A new study suggests severe gum disease - also known as periodontitis - may be an early marker of type 2 diabetes.
In the United States, 29 million people live with the disease. Of these, over 8 million people have it but have not been diagnosed, according to the Centers for Disease Control and Prevention (CDC).
The CDC also estimate that 37 percent of American adults over the age of 20 have prediabetes.
The authors also suggest a simple finger stick diabetes screening procedure could be carried out in the dental office to avoid the adverse effects of leaving diabetes untreated.
Studying the link between severe gum disease and diabetes
Researchers from the University of Amsterdam in The Netherlands assessed a total of 313 participants from a dental clinic at the university.
Of these, 126 patients had mild-to-moderate gum disease, 78 patients had severe periodontitis, and 198 individuals did not have signs of gum disease.
Participants with periodontitis had a higher body mass index (BMI) than the rest, with an average BMI of 27. However, other diabetes risk factors - such as high blood pressure or high cholesterol - were similar across all three groups.
The researchers analyzed higher glycated hemoglobin (HbA1c) values in dry blood spots, and evaluated the differences in mean HbA1c values, as well as the prevalence of diabetes and prediabetes between the two groups.
HbA1c values measure the average level of blood sugar in the last 2-3 months. The dry blood spots were obtained by sampling participants' blood using a finger pin-prick test.
Prediabetes is commonly considered to range between an HbA1C value of 39-47 millimoles per mol (mmol/mol).
Most diabetes cases found among those with periodontitis
The analysis revealed that those with the most severe form of periodontitis also had the highest HbA1c values.
The average HbA1c values for the severe gum disease group was 45 mmol/mol, compared with 43 mmol/mol in those with mild-to-moderate gum disease and 39 mmol/mol among those without gum disease.
Additionally, the researchers found a high percentage of people with suspected diabetes and prediabetes among participants with mild-to-moderate as well as severe gum disease.
In the severe gum disease group, 23 percent of study participants were suspected of diabetes, whereas 14 percent of the mild-to-moderate gum disease participants had suspected diabetes. In the severe gum disease group, 47 percent had prediabetes, and 46 percent of those in the mild-to-moderate group had prediabetes.
By comparison, 37 percent of those with no gum disease had prediabetes, and 10 percent had suspected diabetes.
Additionally, the researchers found previously undiagnosed cases of diabetes across the three groups: 8.5 percent of those with no gum disease and a little under 10 percent of those with mild-to-moderate gum disease had not been previously diagnosed with the disease until the study.
As much as 18 percent of those with severe gum disease had not been diagnosed with diabetes.
The study is observational, so it cannot explain a causal link between gum disease and diabetes. However, the authors suggest that screening patients with severe periodontitis for diabetes as part of dental medical practices might be an effective way of avoiding complications of the disease. The authors conclude:
"[The findings confirm] the assumption that severe periodontitis could be an early sign of undiagnosed diabetes [...] The early diagnosis and intervention of prediabetes prevent the common microvascular and macrovascular complications and are cost-effective."