Table 4.
Odds ratios (ORs) and 95% confidence intervals (CIs) for periodontal disease by quintiles of soy protein and isoflavone intake in 3956 Japanese females
| Quintile of intake | ||||||
| Variable | 1 | 2 | 3 | 4 | 5 | P for trend |
| Soy protein | ||||||
| Intake, g/day1 | 1.3 | 2.7 | 3.8 | 5.5 | 9.0 | |
| Prevalence | 72/791 (9.1%) | 75/791 (9.5%) | 59/791 (7.5%) | 57/791 (7.2%) | 55/792 (6.9%) | |
| Crude OR (95% CI) | 1.00 | 1.05 (0.75, 1.47) | 0.81 (0.56, 1.15) | 0.78 (0.54, 1.11) | 0.75 (0.52, 1.07) | 0.03 |
| Adjusted OR (95% CI)2 | 1.00 | 1.08 (0.77, 1.53) | 0.85 (0.59, 1.22) | 0.83 (0.58, 1.20) | 0.81 (0.56, 1.17) | 0.10 |
| Isoflavone | ||||||
| Intake, mg/day1 | 7.3 | 15.3 | 21.5 | 31.9 | 52.7 | |
| Prevalence | 79/791 (10.0%) | 68/791 (8.6%) | 61/791 (7.7%) | 56/791 (7.1%) | 54/792 (6.8%) | |
| Crude OR (95% CI) | 1.00 | 0.85 (0.60, 1.19) | 0.75 (0.53, 1.07) | 0.69 (0.48, 0.98) | 0.66 (0.46, 0.94) | 0.01 |
| Adjusted OR (95% CI)2 | 1.00 | 0.86 (0.61, 1.21) | 0.79 (0.55, 1.12) | 0.73 (0.51, 1.04) | 0.71 (0.49, 1.01) | 0.04 |
| Daidzein | ||||||
| Intake, mg/day1 | 2.8 | 5.8 | 8.1 | 12.0 | 19.9 | |
| Prevalence | 77/791 (9.7%) | 69/791 (8.7%) | 62/791 (7.8%) | 56/791 (7.1%) | 54/792 (6.8%) | |
| Crude OR (95% CI) | 1.00 | 0.89 (0.63, 1.25) | 0.79 (0.55, 1.12) | 0.71 (0.49, 1.01) | 0.68 (0.47, 0.97) | 0.01 |
| Adjusted OR (95% CI)2 | 1.00 | 0.90 (0.64, 1.26) | 0.83 (0.58, 1.18) | 0.75 (0.52, 1.08) | 0.73 (0.50, 1.04) | 0.05 |
| Genistein | ||||||
| Intake, mg/day1 | 4.6 | 9.5 | 13.4 | 19.8 | 32.9 | |
| Prevalence | 78/791 (9.9%) | 68/791 (8.6%) | 62/791 (7.8%) | 56/791 (7.1%) | 54/792 (6.8%) | |
| Crude OR (95% CI) | 1.00 | 0.86 (0.61, 1.21) | 0.78 (0.55, 1.10) | 0.70 (0.49, 0.99) | 0.67 (0.46, 0.96) | 0.01 |
| Adjusted OR (95% CI)2 | 1.00 | 0.87 (0.62, 1.23) | 0.81 (0.57, 1.16) | 0.74 (0.51, 1.06) | 0.72 (0.50, 1.03) | 0.04 |
1Values for intake are medians adjusted for energy intake by the residual method for each quintile.
2Adjusted for cigarette smoking (never and ever), toothbrushing frequency (1 or less, 2, and 3+ times/day), region of residence (Hokkaido and Tohoku, Kanto, Hokuriku and Tokai, Kinki, Chugoku and Shikoku, and Kyushu), and body mass index as a continuous variable.