Frequent tooth brushing may reduce type 2 diabetes risk
A cohort of Korean adults who reported brushing their teeth at least three times per day were less likely to develop type 2 diabetes during 10 years of follow-up compared with those who brushed once daily or less, with the presence of periodontal disease and missing teeth further increasing disease risk, according to findings published in Diabetologia.
“Because periodontal disease is a microbially triggered chronic inflammatory disease, associated systemic inflammatory reactions from the invasion of oral bacteria and release of inflammatory mediators could affect glycemic control,” Tae-Jin Song, MD, PhD, FACS, assistant professor in the department of neurology at Mokdong Hospital at Ewha Womans University College of Medicine in Seoul, South Korea, said in the study background. “It is therefore plausible that systemic and chronic inflammatory reactions derived from periodontal disease or poor oral hygiene may impact the occurrence of new-onset diabetes. Furthermore, paradoxically, transient bacteremia is also caused by regular tooth brushing, even in individuals with good oral health. However, studies regarding the association of periodontal disease and oral hygiene indicators with the occurrence of new-onset diabetes are lacking, particularly in a longitudinal setting.”
Song and colleagues analyzed data collected between 2003 and 2006 from 188,013 adults without diabetes at baseline from the Korean National Health Insurance System database, assessing the prevalence of periodontal disease as defined by at least two claims for treatment of acute periodontitis, chronic periodontitis and periodontosis (mean age, 53 years; 57.9% men; 20.5% current smokers). Oral hygiene behaviors, such as number of tooth brushings, a dental visit for any reason and professional dental cleanings, were collected via self-report. Researchers followed the cohort through 2015 for incident diabetes.
Within the cohort, 17.5% had periodontal disease. According to surveys, 44% of adults visited a dental clinic for any reason, 42.6% of adults reported brushing their teeth at least three times per day, and 1.1% were missing 15 or more teeth.
During median follow-up of 10 years, 31,545 adults developed diabetes, for a 10-year event rate of 16.1% (95% CI, 15.9-16.3). The presence of periodontal disease (P < .001) and number of missing teeth (P < .001) were associated with an increased risk for new-onset diabetes; however, professional dental cleanings and frequent tooth brushing were negatively associated with new-onset diabetes (P < .001 for both).
In a model adjusted for age, demographic factors, comorbidities, oral health and tooth brushing frequency, researchers found that the presence of periodontal disease increased risk for new-onset diabetes compared with those who did not have periodontal disease (HR = 1.09; 95% CI, 1.07-1.12). Additionally, adults who reported brushing teeth at least three times per day were 8% less likely to develop diabetes vs. those who brush once daily or less (HR = 0.92; 95% CI, 0.89-0.95), with results persisting after adjustment.
Compared with adults with no missing teeth, those with at least 15 missing teeth were 21% more likely to develop diabetes during follow-up (HR = 1.21; 95% CI, 1.09-1.33).
“Professional dental cleaning was not significantly associated with the occurrence of new-onset diabetes in the multivariable analysis, even though this oral hygiene indicator was negatively correlated with the occurrence of new-onset diabetes in the univariable analysis,” the researchers wrote.
The researchers noted that poor oral hygiene may be related to the chronic inflammatory process, which affects the supporting structures of the teeth.
“Ulceration in periodontal pockets and teeth loss provide easy access for the translocation of oral bacteria into the systemic circulation, and dysbiosis of the oral biofilm with high virulence leads to indirect induction of proinflammatory cytokines,” the researchers wrote. “The cytokines increase the inflammatory burden both locally and systemically. Moreover, inflammatory biomarkers are elevated in advanced stages of poor oral hygiene because of systemic inflammation.” – by Regina Schaffer
Disclosures: The authors report no relevant financial disclosures.