Dose-response relationship between periodontal inflamed surface area and HbA1c in type 2 diabetics

J Clin Periodontol. 2009 Apr;36(4):295-300. doi: 10.1111/j.1600-051X.2009.01377.x. Epub 2009 Mar 11.


Background: A dose-response relationship between the amount of inflamed periodontal tissue and HbA1c level, might be indicative for a causal association between periodontitis and type 2 diabetes.

Aim: To assess a dose-response relationship between the periodontal inflamed surface area (PISA), as a measure of the amount of inflamed periodontal tissue, and HbA1c levels in type 2 diabetics.

Material and methods: Forty consecutive dentate type 2 diabetics attending their general practitioner for regular check-up, underwent full-mouth probing pocket depth and bleeding on probing assessment. From these data PISA was calculated. HbA1c levels were retrieved from patients' medical files. The dose-response relationship between PISA and HbA1c levels was assessed using multiple linear regression analyses, controlling for factors that might influence PISA or HbA1c levels.

Results: The higher the PISA of type 2 diabetics was, the higher their HbA1c levels were. On a group level, an increase of PISA with 333 mm(2) was associated with a 1.0 percentage point increase of HbA1c, independent of the influence of other factors.

Conclusion: On a group level, there is a dose-response relationship between PISA and HbA1c in type 2 diabetics. This might be an indication of a causal relationship between type 2 diabetes and periodontitis.

MeSH terms

  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes Mellitus, Type 2 / complications*
  • Female
  • Glycated Hemoglobin / analysis*
  • Humans
  • Linear Models
  • Male
  • Middle Aged
  • Overweight / blood
  • Overweight / complications
  • Periodontal Index
  • Periodontitis / blood
  • Periodontitis / complications*
  • Periodontitis / pathology*


  • Glycated Hemoglobin A
  • hemoglobin A1c protein, human