Table 2.
Linear mixed-effects model for the association of gum treatment and cognitive decline (N = 866)
| Model 1 | Model 2 | Model 3 | Model 4 | |
|---|---|---|---|---|
| β coefficient (95% confidence intervals) | ||||
| Have gum treatment (ref. no) | 0.260 (−0.364, 0.883) | 0.082 (−0.465, 0.629) | 0.094 (−0.449, 0.637) | −0.270 (−1.060, 0.520) |
| Time | −0.324 (−0.481, –1.669)*** | −0.349 (−0.454, −0.243)*** | −0.361 (−0.465, –0.257)*** | −0.499 (−0.669, –0.331)*** |
| Gum treatment × time | 0.041 (0.021, 0.061)*** | 0.039 (0.015, 0.0063)*** | 0.030 (0.007, 0.053)** | 0.025 (0.005, 0.044)* |
| Age, years | −0.145 (−0.158, –0.133)*** | −0.152 (−0.166, –0.138)*** | −0.169 (−0.192, –0.146)*** | |
| Women (ref. men) | 0.776 (0.532, 1.019)*** | 0.910 (0.661, 1.158)*** | 0.514 (0.125, 0.903)** | |
| Race (ref. white) | ||||
| Black | −2.105 (−2.542, −1.669)*** | −2.068 (−2.508, −1.628)*** | −2.724 (−3.623, −1.824)*** | |
| Other | −0.786 (−1.341, −0.231)** | −0.789 (−1.341, −0.237)** | −0.772 (−1.405, −0.139)* | |
| Ethnicity (ref. other) | ||||
| Hispanic | −0.887 (−1.364, −0.410)*** | −0.916 (−1.389, −0.442)*** | −0.848 (−1.639, −0.569)* | |
| Education (years of schooling) | 0.387 (0.340, 0.433)*** | 0.371 (0.325, 0.417)*** | 0.374 (0.301, 0.446)*** | |
| Annual household income (per $1,000) | 0.002 (0.001, 0.002)*** | 0.002 (0.001, 0.002)*** | 0.002 (0.001, 0.002)*** | |
| Current smoker (ref. no) | −1.351 (−1.765, −0.936)*** | −1.390 (−2.019, −0.761)*** | ||
| Socially isolated (ref. not) | −0.229 (−0.515, 0.057) | 0.216 (−0.220, 0.651) | ||
| Obesity (ref. no) | 0.017 (−0.252, 0.287) | −0.244 (−0.675, 0.186) | ||
| Depressive symptoms | −0.235 (−0.305, −0.166)*** | −0.295 (−0.396, −0.193)*** | ||
| Having hypertension (ref. no) | 0.141 (−0.106, 0.389) | 0.009 (−0.372, 0.391) | ||
| Having diabetes (ref. no) | −0.406 (−0.722, −0.089)** | −0.823 (−1.325, −0.321)*** | ||
| Disability in ADL (ref. no) | −0.311 (−0.930, 0.307) | 0.524 (−0.296, 1.345) | ||
| Periodontal symptoms | −0.026 (−0.051, −0.002) | −0.024 (−0.050, 0.002) | ||
| Covered by dental insurance (ref. not) | 1.267 (0.487, 2.048)*** | |||
Model 1: gum treatment only. Model 2: adjustment for age, sex, race, ethnicity, education, income. Model 3: further adjusted for smoking, social isolation, hypertension, diabetes, disability in ADL, and periodontal symptoms. Model 4 was further adjusted for dental insurance coverage.
ADL, activities of daily living.
Statistical significance is shown as *p < 0.05; **p < 0.01; ***p < 0.001.