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Objective
This study aims to examine the association between the Weight-adjusted Waist Circumference Index (WWI) and the prevalence of periodontitis, providing novel evidence on the link between central obesity and periodontal health.
Methods
A cross-sectional study was conducted with 10,289 participants enrolled from NHANES 2009 to 2014. WWI was calculated by dividing waist circumference by the square root of weight. We employed a multivariate logistic regression model and smoothed curve fitting method to evaluate the relationship between WWI and periodontitis. We also compared different subgroups and analyzed the interaction effects.
Results
A significant positive association between WWI and periodontitis was observed in 10,289 participants aged ≥30 (OR: 1.20, 95% CI: 1.12–1.28). Upon categorizing WWI into quartiles, the top quartile group exhibited a 27% increased prevalence of periodontitis compared to the bottom quartile (OR: 1.27, 95% CI: 1.10–1.46; P for trend = 0.001). Among individuals aged 30 to 60, the strength of this positive correlation is more pronounced than in those aged 60 and above.
Conclusions
WWI demonstrates a positive correlation with periodontitis with a particularly pronounced impact on moderate periodontitis, suggesting its potential to improve periodontitis prevention in a broad population.