Table 2. The associations between weight-adjusted waist index and periodontitis.

Exposure	Model 1 [OR (95% CI)]	Model 2 [OR (95% CI)]	Model 3 [OR (95% CI)]
WWI (continuous)	1.48 (1.40, 1.56)	1.38 (1.30, 1.47)	1.20 (1.12, 1.28)
WWI (quartile)
Quartile 1	reference	reference	reference
Quartile 2	1.33 (1.19, 1.48)	1.18 (1.05, 1.33)	1.06 (0.94, 1.21)
Quartile 3	1.65 (1.48, 1.84)	1.36 (1.20, 1.54)	1.13 (0.99, 1.29)
Quartile 4	2.10 (1.88, 2.35)	1.73 (1.51, 1.97)	1.27 (1.10, 1.46)
P for trend	< 0.001	< 0.001	0.001

Model 1: no covariates were adjusted. Model 2: age, gender, and race were adjusted. Model 3: age, gender, race, education level, PIR, smoking, alcohol drinking, diabetes, triglycerides, and high-density lipoprotein cholesterol were adjusted.