Association between weight-adjusted waist index and severe periodontitis using NHANES 2009-2014

The Weight-adjusted Waist Index (WWI) is a novel anthropometric indicator for assessing obesity. Given the well-established association between obesity and periodontitis, this cross-sectional clinical study aimed to investigate the relationship between WWI and severe periodontitis while evaluating its potential as a simple predictive marker for periodontitis. The study analyzed periodontal examination data and WWI measurements from participants in the 2009-2014 National Health and Nutrition Examination Survey (NHANES), employing weighted logistic regression, smoothed curve fitting, and subgroup analyses. Among the 10,307 eligible participants, results demonstrated a significant positive correlation between WWI and the prevalence of stage III/IV periodontitis. After comprehensive adjustment for all confounding factors, each 1-unit increase in WWI was associated with a 1.19-fold higher risk of stage III/IV periodontitis (OR = 1.19, 95% CI 1.06-1.32, P = 0.007977). Subgroup analysis revealed that this association showed statistically significant variation only in the hypertension subgroup, indicating that the WWI-severe periodontitis relationship is particularly applicable to non-hypertensive individuals. These findings confirm that WWI can serve as a novel obesity-based predictive indicator for severe periodontitis.