Treating gum disease lowers HbA1c in type 2 diabetes patients

Patients with type 2 diabetes who were given 6 months of thorough periodontal treatment lowered their glycated hemoglobin (HbA1c) levels by 0.5%, according to results of a recent study published in the Journal of Clinical Periodontology.

“The main conclusion of the study is that the nonsurgical treatment of periodontitis improves the glycemic status and levels of glycated hemoglobin, and therefore proves the great importance of oral health in these patients,” said co-lead author José López-López, DDS, MD, PhD, professor, Department of Dentistry, University of Barcelona Dental School, Barcelona, Spain.

Researchers have known for some time that type 2 diabetes is a risk factor for gum disease—as glycemic control declines, risk for periodontitis goes up. But what hasn’t been proven is whether careful periodontal treatment in diabetic patients can improve metabolic control.

For this study, Dr. López-López and colleagues recruited 90 patients who had both type 2 diabetes and chronic periodontitis. At baseline, all patients received oral hygiene instruction as well as removal of supragingival plaque and calculus. Half of patients were randomly assigned to a treatment group in which they received full-mouth debridement (scaling and root planing) at baseline and as needed. The other patients were randomly assigned to a control group with no additional dental treatment.

HbA1c reduction

After 6 months, patients in the treatment group showed improvements in periodontal health as well as significant changes in plaque index and gingival index values. Those in the control group showed almost no improvement.

In addition, fasting plasma glucose scores decreased significantly in the treatment group but increased in the control group. Sensitivity analysis confirmed greater improvement in HbA1c levels among patients in the treatment group (−0.51%) than in the control group (−0.06%).

“Although modest, the difference (in HbA1c level) is of significant clinical impact, because any reduction in glycosylated hemoglobin is associated with a decrease in the long-term complications,” the authors wrote.

“In fact, 1% reduction in HbA1c is associated with a 21% reduction in the number of deaths related to diabetes, a 14% reduction in myocardial infarction, and a 37% reduction in the microvascular complications,” they noted. “This highlights the importance of periodontal treatment in patients with diabetes, as it will contribute to HbA1c control and therefore to a reduction in complications.”

The other way ‘round

“In this new study, we saw that there is not only a relation between (patients) going from diabetes to periodontal diseases, but the other way ‘round, from the periodontal disease to diabetes,” said co-lead author Miquel Viñas, PhD, professor of microbiology, University of Barcelona.

How are periodontal disease and diabetes inter-related? Another recent article in the Journal of Clinical Periodontology noted that people who have both type 2 diabetes and periodontitis have reduced beta-cell function, elevated oxidative stress, and dyslipidemia compared with people with diabetes alone.

“Most studies demonstrate that circulating proinflammatory mediators are elevated in people with diabetes and periodontitis, particularly TNF (tumor necrosis factor)-α, CRP (C-reactive protein), and mediators of oxidative stress,” the authors wrote. “These proinflammatory mediators may affect the control of diabetes.” However, further research is needed to answer this question.

In the meantime, the authors recommend that clinicians provide oral health education and treatment to all patients with diabetes.

“Irrespective of the level of diabetes control, nonsurgical periodontal therapy should be provided, as this may help to improve glycemic control,” they advised.