Periodontal Disease Effects on Diabetes

The presence of periodontal disease indicates an increased risk of worsening glycemic control over time.49 Furthermore, subjects with both diabetes and periodontitis have shown to have higher rates of complications and higher mortality rates than diabetic subjects without periodontitis.50,51 There is a biologic rationale that could explain an influence of periodontal disease on diabetic status. Periodontitis patients have been shown to have an increase in serum pro-inflammatory markers when compared to subjects without periodontitis; these include including C-reactive protein (CRP), IL-6, and fibrinogen.52-54 Furthermore, patients with periodontitis have also been shown to experience high levels of bacteria and endotoxins entering the bloodstream through seemingly harmless activities such as chewing.55 This dissemination of bacteria associated with periodontitis may play a role in the influence of periodontal disease on diabetes mellitus. Acute bacterial and viral infections have been shown to increase insulin resistance in non-diabetic patients56,57 and chronic gram negative periodontal infections may also result in increased insulin resistance and worsening glycemic control.58

However, there is a controversy about how to interpret this information. The questions remains whether there is an underlying mechanism that affects both disease processes, or whether one condition will actually cause the other to worsen. In non-diabetic patients, severe chronic periodontitis was associated with a 5-fold greater increase in HbA1c over the 5 year study period compared to subjects without diabetes, indicating periodontitis might play a role in increasing hyperglycemia that could potentially increase the risk of developing diabetes.59 However, in a prospective study patients with moderate to severe periodontitis demonstrated an increased risk of developing diabetes, but the association was not significant after adjusting for common risk factors such as smoking, sex, BMI, hypertensive status, and lipid profiles.60 A systematic review of the best data available found relatively weak evidence supporting adverse effects of periodontal disease upon glycemic control in diabetic patients. The authors did caution that better and longer term studies are needed to confirm the significance of this cause and effect relationship.61