title: The Association of Gum Bleeding with Respiratory Health in a Population Based Study from Northern Europe.
abstract: BACKGROUND
  There is little knowledge about how oral and respiratory health is interrelated even though the mucosa of the oral cavity and airways constitutes a continuum and the exposures to these are partly similar.
  
  
  OBJECTIVE
  To investigate whether gum bleeding is related to asthma, respiratory symptoms and self-reported COPD.
  
  
  METHODS
  A postal questionnaire including questions about respiratory and oral health was sent to general population samples in seven Northern European centres. In 13,409 responders, gum bleeding when brushing teeth was reported always/often by 4% and sometimes by 20%. Logistic regressions accounted for age, smoking, educational level, centre and gender. Effects of BMI, cardio-metabolic diseases, early life factors, gastro-oesophageal reflux, dental hygiene, nasal congestion, and asthma medication were addressed.
  
  
  RESULTS
  Gum bleeding always/often was significantly associated with ≥ 3 asthma symptoms (OR 2.58, 95% CI 2.10-3.18), asthma (1.62 [1.23-2.14]) and self-reported COPD (2.02 [1.28-3.18]). There was a dose-response relationship between respiratory outcomes and gum bleeding frequency (≥ 3 symptoms: gum bleeding sometimes 1.42 [1.25-1.60], often/always 2.58 [2.10-3.18]), and there was no heterogeneity between centres (p(heterogeneity) = 0.49). None of the investigated risk factors explained the associations. The observed associations were significantly stronger among current smokers (p(interaction) = 0.004).
  
  
  CONCLUSIONS
  A consistent link between gum bleeding and obstructive airways disease was observed, not explained by common risk factors or metabolic factors. We speculate that oral pathogens might have unfavourable impact on the airways, and that the direct continuity of the mucosa of the oral cavity and the airways reflects a pathway that might provide novel opportunities for interventions.
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway.|Department of Gynecology and Obstetrics, Haukeland University Hospital, Bergen, Norway.
authors.forename: Francisco
authors.initials: F
authors.lastname: Gómez Real
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Laura
authors.initials: L
authors.lastname: Pérez Barrionuevo
authors.affiliation: Department of Surgical and Perioperative Sciences, Umeå University, Umeå, Sweden.
authors.forename: Karl
authors.initials: K
authors.lastname: Franklin
authors.affiliation: Department of Medical Sciences, Respiratory, Allergy and Sleep Research, Uppsala University, Uppsala, Sweden.
authors.forename: Eva
authors.initials: E
authors.lastname: Lindberg
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway.|Department of Occupational Medicine, Haukeland University Hospital, Bergen, Norway.
authors.forename: Randi Jacobsen
authors.initials: RJ
authors.lastname: Bertelsen
authors.affiliation: University of Iceland, Faculty of Medicine, Reykjavik, Iceland.
authors.forename: Bryndís
authors.initials: B
authors.lastname: Benediktsdóttir
authors.affiliation: Department of Public Health and Clinical Medicine, Umeå University, Umeå, Sweden.
authors.forename: Bertil
authors.initials: B
authors.lastname: Forsberg
authors.affiliation: University of Iceland, Faculty of Medicine, Reykjavik, Iceland.
authors.forename: Thorarinn
authors.initials: T
authors.lastname: Gislason
authors.affiliation: Lung Clinic, Tartu University Clinics, Tartu, Estonia.
authors.forename: Rain
authors.initials: R
authors.lastname: Jögi
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway.|Centre for Clinical Research, Haukeland University Hospital, Bergen, Norway.
authors.forename: Ane
authors.initials: A
authors.lastname: Johannessen
authors.affiliation: Centre for Clinical Research, Haukeland University Hospital, Bergen, Norway.
authors.forename: Ernst
authors.initials: E
authors.lastname: Omenaas
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Eirunn
authors.initials: E
authors.lastname: Saure
authors.affiliation: Department of Public Health, Section for Environment, Occupation and Health, Aarhus University, Aarhus, Denmark.
authors.forename: Vivi
authors.initials: V
authors.lastname: Schlünssen
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: Trude Duelien
authors.initials: TD
authors.lastname: Skorge
authors.affiliation: Department of Occupational and Environmental Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden.
authors.forename: Kjell
authors.initials: K
authors.lastname: Torén
authors.affiliation: Clinica Dental Pérez Saveedra, Málaga, Spain.
authors.forename: Antonio
authors.initials: A
authors.lastname: Pérez Saavedra
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway.|Department of Occupational Medicine, Haukeland University Hospital, Bergen, Norway.
authors.forename: Øistein
authors.initials: Ø
authors.lastname: Svanes
authors.affiliation: Department of Clinical Dentistry, University of Bergen, Bergen Norway.
authors.forename: Anne Nordrehaug
authors.initials: AN
authors.lastname: Åstrøm
authors.affiliation: Department of Medical Sciences, Respiratory, Allergy and Sleep Research, Uppsala University, Uppsala, Sweden.
authors.forename: Christer
authors.initials: C
authors.lastname: Janson
authors.affiliation: Department of Clinical Science, University of Bergen, Bergen, Norway.|Department of Occupational Medicine, Haukeland University Hospital, Bergen, Norway.
authors.forename: Cecilie
authors.initials: C
authors.lastname: Svanes
mesh_terms: D001249:Asthma / Q000150:complications*; D005060:Europe; D005260:Female; D005884:Gingival Hemorrhage / Q000150:complications / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications*