title: Exposure to Ambient Air Pollution and the Risk of Inflammatory Bowel Disease: A European Nested Case-Control Study.
abstract: Industrialization has been linked to the etiology of inflammatory bowel disease (IBD).
  
  
  
  We investigated the association between air pollution exposure and IBD.
  
  
  
  The European Prospective Investigation into Cancer and Nutrition cohort was used to identify cases with Crohn's disease (CD) (n = 38) and ulcerative colitis (UC) (n = 104) and controls (n = 568) from Denmark, France, the Netherlands, and the UK, matched for center, gender, age, and date of recruitment. Air pollution data were obtained from the European Study of Cohorts for Air Pollution Effects. Residential exposure was assessed with land-use regression models for particulate matter with diameters of <10 μm (PM10), <2.5 μm (PM2.5), and between 2.5 and 10 μm (PMcoarse), soot (PM2.5 absorbance), nitrogen oxides, and two traffic indicators. Conditional logistic regression analyses were performed to calculate odds ratios (ORs) with 95 % confidence intervals (CIs).
  
  
  
  Although air pollution was not significantly associated with CD or UC separately, the associations were mostly similar. Individuals with IBD were less likely to have higher exposure levels of PM2.5 and PM10, with ORs of 0.24 (95 % CI 0.07-0.81) per 5 μg/m(3) and 0.25 (95 % CI 0.08-0.78) per 10 μg/m(3), respectively. There was an inverse but nonsignificant association for PMcoarse. A higher nearby traffic load was positively associated with IBD [OR 1.60 (95 % CI 1.04-2.46) per 4,000,000 motor vehicles × m per day]. Other air pollutants were positively but not significantly associated with IBD.
  
  
  
  Exposure to air pollution was not found to be consistently associated with IBD.
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands.
authors.forename: Jorrit L
authors.identifier: 0000-0003-2703-7682
authors.initials: JL
authors.lastname: Opstelten
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, P.O. Box 80178, 3508 TD, Utrecht, The Netherlands.|Center for Sustainability, Environment and Health, National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720 BA, Bilthoven, The Netherlands.
authors.forename: Rob M J
authors.initials: RMJ
authors.lastname: Beelen
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, P.O. Box 80178, 3508 TD, Utrecht, The Netherlands.
authors.forename: Max
authors.initials: M
authors.lastname: Leenders
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, P.O. Box 80178, 3508 TD, Utrecht, The Netherlands.
authors.forename: Gerard
authors.initials: G
authors.lastname: Hoek
authors.affiliation: Institute for Risk Assessment Sciences, Utrecht University, P.O. Box 80178, 3508 TD, Utrecht, The Netherlands.
authors.forename: Bert
authors.initials: B
authors.lastname: Brunekreef
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands.
authors.forename: Fiona D M
authors.initials: FDM
authors.lastname: van Schaik
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands.|Department of Gastroenterology and Hepatology, Radboud University Medical Center, P.O. Box 9101, 6500 HB, Nijmegen, The Netherlands.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Siersema
authors.affiliation: Danish Cancer Society Research Center, Strandboulevarden 49, 2100, Copenhagen Ø, Denmark.
authors.forename: Kirsten T
authors.initials: KT
authors.lastname: Eriksen
authors.affiliation: Danish Cancer Society Research Center, Strandboulevarden 49, 2100, Copenhagen Ø, Denmark.|Department of Environmental Science, Aarhus University, Frederiksborgvej 399, 4000, Roskilde, Denmark.
authors.forename: Ole
authors.initials: O
authors.lastname: Raaschou-Nielsen
authors.affiliation: Danish Cancer Society Research Center, Strandboulevarden 49, 2100, Copenhagen Ø, Denmark.
authors.forename: Anne
authors.initials: A
authors.lastname: Tjønneland
authors.affiliation: Section for Epidemiology, Department of Public Health, Aarhus University, Bartholins Allé 2, 8000, Aarhus C, Denmark.
authors.forename: Kim
authors.initials: K
authors.lastname: Overvad
authors.affiliation: Paris-Saclay University, Université Paris-Sud, Université de Versailles-Saint-Quentin-en-Yvelines (UVSQ), Centre de Recherche en Épidémiologie et Santé des Populations (CESP), U1018, Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Gustave Roussy, 114 rue Edouard Vaillant, 94800, Villejuif, France.|Institut Gustave Roussy, 114 Rue Edouard Vaillant, 94805, Villejuif, France.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Boutron-Ruault
authors.affiliation: Paris-Saclay University, Université Paris-Sud, Université de Versailles-Saint-Quentin-en-Yvelines (UVSQ), Centre de Recherche en Épidémiologie et Santé des Populations (CESP), U1018, Institut National de la Santé et de la Recherche Médicale (INSERM), Institut Gustave Roussy, 114 rue Edouard Vaillant, 94800, Villejuif, France.|Institut Gustave Roussy, 114 Rue Edouard Vaillant, 94805, Villejuif, France.|Department of Gastroenterology, Bicêtre University Hospital, Assistance Publique des Hôpitaux de Paris, 78 Rue du Général Leclerc, 94275, Le Kremlin Bicêtre, France.
authors.forename: Franck
authors.initials: F
authors.lastname: Carbonnel
authors.affiliation: Environmental Exposure and Health Unit, Department of Epidemiology and Public Health, Swiss Tropical and Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland.|University of Basel, Petersplatz 1, 4001, Basel, Switzerland.|MRC-PHE Center for Environment and Health, Department of Epidemiology and Biostatistics, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.
authors.forename: Kees
authors.initials: K
authors.lastname: de Hoogh
authors.affiliation: Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Richard Doll Building, Old Road Campus, Oxford, OX3 7LF, UK.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Key
authors.affiliation: Strangeways Research Laboratory, Institute of Public Health, University of Cambridge, Worts Causeway, Cambridge, CB1 8RN, UK.
authors.forename: Robert
authors.initials: R
authors.lastname: Luben
authors.affiliation: Department of Medicine, Faculty of Medicine and Health Sciences, Norwich Medical School, University of East Anglia, Norwich, NR4 7TJ, UK.|Department of Gastroenterology, Norfolk and Norwich University Hospital NHS Trust, Colney Lane, Norwich, NR4 7UY, UK.
authors.forename: Simon S M
authors.initials: SSM
authors.lastname: Chan
authors.affiliation: Department of Medicine, Faculty of Medicine and Health Sciences, Norwich Medical School, University of East Anglia, Norwich, NR4 7TJ, UK.|Department of Gastroenterology, Norfolk and Norwich University Hospital NHS Trust, Colney Lane, Norwich, NR4 7UY, UK.
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Hart
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands.|Department for Determinants of Chronic Diseases, National Institute for Public Health and the Environment (RIVM), P.O. Box 1, 3720 BA, Bilthoven, The Netherlands.|Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK.|Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Jalan Universiti, 50603, Kuala Lumpur, Malaysia.
authors.forename: H Bas
authors.initials: HB
authors.lastname: Bueno-de-Mesquita
authors.affiliation: Department of Gastroenterology and Hepatology, University Medical Center Utrecht, P.O. Box 85500, 3508 GA, Utrecht, The Netherlands. boldenbu@umcutrecht.nl.
authors.forename: Bas
authors.initials: B
authors.lastname: Oldenburg
mesh_terms: D000328:Adult; D000397:Air Pollution / Q000706:statistics & numerical data*; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000453:epidemiology*; D003424:Crohn Disease / Q000453:epidemiology*; D003718:Denmark / Q000453:epidemiology; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D005060:Europe / Q000453:epidemiology; D005260:Female; D005602:France / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D015212:Inflammatory Bowel Diseases / Q000453:epidemiology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009426:Netherlands / Q000453:epidemiology; D016017:Odds Ratio; D052638:Particulate Matter; D006113:United Kingdom / Q000453:epidemiology; D001335:Vehicle Emissions
chemical_list: D052638:Particulate Matter; D001335:Vehicle Emissions
keywords: Air pollution; Crohn’s disease; Inflammatory bowel disease; Particulate matter; Ulcerative colitis