Impact of periodontitis on diabetic complications

Background + Aims

• Chronic kidney disease (CKD) affects 8–13% of the global population and is linked to higher mortality, primarily from cardiovascular disease (CVD).
• Systemic inflammation is a key non-traditional risk factor in CKD.
• Severe periodontitis, one of the most common diseases, can cause systemic inflammation through ulcerated oral tissues, increasing markers like C-reactive protein and interleukin-6.
• Studies suggest periodontitis may contribute to CVD and worsen CKD outcomes.
• Prior research indicates a higher prevalence of periodontitis in CKD patients, with systematic reviews showing a significant association between the two conditions. Successful periodontal treatment reduces systemic inflammation in both CKD and non-CKD patients. However, existing studies linking periodontitis to mortality in CKD have involved small cohorts with short follow-up periods.
• This study aimed to explore the relationship between periodontitis and mortality (all-cause and CVD) in stage 3–5 CKD patients using large-scale, population-based data, accounting for traditional risk factors like diabetes, hypertension, and smoking.

Materials + Methods

• This study used data from the Third National Health and Nutrition Examination Survey (NHANES III, 1988–1994), a nationally representative survey of the U.S. population.
• Participants underwent interviews and assessments.
• Periodontal health was evaluated through clinical measurements such as probing pocket depth (PPD), clinical attachment loss (CAL), and bleeding on probing (BOP), with periodontitis classified using CDC/AAP criteria. Edentulous participants were included in a separate group.
• CKD was identified using estimated glomerular filtration rate (eGFR) calculated with the CKD-EPI equation. Urinary albumin-to-creatinine ratio (ACR) was used to classify albuminuria. Traditional risk factors such as hypertension, diabetes, smoking, and body mass index (BMI) were assessed alongside demographic and socio-economic data.
• Mortality data were obtained through linkage with the National Death Index, covering deaths up to December 2006. CVD mortality was categorised using International Classification of Diseases (ICD) codes.
• Statistical analyses accounted for the complex survey design and sampling weights to generalise findings to the US population. Cox proportional hazards models assessed the relationship between periodontal status, traditional risk factors, and mortality (all-cause and CVD).
• Interactions between periodontal health and CKD status were evaluated, along with potential modifications by age, gender, and ethnicity.

Results

• The study analysed 13,784 individuals aged 20 years or older from the NHANES III dataset, with a median follow-up of 14.3 years. Among these, 861 individuals (6%) were classified as having chronic kidney disease (CKD).
• Those with CKD were older, had higher rates of diabetes, hypertension, and CVD and were more likely to suffer from periodontitis or be edentulous.
• Periodontitis and CKD were both associated with increased mortality:
  • Individuals with CKD had a 44% higher rate of all-cause mortality.
  • Those with periodontitis had a 36% increased risk. Periodontitis severity correlated with higher mortality rates.
  • The combination of CKD and periodontitis significantly increased 10-year mortality rates, comparable to the risk posed by CKD with diabetes.
• Cardiovascular mortality rates were also elevated in individuals with CKD (60% increased risk) and those with periodontitis (38% increased risk).
• The impact of periodontitis on mortality:
  • Was consistent across CKD and non-CKD populations.
  • Demonstrated continuous periodontal measures showing a dose-dependent relationship with mortality.
  • Showed edentulous individuals under 65 years of age faced higher mortality risks compared to older individuals.
• Traditional risk factors such as diabetes, hypertension, and smoking further increased mortality risk.

Limitations