title: Involvement of interleukin-1 genotypes in the association of coronary heart disease with periodontitis.
abstract: BACKGROUND
  Epidemiologic studies demonstrated an association between periodontitis (PE) and coronary heart disease (CHD). The coexistence of the two disease entities could be dependent on mutual risk factors, and polymorphism of the interleukin (IL)-1 gene cluster associated with the severity of PE might also be involved in the pathogenesis of CHD.
  
  
  METHODS
  The study consisted of 225 dentate white subjects, including 97 patients with CHD and 128 controls. Patients with confirmed diagnoses of CHD were recruited after being discharged from a cardiology department, and controls without CHD were recruited consecutively from the Copenhagen City Heart Study. Mean alveolar bone level (ABL) was measured on radiographs. ABL was stratified into ABL1 (ABL < or = 2 mm), ABL2 (2 mm <ABL < or = 4 mm), and ABL3 (ABL >4 mm). Genotypes were analyzed by amplifying the polymorphic regions of the IL-1 gene cluster using polymerase chain reaction, followed by restriction digestion and gel electrophoresis.
  
  
  RESULTS
  In the univariate analysis, allele 2 of IL-1B+3954 and IL-1B-511 was associated with ABL (P = 0.040 and P = 0.039, respectively), whereas no association was found with allele 2 of IL-1A+4845 or IL-1RN variable number tandem repeat (VNTR) (P = 0.445 and P = 0.375, respectively). A lower ABL was associated with the occurrence of allele 2 of IL-1B-511. The multiple logistic regression analysis also showed a significant association of allele 1 of IL-1B-511 with high ABL (P = 0.049) and of allele 2 of IL-1A+4845 with high ABL among individuals with CHD (P = 0.050). There was no association between any of the polymorphisms of IL-1 and CHD in the univariate or multiple analyses. However, in a binary multiple logistic regression model, carriage of allele 1 of IL-1RN VNTR was found to be associated with the occurrence of both CHD and ABL3 (P = 0.016).
  
  
  CONCLUSIONS
  Allele 1 of IL-1RN VNTR may be associated with the coexistence of CHD and PE in a multiple regression model.
authors.affiliation: Department of Periodontology, Dental School, University of Copenhagen, Copenhagen, Denmark. kge@sst.dk
authors.forename: Karen
authors.initials: K
authors.lastname: Geismar
authors.forename: Christian
authors.initials: C
authors.lastname: Enevold
authors.forename: Lars Korsbaek
authors.initials: LK
authors.lastname: Sørensen
authors.forename: Finn
authors.initials: F
authors.lastname: Gyntelberg
authors.forename: Klaus
authors.initials: K
authors.lastname: Bendtzen
authors.forename: Bjarne
authors.initials: B
authors.lastname: Sigurd
authors.forename: Palle
authors.initials: P
authors.lastname: Holmstrup
mesh_terms: D000483:Alleles; D016301:Alveolar Bone Loss / Q000145:classification / Q000150:complications; D016022:Case-Control Studies; D003327:Coronary Disease / Q000150:complications / Q000276:immunology*; D048909:Diabetes Complications; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D005838:Genotype; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein / Q000235:genetics; D007375:Interleukin-1 / Q000235:genetics*; D053582:Interleukin-1alpha / Q000235:genetics; D053583:Interleukin-1beta / Q000235:genetics; D008297:Male; D008875:Middle Aged; D018598:Minisatellite Repeats / Q000235:genetics; D010518:Periodontitis / Q000150:complications / Q000276:immunology*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012307:Risk Factors; D012907:Smoking; D016388:Tooth Loss / Q000150:complications
chemical_list: D053590:Interleukin 1 Receptor Antagonist Protein; D007375:Interleukin-1; D053582:Interleukin-1alpha; D053583:Interleukin-1beta