title: Risk factors for incident asthma and COPD in a cohort of young adults.
abstract: BACKGROUND
  The aim of the study was to describe potential shared risk factors for incident asthma and COPD in a population-based, 9-year follow-up study.
  
  
  METHODS
  From a cohort of 1191 individuals, aged 20-44, who participated in baseline survey including spirometry, bronchial challenge, and skin prick test (SPT) 742 subjects (62%) were reexamined at follow-up in 2012-2014.
  
  
  RESULTS
  A total of 27 incident cases of asthma and 22 cases of COPD were identified at follow-up corresponding to an incidence rate of 5.8 (95% CI 3.9-8.4) and 3.5 (2.2-5.3) per 1000 person years, respectively. Among the identified COPD cases a total of 12 were Asthma-COPD Overlap Syndrome (ACOS). Atopy defined by positive SPT was a risk factor for asthma in males (OR 7.54; 95% CI 1.24-45.90), whereas risk factors in females were nasal allergy (3.81; 1.20-12.11), FEV1<100% predicted (3.96; 1.07-14.62) and parental asthma (3.06; 1.00-9.40). Risk factors for COPD in males were bronchial hyperresponsiveness (23.13; 1.41-380.50) and FEV1<100% predicted (all male cases had FEV1<100% predicted) and in females current smoking (3.34; 1.16-9.59) and asthma at baseline (5.21; 1.48-18.34).
  
  
  CONCLUSIONS
  No shared risk factors for incident asthma and COPD were found. Despite low power when stratifying by sex risk factors for incident asthma and COPD emphasize considerable gender differences.
authors.affiliation: Department of Occupational Medicine, Hospital of South West Jutland, Esbjerg, Denmark.|Faculty of Health Sciences, Institute of Regional Health Services Research, University of Southern Denmark, Odense, Denmark.
authors.forename: Lisbet Krogh
authors.identifier: http://orcid.org/0000-0002-7068-1257
authors.initials: LK
authors.lastname: Traulsen
authors.affiliation: Department of Occupational and Environmental Medicine, Odense University Hospital, Odense, Denmark.|Research Unit of General Practice, Department of Public Health, University of Southern Denmark, Odense, Denmark.
authors.forename: Jesper
authors.initials: J
authors.lastname: Baelum
authors.affiliation: Department of Clinical Sciences, Center for Primary Health Care Research, Lund University, Malmö, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Halling
authors.affiliation: Department of Occupational Medicine, Hospital of South West Jutland, Esbjerg, Denmark.
authors.forename: Gert
authors.initials: G
authors.lastname: Thomsen
authors.affiliation: Research Unit of General Practice, Department of Public Health, University of Southern Denmark, Odense, Denmark.|Research Unit for Occupational and Environmental Medicine, Institute of Clinical Research, University of Southern Denmark, Odense, Denmark.
authors.forename: Trine
authors.initials: T
authors.lastname: Thilsing
authors.affiliation: Department of Occupational and Environmental Medicine, Odense University Hospital, Odense, Denmark.|Department of Respiratory Medicine, Odense University Hospital, Odense, Denmark.
authors.forename: David
authors.initials: D
authors.lastname: Sherson
authors.affiliation: Department of Public Health, Danish Ramazzini Centre, University of Aarhus, Aarhus, Denmark.
authors.forename: Torben
authors.initials: T
authors.lastname: Sigsgaard
authors.affiliation: Department of Occupational Medicine, Danish Ramazzini Centre, Aalborg University Hospital, Aalborg, Denmark.
authors.forename: Øyvind
authors.initials: Ø
authors.lastname: Omland
authors.affiliation: Department of Occupational Medicine, Danish Ramazzini Centre, Aalborg University Hospital, Aalborg, Denmark.
authors.forename: Tine
authors.initials: T
authors.lastname: Malling
authors.affiliation: Department of Occupational Medicine, Hospital of South West Jutland, Esbjerg, Denmark.|Faculty of Health Sciences, Institute of Regional Health Services Research, University of Southern Denmark, Odense, Denmark.
authors.forename: Lars Rauff
authors.initials: LR
authors.lastname: Skadhauge
mesh_terms: D000328:Adult; D001249:Asthma / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D015897:Comorbidity / Q000639:trends; D003718:Denmark / Q000453:epidemiology; D005260:Female; D005500:Follow-Up Studies; D005541:Forced Expiratory Volume; D006801:Humans; D015994:Incidence; D008297:Male; D011159:Population Surveillance / Q000379:methods*; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D012882:Skin Tests; D013147:Spirometry; D013997:Time Factors; D014797:Vital Capacity; D055815:Young Adult
keywords: COPD; adult; asthma; cohort study; epidemiology; risk factor