Association between conicity index and prevalence of periodontitis in US adults: the 2009–2014 NHANES cross-sectional study

• Published in: Scientific reports Vol. 15; no. 1; pp. 21244 - 11
• Main Authors: Xu, Jie, Cui, Jiaming, Xiong, Jingwen, Jiang, Xiatian, Chen, Meng, Luo, Xiaobing
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01.07.2025; Nature Portfolio
• Subjects: 692/499; 692/699; 692/699/3020/3029; 692/700/1538; Adult; Aged; Body Mass Index; Conicity index; Cross-Sectional Studies; Cross-sectional study; Female; Humanities and Social Sciences; Humans; Male; Middle Aged; multidisciplinary; NHANES; Nutrition Surveys; Obesity; Periodontitis; Periodontitis - epidemiology; Prevalence; Risk Factors; ROC Curve; Science; Science (multidisciplinary); United States - epidemiology; Waist Circumference; United States; Obesity; Conicity index; NHANES; Cross-sectional study; Periodontitis
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-025-04359-9

This study investigated the relationship between periodontitis and the Conicity Index (C-index) in the United States. The National Health and Nutrition Examination Survey (NHANES), conducted from 2009 to 2014, found that 5233 out of 10,327 respondents aged 30 years or older had periodontitis. After adjusting for all confounding variables, the likelihood of periodontitis prevalence increased by 13% for every unit rise in the C-index (OR 1.13, 95% CI 1.05, 1.21). A three-category sensitivity analysis of the C-index revealed that the highest group had a 24% greater prevalence of periodontitis compared to the lowest group (OR 1.24, 95% CI 1.07, 1.43). There was no gender difference in the linear and positive correlation between the C-index and the prevalence of periodontitis. Subgroup analyses demonstrated no significant interactions in most subgroups. Additionally, sensitivity analyses that adjusted for missing covariates and physical activity further validated the robustness of the results, confirming that the C-index is independently associated with periodontitis prevalence. Finally, Receiver Operating Characteristic (ROC) analysis indicated that the C-index outperformed Body Mass Index (BMI) and Waist Circumference (WC) in predicting periodontitis, suggesting its potential for early screening. Overall, the C-index, as an indicator of abdominal obesity, reflects not only generalized obesity but is also independently associated with periodontitis prevalence, providing a new and potentially valuable tool for early screening. Notably, the predictive ability of the C-index for periodontitis was significantly superior to that of traditional BMI and WC, indicating higher sensitivity in the early diagnosis and assessment of periodontitis. The clinical application of the C-index can assist healthcare professionals in identifying high-risk individuals at an early stage, enabling timely interventions that may reduce the incidence of periodontitis and subsequent oral health issues.