Table 4.
Categorized duration of breastfeeding and timing of introduction of complementary foods and risk of IA (any IA or GADA)
| IA | Dietary exposure* | Timing in months* | Number of children who developed any IA or GADA, N (%) | Number of children who did not develop any IA or GADA, N (%) | Unadjusted HR (95% CI) | P value | Adjusted† HR (95% CI) | P value |
|---|---|---|---|---|---|---|---|---|
| Any IA | Gluten-containing cereals | <4 | 28 (6) | 445 (94) | 0.68 (0.47, 0.99) | 0.047 | 0.67 (0.54, 0.98) | 0.037 |
| 4–9 | 637 (10) | 6,048 (90) | 1 | 1 | ||||
| >9 | 31 (14) | 185 (86) | 1.57 (1.07, 2.31) | 0.022 | 1.44 (0.97, 2.16) | 0.074 | ||
| Any breastfeeding | ≤7 | 334 (9) | 3,575 (91) | 0.93 (0.80, 1.08) | 0.326 | 0.94 (0.81, 1.09) | 0.426 | |
| >7 | 360 (11) | 3,042 (89) | 1 | 1 | ||||
| Cow’s milk | ≤5 | 584 (10) | 5,922(91) | 0.83 (0.68, 1.00) | 0.055 | 0.85 (0.69, 1.04) | 0.115 | |
| >5 | 117 (11) | 902 (89) | 1 | 1 | ||||
| Cereals | ≤4 | 483 (9) | 4,765 (91) | 0.99 (0.85, 1.17) | 0.945 | 1.09 (0.92, 1.30) | 0.309 | |
| >4 | 216 (10) | 2,045 (90) | 1 | 1 | ||||
| Rice | ≤7 | 618 (9) | 6,196 (91) | 0.79 (0.63, 0.99) | 0.046 | 0.87 (0.69, 1.10) | 0.233 | |
| >7 | 75 (13) | 502 (87) | 1 | 1 | ||||
| Fruit and berries | ≤4 | 460 (9) | 4,552 (91) | 0.99 (0.85, 1.15) | 0.868 | 1.00 (0.85, 1.18) | 0.999 | |
| >4 | 240 (10) | 2,254 (90) | 1 | 1 | ||||
| Potato | ≤7 | 578 (10) | 5,345 (90) | 1.19 (0.98, 1.45) | 0.077 | 0.98 (0.77, 1.25) | 0.898 | |
| >7 | 121 (8) | 1,353 (92) | 1 | 1 | ||||
| Meat | ≤8 | 615 (10) | 5,762 (90) | 1.27 (1.01, 1.59) | 0.040 | 1.13 (0.88, 1.45) | 0.344 | |
| >8 | 77 (8) | 914 (92) | 1 | 1 | ||||
| Egg | ≤9 | 282 (9) | 3,002 (91) | 0.86 (0.74, 0.99) | 0.045 | 0.84 (0.72, 0.99) | 0.035 | |
| >9 | 402 (10) | 3,456 (90) | 1 | 1 | ||||
| GADA | Any breastfeeding | ≤6 | 120 (3) | 3,476 (97) | 1.20 (0.95, 1.52) | 0.126 | 1.17 (0.92, 1.49) | 0.196 |
| >6 | 174 (5) | 3,541 (95) | 1 | 1 | ||||
| Rice | ≤6 | 264 (4) | 6,435 (96) | 1.25 (0.87, 1.78) | 0.224 | 1.10 (0.76, 1.58) | 0.623 | |
| >6 | 28 (4) | 664 (96) | 1 | 1 | ||||
| Fish and seafood | ≤9 | 188 (4) | 4,538 (96) | 0.88 (0.70, 1.12) | 0.290 | 1.11 (0.81, 1.53) | 0.507 | |
| >9 | 92 (4) | 2,054 (96) | 1 | 1 |
*Dietary exposure: timing of breastfeeding or food; categorization of timing of gluten-containing cereals’ introductions was based on martingale residuals whereas dichotomizations of timing of other dietary exposures in relation to the risk of any IA or GADA were based on change-point methods using log-rank test (28); only statistically significant (P < 0.05) cut points are shown. No statistically significant cut point of timing of a dietary exposure for IAA was detected.
†The Cox regression model was adjusted for country, HLA genotype, FDR status, sex of the child, and probiotic use <28 days.