title: Serum C-reactive protein and immunoglobulin G antibodies to periodontal pathogens may be effect modifiers of periodontitis and hyperglycemia.
abstract: BACKGROUND
  Serum C-reactive protein (CRP) is elevated in both periodontitis and type 2 diabetes mellitus through inflammation. Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis have been found in periodontal pockets in patients with diabetes. This study examines effect modification by examining the extent to which the associations between periodontitis and hyperglycemia were different by levels of serum CRP and periodontal pathogens.
  
  
  METHODS
  Blood samples with plasma were evaluated for immunoglobulin G antibodies, CRP, and fasting glucose from 5,731 participants ≥ 20 years old receiving oral examinations and providing other health-related data from the National Health and Nutrition Examination Survey III. The study participants were classified into quartiles of probing depth (PD) and clinical attachment level (CAL). The first quartile was the reference. Logistic regression models with survey procedures were used to explore the roles of inflammation levels from serum CRP and periodontal pathogens on the relations with periodontitis, including PD, CAL, and hyperglycemia, and their joint associations with interaction terms.
  
  
  RESULTS
  Stronger associations between PD and diabetes existed in people having elevated CRP and titers for P. gingivalis; odds ratios comparing extreme quartiles of PD were 1.31 and 3.40 in the groups with low and high CRP, respectively, and 1.28 and 2.96 in groups with low and high titers for P. gingivalis, respectively. The joint association patterns were similar for CAL and diabetes.
  
  
  CONCLUSIONS
  The strengths of association between periodontitis and diabetes were stronger in people having elevated serum CRP and P. gingivalis titers. This may suggest that chronic inflammatory conditions could increase the impact of periodontitis on hyperglycemic status.
authors.affiliation: Department of Preventive Dentistry, School of Dentistry, Kyungpook National University, Daegu, South Korea.
authors.forename: Youn-Hee
authors.initials: YH
authors.lastname: Choi
authors.forename: Robert E
authors.initials: RE
authors.lastname: McKeown
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Mayer-Davis
authors.forename: Angela D
authors.initials: AD
authors.lastname: Liese
authors.forename: Keun-Bae
authors.initials: KB
authors.lastname: Song
authors.forename: Anwar T
authors.initials: AT
authors.lastname: Merchant
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D016976:Aggregatibacter actinomycetemcomitans / Q000276:immunology*; D000907:Antibodies, Bacterial / Q000097:blood*; D001786:Blood Glucose / Q000032:analysis; D002097:C-Reactive Protein / Q000032:analysis*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000276:immunology / Q000382:microbiology; D004522:Educational Status; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000097:blood / Q000276:immunology / Q000382:microbiology*; D007074:Immunoglobulin G / Q000097:blood*; D007182:Income; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications; D017622:Periodontal Attachment Loss / Q000276:immunology / Q000382:microbiology; D010514:Periodontal Pocket / Q000276:immunology / Q000382:microbiology; D010518:Periodontitis / Q000097:blood / Q000276:immunology / Q000382:microbiology*; D016966:Porphyromonas gingivalis / Q000276:immunology*; D011236:Prediabetic State / Q000097:blood / Q000276:immunology / Q000382:microbiology; D012737:Sex Factors; D016388:Tooth Loss / Q000150:complications; D055815:Young Adult
chemical_list: D000907:Antibodies, Bacterial; D001786:Blood Glucose; D007074:Immunoglobulin G; D002097:C-Reactive Protein
keywords: Aggregatibacter actinomycetemcomitans; Porphyromonas gingivalis; diabetes mellitus; inflammation; periodontitis; prediabetic state