M
authors.initials: JM
authors.lastname: Jansen
authors.affiliation: Department of Gastroenterology and Hepatology, Slingeland Hospital, Doetinchem, The Netherlands.
authors.forename: P C
authors.initials: PC
authors.lastname: van de Meeberg
authors.affiliation: Department of Gastroenterology and Hepatology, Antonius Hospital, Nieuwegein, The Netherlands.
authors.forename: N
authors.initials: N
authors.lastname: Mahmmod
authors.affiliation: Department of Gastroenterology and Hepatology, Academic Medical Centre Amsterdam, Amsterdam, The Netherlands.
authors.forename: C Y
authors.initials: CY
authors.lastname: Ponsioen
authors.affiliation: Department of Gastroenterology and Hepatology, Meander Medical Centre, Amersfoort, The Netherlands.
authors.forename: J R
authors.initials: JR
authors.lastname: Vermeijden
authors.affiliation: Department of Gastroenterology and Hepatology, Leiden University Medical Centre, Leiden, The Netherlands.
authors.forename: A E
authors.initials: AE
authors.lastname: van der Meulen-de Jong
authors.affiliation: Department of Gastroenterology and Hepatology, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Pierik
authors.affiliation: Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
authors.forename: P D
authors.initials: PD
authors.lastname: Siersema
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Centre Utrecht, Utrecht, The Netherlands.
authors.forename: B
authors.initials: B
authors.lastname: Oldenburg
mesh_terms: D000328:Adult; D000368:Aged; D003093:Colitis, Ulcerative / Q000188:drug therapy / Q000191:economics* / Q000453:epidemiology*; D015897:Comorbidity; D017281:Cost of Illness; D003424:Crohn Disease / Q000188:drug therapy / Q000191:economics* / Q000453:epidemiology*; D004526:Efficiency; D004651:Employment / Q000706:statistics & numerical data; D005260:Female; D017048:Health Care Costs; D006295:Health Resources / Q000191:economics / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D011446:Prospective Studies; D011788:Quality of Life; D012720:Severity of Illness Index; D012907:Smoking / Q000191:economics* / Q000453:epidemiology*; D016540:Smoking Cessation / Q000191:economics; D011795:Surveys and Questionnaires; D000067251:Symptom Flare Up
keywords: Crohn’s disease; economic evaluation; health-related quality of life; smoking; ulcerative colitis