**Background:** Periodontitis affects approximately 1.1 billion people worldwide, with 46% of US adults aged 30+ having periodontitis and 8.9% having severe periodontitis. Periodontitis is known to increase risk of cardiovascular disease, diabetes, and chronic kidney disease through inflammatory mechanisms. Abdominal aortic calcification (AAC) is an early marker of atherosclerotic disease and predicts cardiovascular events and mortality. Previous studies have suggested links between periodontitis and arterial calcification at multiple sites, but evidence regarding AAC specifically in a nationally representative US sample was lacking.
**Methods:** This cross-sectional study analyzed data from 2,149 participants aged ≥40 years from the NHANES 2013–2014 cycle who had complete periodontal examinations and DXA scans for AAC assessment. Participants with cancer were excluded. Periodontitis was classified using CDC/AAP definitions (no, mild–moderate, severe periodontitis). AAC was assessed using two semiquantitative scoring tools: AAC-8 (score ≥3 considered high risk) and AAC-24 (score >6 defined as severe calcification). Covariates included socioeconomic factors, smoking, alcohol, BMI, cardiovascular disease, hypertension, diabetes, CKD, and laboratory measurements (albumin, calcium, phosphorus, vitamin D, lipids). Missing data were imputed using the MissForest algorithm. Linear regression and multivariate logistic regression were performed with survey weights, with three levels of adjustment (Model 1: age, sex, race; Model 2: + socioeconomic and health covariates; Model 3: + laboratory measurements). Subgroup analyses and sensitivity analyses were conducted.
**Key Results:** The prevalence of severe periodontitis was 6.77% (95% CI 5.40–8.13) and mild–moderate periodontitis was 29.93% (95% CI 25.36–34.51). The prevalence of severe periodontitis combined with severe AAC was 8.49–8.54%. In fully adjusted logistic regression (Model 3), severe periodontitis was significantly associated with severe AAC by AAC-8 score ≥3 (OR 2.53; 95% CI 1.04–6.17; p=0.043) and by AAC-24 score >6 (OR 3.60; 95% CI 1.48–8.78; p=0.008). Mild–moderate periodontitis was associated with severe AAC only when using the AAC-24 score (OR 2.25; 95% CI 1.24–4.06; p=0.011). When comparing severe AAC versus mild–moderate AAC, both mild–moderate (OR 2.28; 95% CI 1.28–4.06; p=0.008) and severe periodontitis (OR 2.93; 95% CI 1.28–6.69; p=0.014) remained significant. Linear regression showed no significant association after full adjustment. Subgroup analyses found no significant multiplicative interactions by age, sex, CVD, hypertension, diabetes, or CKD (all p for interaction >0.05). Sensitivity analyses excluding participants with missing covariates attenuated some associations, while excluding mild periodontitis or CVD yielded results similar to the main analysis.
**Clinical Implications:** This study provides the first population-based evidence from a nationally representative US sample linking periodontitis to severe AAC. The findings suggest that periodontal health may be a modifiable risk factor for vascular calcification, with implications for cardiovascular risk assessment and prevention. The association persisted after extensive adjustment for confounders, supporting an independent relationship. However, the cross-sectional design precludes causal inference, and the attenuated results in sensitivity analyses warrant cautious interpretation. The authors recommend large-scale prospective studies to confirm these findings and clarify underlying mechanisms, which may involve Porphyromonas gingivalis infection, systemic inflammation, and pathways such as osteoprotegerin/RANKL activation and endoplasmic reticulum stress-induced apoptosis.