title: Reduced risk of pancreatic cancer associated with asthma and nasal allergies.
abstract: Studies indicate an inverse association between ductal adenocarcinoma of the pancreas (PDAC) and nasal allergies. However, controversial findings are reported for the association with asthma. Understanding PDAC risk factors will help us to implement appropriate strategies to prevent, treat and diagnose this cancer. This study assessed and characterised the association between PDAC and asthma and corroborated existing reports regarding the association between allergies and PDAC risk.
  
  
  
  Information about asthma and allergies was collated from 1297 PDAC cases and 1024 controls included in the PanGenEU case-control study. Associations between PDAC and atopic diseases were studied using multilevel logistic regression analysis. Meta-analyses of association studies on these diseases and PDAC risk were performed applying random-effects model.
  
  
  
  Asthma was associated with lower risk of PDAC (OR 0.64, 95% CI 0.47 to 0.88), particularly long-standing asthma (>=17 years, OR 0.39, 95% CI 0.24 to 0.65). Meta-analysis of 10 case-control studies sustained our results (metaOR 0.73, 95% CI 0.59 to 0.89). Nasal allergies and related symptoms were associated with lower risk of PDAC (OR 0.66, 95% CI 0.52 to 0.83 and OR 0.59, 95% CI 0.46 to 0.77, respectively). These results were supported by a meta-analysis of nasal allergy studies (metaOR 0.6, 95% CI 0.5 to 0.72). Skin allergies were not associated with PDAC risk.
  
  
  
  This study shows a consistent inverse association between PDAC and asthma and nasal allergies, supporting the notion that atopic diseases are associated with reduced cancer risk. These results point to the involvement of immune and/or inflammatory factors that may either foster or restrain pancreas carcinogenesis warranting further research to understand the molecular mechanisms driving this association.
authors.affiliation: Genetic and Molecular Epidemiology Group, Spanish National Cancer Research Center (CNIO), Madrid, Spain.
authors.forename: Paulina
authors.initials: P
authors.lastname: Gomez-Rubio
authors.affiliation: Centre for Research in Environmental Epidemiology (CREAL), Barcelona, Spain.
authors.forename: Jan-Paul
authors.initials: JP
authors.lastname: Zock
authors.affiliation: Genetic and Molecular Epidemiology Group, Spanish National Cancer Research Center (CNIO), Madrid, Spain.
authors.forename: Marta
authors.initials: M
authors.lastname: Rava
authors.affiliation: Genetic and Molecular Epidemiology Group, Spanish National Cancer Research Center (CNIO), Madrid, Spain.
authors.forename: Mirari
authors.initials: M
authors.lastname: Marquez
authors.affiliation: National Cancer Registry Ireland, Cork, Ireland, and Institute of Health & Society, Newcastle University, UK.
authors.forename: Linda
authors.initials: L
authors.lastname: Sharp
authors.affiliation: Hospital Madrid-Norte-Sanchinarro, Madrid, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Hidalgo
authors.affiliation: Department of Oncology, Hospital Ramón y Cajal, Madrid, Spain.
authors.forename: Alfredo
authors.initials: A
authors.lastname: Carrato
authors.affiliation: Hospital del Mar-Parc de Salut Mar, Barcelona, Spain.
authors.forename: Lucas
authors.initials: L
authors.lastname: Ilzarbe
authors.affiliation: Technical University of Munich, Munich, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Michalski
authors.affiliation: Exocrine Pancreas Research Unit, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
authors.forename: Xavier
authors.initials: X
authors.lastname: Molero
authors.affiliation: Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: Antoni
authors.initials: A
authors.lastname: Farré
authors.affiliation: Department of Surgery, 12 de Octubre University Hospital, Madrid, Spain.
authors.forename: José
authors.initials: J
authors.lastname: Perea
authors.affiliation: The Royal Liverpool University Hospital, Liverpool, UK.
authors.forename: William
authors.initials: W
authors.lastname: Greenhalf
authors.affiliation: Centre for Public Health, Queen's University Belfast, Belfast, UK.
authors.forename: Michael
authors.initials: M
authors.lastname: O'Rorke
authors.affiliation: Instituto Universitario de Oncología del Principado de Asturias, Oviedo, Spain.
authors.forename: Adonina
authors.initials: A
authors.lastname: Tardón
authors.affiliation: Department of Gastroenterology, University Hospital Giessen and Marburg, Marburg, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Gress
authors.affiliation: Laboratorio de Genética Molecular, Hospital General Universitario de Elche, Elche, Spain.
authors.forename: Victor
authors.initials: V
authors.lastname: Barberà
authors.affiliation: Centre for Molecular Oncology, Barts Cancer Institute, Queen Mary University of London, London, UK.
authors.forename: Tatjana
authors.initials: T
authors.lastname: Crnogorac-Jurcevic
authors.affiliation: Hospital Clínico Universitario de Santiago de Compostela, Santiago de Compostela, Spain.
authors.forename: Enrique
authors.initials: E
authors.lastname: Domínguez-Muñoz
authors.affiliation: Cirugía General y del Aparato Digestivo, Hospital Universitario de Salamanca, Salamanca, Spain.
authors.forename: Luís
authors.initials: L
authors.lastname: Muñoz-Bellvís
authors.affiliation: Hospital del Mar-Parc de Salut Mar, Barcelona, Spain.
authors.forename: Cristina
authors.initials: C
authors.lastname: Alvarez-Urturi
authors.affiliation: Exocrine Pancreas Research Unit, Hospital Universitari Vall d'Hebron, Barcelona, Spain.
authors.forename: Joaquim
authors.initials: J
authors.lastname: Balcells
authors.affiliation: Instituto Universitario de Oncología del Principado de Asturias, Oviedo, Spain.
authors.forename: Luis
authors.initials: L
authors.lastname: Barneo
authors.affiliation: The Royal Liverpool University Hospital, Liverpool, UK.
authors.forename: Eithne
authors.initials: E
authors.lastname: Costello
authors.affiliation: Department of Oncology, Hospital Ramón y Cajal, Madrid, Spain.
authors.forename: Carmen
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authors.lastname: Guillén-Ponce
authors.affiliation: Technical University of Munich, Munich, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Kleeff
authors.affiliation: Technical University of Munich, Munich, Germany.
authors.forename: Bo
authors.initials: B
authors.lastname: Kong
authors.affiliation: Department of Pathology and Diagnostics, University of Verona, Verona, Italy.
authors.forename: Rita
authors.initials: R
authors.lastname: Lawlor
authors.affiliation: Gastrocentrum, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Matthias
authors.initials: M
authors.lastname: Löhr
authors.affiliation: Hospital de la Santa Creu i Sant Pau, Barcelona, Spain.
authors.forename: Josefina
authors.initials: J
authors.lastname: Mora
authors.affiliation: Centre for Public Health, Queen's University Belfast, Belfast, UK.
authors.forename: Lim
authors.initials: L
authors.lastname: Murray
authors.affiliation: National Cancer Registry Ireland, Cork, Ireland, and Institute of Health & Society, Newcastle University, UK.
authors.forename: Damian
authors.initials: D
authors.lastname: O'Driscoll
authors.affiliation: Department of Surgery, 12 de Octubre University Hospital, Madrid, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Peláez
authors.affiliation: Hospital del Mar-Parc de Salut Mar, Barcelona, Spain.
authors.forename: Ignasi
authors.initials: I
authors.lastname: Poves
authors.affiliation: Department of Pathology and Diagnostics, University of Verona, Verona, Italy.
authors.forename: Aldo
authors.initials: A
authors.lastname: Scarpa
authors.affiliation: Epithelial Carcinogenesis Group, Spanish National Cancer Research Centre (CNIO), Madrid, Spain.
authors.forename: Francisco X
authors.initials: FX
authors.lastname: Real
authors.affiliation: Genetic and Molecular Epidemiology Group, Spanish National Cancer Research Center (CNIO), Madrid, Spain.
authors.forename: Núria
authors.initials: N
authors.lastname: Malats
mesh_terms: D000368:Aged; D001249:Asthma / Q000453:epidemiology*; D021441:Carcinoma, Pancreatic Ductal / Q000453:epidemiology*; D016022:Case-Control Studies; D017449:Dermatitis, Allergic Contact / Q000453:epidemiology; D005060:Europe / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010190:Pancreatic Neoplasms / Q000453:epidemiology*; D065840:Protective Factors; D065631:Rhinitis, Allergic / Q000453:epidemiology*