title: The association between periodontitis and obstructive sleep apnea: a preliminary study.
abstract: OBJECTIVE
  Periodontitis is becoming a highly prevalent disease worldwide. Obstructive sleep apnea (OSA) is a common disorder that is characterized by repeated disruptions in breathing during sleep, and mouth breathing is a common characteristic among patients with OSA. We aimed to assess the hypothesis that OSA is associated with the onset and progression of periodontal disease.
  
  
  METHODS
  This is a cross-sectional study of a total of 687 participants (460 men and 227 women), 47-77 years of age, who were examined between August 2009 and September 2010 as part of the Korean Genome and Epidemiology Study. The participants underwent standard polysomnography, clinical periodontal examination and health-screening examinations. Periodontitis was defined as clinical attachment level (CAL) ≥ 6 mm and probing pocket depth ≥ 4 mm. OSA was determined using the apnea-hypopnea index (AHI), and an AHI score of ≥ 5 was the cut-off used to indicate the presence of OSA.
  
  
  RESULTS
  The results showed that 17.5% of the participants had periodontitis, 46.6% had OSA and 60.0% who were diagnosed with periodontitis had OSA. In our study, old age, male gender, current smoking status, mouth breathing during sleep and high AHI were identified as risk factors for periodontitis. OSA was positively associated with periodontitis [odds ratio (OR) = 1.84, 95% confidence interval (CI) = 1.18-2.87], probing pocket depth (OR = 2.22, 95% CI = 1.30-3.77) and CAL (OR = 1.86, 95% CI = 1.07-3.21) in a dose-response manner. Additionally, OSA was positively associated with periodontitis (OR = 2.51, 95% CI = 1.37-4.62) in subjects ≥ 55 years of age, but not in subjects < 55 years of age.
  
  
  CONCLUSIONS
  There is a significant association between OSA and periodontal disease. Further research is needed to clarify the causal relationship between the two conditions.
authors.affiliation: Department of Pediatrics, Korea University Ansan Hospital, Korea University College of Medicine, Ansan, Korea.
authors.forename: W H
authors.initials: WH
authors.lastname: Seo
authors.forename: E R
authors.initials: ER
authors.lastname: Cho
authors.forename: R J
authors.initials: RJ
authors.lastname: Thomas
authors.forename: S-Y
authors.initials: SY
authors.lastname: An
authors.forename: J J
authors.initials: JJ
authors.lastname: Ryu
authors.forename: H
authors.initials: H
authors.lastname: Kim
authors.forename: C
authors.initials: C
authors.lastname: Shin
mesh_terms: D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009058:Mouth Breathing / Q000453:epidemiology; D017622:Periodontal Attachment Loss / Q000453:epidemiology; D010514:Periodontal Pocket / Q000453:epidemiology; D010518:Periodontitis / Q000453:epidemiology*; D017286:Polysomnography; D011159:Population Surveillance; D011446:Prospective Studies; D056910:Republic of Korea / Q000453:epidemiology; D012307:Risk Factors; D012737:Sex Factors; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology*; D012907:Smoking