Table 2.
Association between frequency of bowel movements and cumulative incidence of atopic dermatitis
| Frequency of bowel movements | ||||
|
| ||||
| Alomost everyday | 5–6 times/wk | 3–4 times/wk | ≤2 times/wk | |
| Cumulative incidence until 3 years of age | ||||
| No. at risk | 54,672 | 2,624 | 4,631 | 850 |
| No. of cases (%) | 12,328 (22.6) | 598 (22.8) | 1043 (22.5) | 219 (25.8) |
| Crude OR (95% CI) | ref | 1.01 (0.92–1.11) | 1.00 (0.93–1.07) | 1.19 (1.02–1.39) |
| Multivariable OR (95% CI)a | ref | 1.02 (0.93–1.12) | 1.00 (0.93–1.07) | 1.18 (1.01–1.38) |
| Cumulative incidence until 2 years of age | ||||
| No. at risk | 56,579 | 2,717 | 4,805 | 882 |
| No. of cases (%) | 9,253 (16.4) | 468 (17.2) | 778 (16.2) | 165 (18.7) |
| Crude OR (95% CI) | ref | 1.06 (0.96–1.18) | 0.99 (0.91–1.07) | 1.18 (0.99–1.40) |
| Multivariable OR (95% CI)a | ref | 1.07 (0.97–1.19) | 0.99 (0.91–1.07) | 1.18 (0.99–1.40) |
| Cumulative incidence until 1.5 years of age | ||||
| No. at risk | 57,820 | 2,782 | 4,885 | 905 |
| No. of cases (%) | 5,175 (9.0) | 263 (9.5) | 437 (9.0) | 92 (10.2) |
| Crude OR (95% CI) | ref | 1.06 (0.93–1.21) | 1.00 (0.90–1.11) | 1.15 (0.93–1.43) |
| Multivariable OR (95% CI)a | ref | 1.07 (0.94–1.22) | 1.00 (0.90–1.11) | 1.15 (0.92–1.43) |
CI: confidence interval; OR: odds ratio
aAdjusted by maternal characteristics such as mother’s age at delivery, maternal body mass index before pregnancy, maternal smoking, maternal educational status, maternal allergic history including atopic dermatitis, asthma, hay fever, food allergy, and allergic conjunctivitis. Also adjusted by child’s characteristics such as child’s sex, birth weight, mode of delivery, exclusive breastfeeding for 6 months or more, day care attendance, and pet ownership.