Table 4 Parental-report of allergy by child’s age at follow-up and for all ages combined, and potential risk factors
Age at follow-up | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
Characteristic | 12 months (n = 2182) | 3 years (n = 1213) | 5 years (n = 627) | All ages combined | ||||||||
Total N | n with allergy | % with allergy | Total N | n with allergy | % with allergy | Total N | n with allergy | % with allergy | Total person-years | Rate ratio | RR [95% CI] | |
Gender | ||||||||||||
Male | 1094 | 93 | 8.5% | 571 | 56 | 9.8%* | 211 | 36 | 17.1%** | 2658 | 69.6 | 1.4 [1.2,1.8] |
Female | 1028 | 74 | 7.2% | 607 | 37 | 6.1% | 226 | 19 | 8.4% | 2693 | 48.3 | 1.0 (Reference) |
Maternal Indigenous status | ||||||||||||
Not indigenous | 2065 | 159 | 7.7% | 1177 | 93 | 7.9% | 433 | 55 | 12.7% | 5286 | 58.1 | 1.0 (Reference) |
ATSI | 29 | 4 | 13.8% | 0 | 0 | 0.0% | 0 | 0 | 0.0% | 29 | 138.0 | 1.8 [0.6, 4.7] |
Birthweight | ||||||||||||
< 2500 g | 59 | 7 | 11.8% | 33 | 3 | 9.1% | 0 | 0 | 0.0% | 125 | 79.8 | 1.3 [0.7, 2.5] |
≥ 2500 g | 1905 | 160 | 8.4% | 1154 | 90 | 7.8% | 426 | 55 | 12.9% | 4212 | 59.3 | 1.0 (Reference) |
Season of birth | ||||||||||||
Summer/Spring | 1873 | 148 | 7.9% | 958 | 68 | 7.1% | 389 | 44 | 11.3% | 4568 | 56.9 | 1.0 (Reference) |
Autumn/Winter | 301 | 22 | 7.3% | 240 | 25 | 10.4% | 56 | 12 | 21.4% | 894 | 66.0 | 1.2 [0.8, 1.5] |
Maternal education | ||||||||||||
Did not complete high school | 312 | 29 | 9.3% | 186 | 21 | 11.3% | 64 | 7 | 10.9% | 812 | 70.2 | 1.2 [0.9, 1.6] |
Completed high school | 1679 | 141 | 8.4% | 1000 | 72 | 7.2% | 380 | 49 | 12.9% | 4438 | 59.0 | 1.0 (Reference) |
Household income (annual) | ||||||||||||
< $40,000 | 347 | 26 | 7.5% | 175 | 11 | 6.3% | 60 | 11 | 18.3% | 816 | 58.8 | 0.8 [0.7, 1.1] |
$40,000 - $70,000 | 635 | 47 | 7.4% | 357 | 25 | 7.0% | 144 | 15 | 10.4% | 1638 | 53.1 | |
≥ $70,000 | 906 | 77 | 8.5% | 511 | 47 | 9.2% | 188 | 24 | 12.8% | 2303 | 64.3 | 1.0 (Reference) |
Other children living in household | ||||||||||||
0 | 973 | 72 | 7.4% | 492 | 32 | 6.5% | 176 | 25 | 14.2% | 2310 | 55.9 | 1.0 (Reference: 0–2) |
1–2 | 734 | 47 | 6.4% | 418 | 33 | 7.9% | 167 | 18 | 10.8% | 1903 | 51.5 | |
3 or more | 532 | 50 | 9.4% | 276 | 27 | 9.8% | 95 | 13 | 13.7% | 1273 | 70.7 | 1.3 [1.0, 1.7] |
Child care attendance (in first year of life) | ||||||||||||
Yes | 571 | 52 | 9.1% | 816 | 62 | 7.6% | Not applicable | 2203 | 51.7 | 1.0 (Reference) | ||
No | 1575 | 115 | 7.3% | 380 | 30 | 7.9% | 2335 | 62.1 | 1.2 [0.9, 1.5] | |||
Breast feeding before discharged newborn | ||||||||||||
Yes | 1072 | 89 | 8.3% | 524 | 33 | 6.3% | 204 | 23 | 11.3% | 2527 | 57.4 | 1.2 [0.7, 2.1] |
N0 | 106 | 5 | 4.7% | 51 | 5 | 9.8% | 30 | 3 | 10.0% | 268 | 48.4 | 1.0 (Reference) |
Not asked | 935 | 72 | 7.7% | 604 | 55 | 9.1% | 200 | 29 | 14.5% | 2544 | 61.3 | Not included |
Ever breast-fed by 12 months of age | ||||||||||||
Yes | 2025 | 160 | 7.9% | 1053 | 80 | 7.6% | 408 | 53 | 13.0% | 4946 | 59.2 | 1.1 [0.6, 1.9] |
No | 132 | 9 | 6.8% | 63 | 5 | 7.9% | 0 | 0 | 0.0% | 259 | 54.1 | 1.0 (Reference) |
Breastfeeding duration | ||||||||||||
0–3 months | 720 | 59 | 8.2% | 361 | 26 | 7.2% | 138 | 17 | 12.3% | 1718 | 59.4 | 1.0 (Reference all < 6 months) |
3–6 months | 388 | 31 | 8.0% | 196 | 9 | 4.6% | 77 | 9 | 11.7% | 933 | 52.5 | |
> 6 months | 500 | 36 | 7.2% | 276 | 27 | 9.8% | 105 | 19 | 18.1% | 1261 | 65.0 | 1.1 [0.9, 1.5] |
Age at first consumption of solids | ||||||||||||
0–3 months | 286 | 24 | 8.4% | 143 | 5 | 3.5% | 48 | 5 | 10.4% | 668 | 50.9 | 1.0 (Reference all < 6 months) |
3–6 months | 1759 | 139 | 7.9% | 916 | 76 | 8.3% | 350 | 42 | 12.0% | 4291 | 59.9 | |
> 6 months | 92 | 7 | 7.6% | 55 | 5 | 9.1% | 26 | 6 | 23.1% | 254 | 70.9 | 1.2 [0.8, 1.9] |
Smoking during pregnancy | ||||||||||||
Yes | 423 | 41 | 9.7% | 247 | 19 | 7.7% | 89 | 5 | 5.6%* | 1095 | 59.4 | 1.0 [0.8, 1.3] |
No | 1743 | 129 | 7.4% | 949 | 74 | 7.8% | 355 | 50 | 14.1% | 4350 | 58.2 | 1.0 (Reference) |
Use of antibiotics (in first year of life) | ||||||||||||
None | 335 | 69 | 20.6%** | 232 | 44 | 19%*** | 41 | 7 | 17.1% | 880 | 136.4 | 2.3 [1.6, 3.2]a |
1–4 prescriptions | 226 | 21 | 9.3% | 167 | 12 | 7.2% | 47 | 7 | 14.9% | 653 | 61.2 | 4.2 [2.3, 8.4]b |
5+ prescriptions | 34 | 4 | 11.7% | 128 | 5 | 3.9% | 7 | 1 | 13.9% | 305 | 32.8 | |