TABLE 1.
Participant# characteristics according to quartiles of preformed vitamin A intake at 7 years of age
| Quartiles of preformed vitamin A intake | p-value | ||||
| Quartile 1 | Quartile 2 | Quartile 3 | Quartile 4 | ||
| Participants | 1359 (25.2) | 1343 (24.9) | 1350 (25.1) | 1332 (24.7) | |
| Preformed vitamin A intake μg·day–1 | 261±58.4 | 382±27.6 | 480±31.3 | 680±173.6 | |
| Male | 638 (46.9) | 627 (46.7) | 663 (49.1) | 731 (54.9) | <0.001 |
| Older siblings | 742 (54.6) | 720 (53.6) | 686 (50.8) | 639 (48.0) | 0.002 |
| Younger siblings | 624 (45.9) | 674 (50.2) | 717 (53.1) | 782 (58.7) | <0.001 |
| Total energy intake kJ·day–1 | 6214±1291 | 7136±1189 | 7890±1235 | 9139±1728 | <0.001 |
| BMI kg·m−2 | 16.2±2.1 | 16.0±1.9 | 16.2±2.0 | 16.2±1.9 | 0.04 |
| Health-conscious dietary pattern score | −0.27±0.89 | −0.08±0.88 | 0.07±0.94 | 0.33±1.05 | <0.001 |
| Season of dietary information collection | 0.31 | ||||
| Winter | 339 (24.9) | 354 (26.4) | 347 (25.7) | 339 (25.5) | |
| Spring | 424 (31.2) | 393 (29.3) | 398 (29.5) | 370 (27.8) | |
| Summer | 366 (26.9) | 373 (27.8) | 381 (28.2) | 395 (29.7) | |
| Autumn | 207 (15.2) | 214 (15.9) | 214 (15.9) | 213 (16.0) | |
| Missing | 23 (1.7) | 9 (0.7) | 10 (0.7) | 15 (1.1) | |
| History of food allergy | 263 (19.4) | 219 (16.3) | 221 (16.4) | 234 (17.6) | 0.12 |
| Any supplement use | 450 (33.1) | 440 (32.8) | 453 (33.6) | 461 (34.6) | 0.76 |
| Protein intake g·day−1 | 52.8±12.2 | 61.1±11.5 | 66.7±11.6 | 77.2±15.8 | <0.001 |
| Vitamin C intake mg·day–1 | 68.2±31.4 | 72.9±32.5 | 78.2±33.0 | 85.3±35.8 | <0.001 |
| Vitamin D intake mg·day–1 | 2.14±0.7 | 2.69±0.8 | 3.01±0.9 | 3.45±1.1 | <0.001 |
| Vitamin E intake mg·day–1 | 7.49±2.6 | 9.23±2.9 | 10.32±3.3 | 11.83±4.0 | <0.001 |
| Zinc intake mg·day–1 | 5.19±1.3 | 5.99±1.3 | 6.57±1.3 | 7.66±1.8 | <0.001 |
| VLC n-3 PUFA intake from fish mg·day–1 | 65.9±73.3 | 77.9±84.6 | 83.8±91.0 | 98.7±99.2 | <0.001 |
| Parental factors | |||||
| Maternal age at pregnancy years | 29.5±4.4 | 29.4±4.4 | 29.5±4.4 | 29.1±4.5 | 0.02 |
| Maternal education | 0.21 | ||||
| Secondary or vocational | 281 (20.7) | 267 (19.9) | 237 (17.6) | 236 (17.7) | |
| O-level | 464 (34.1) | 450 (33.5) | 476 (35.3) | 451 (33.9) | |
| A-level or degree | 593 (43.6) | 608 (45.3) | 624 (46.2) | 619 (46.5) | |
| Missing | 21 (1.5) | 18 (1.3) | 13 (1.0) | 26 (2.0) | |
| Housing tenure during pregnancy | |||||
| Mortgaged/owned | 1156 (85.1) | 1136 (84.6) | 1151 (85.3) | 1071 (80.4) | |
| Council rented | 74 (5.4) | 71 (5.3) | 74 (5.5) | 107 (8.0) | |
| Non-council rented | 74 (5.4) | 71 (5.3) | 68 (5.0) | 91 (6.8) | |
| Missing | 55 (4.0) | 65 (4.8) | 57 (4.2) | 63 (4.7) | |
| Financial difficulty during pregnancy | 0.24 | ||||
| No | 1156 (85.3) | 1136 (85.4) | 1153 (85.9) | 1105 (83.3) | |
| Yes | 200 (14.8) | 195 (14.7) | 189 (14.1) | 222 (16.7) | |
| Maternal ethnicity | 0.02 | ||||
| White | 1307 (96.2) | 1297 (96.6) | 1324 (98.1) | 1292 (97.0) | |
| Non-White | 25 (1.8) | 27 (2.0) | 11 (0.8) | 14 (1.1) | |
| Missing | 27 (2.0) | 19 (1.4) | 15 (1.1) | 26 (2.0) | |
| Maternal history of atopy | 0.12 | ||||
| No | 713 (52.5) | 712 (53.0) | 700 (51.9) | 652 (48.9) | |
| Yes | 594 (43.7) | 579 (43.1) | 613 (45.4) | 622 (46.7) | |
| Missing | 52 (3.8) | 52 (3.9) | 37 (2.7) | 58 (4.4) | |
| Paternal history of atopy | 0.02 | ||||
| No | 584 (43.0) | 601 (44.8) | 553 (41.0) | 582 (43.7) | |
| Yes | 414 (30.5) | 385 (28.7) | 470 (34.8) | 388 (29.1) | |
| Missing | 361 (26.6) | 357 (26.6) | 327 (24.2) | 362 (27.2) | |
| Maternal smoking | 0.01 | ||||
| No | 1085 (79.8) | 1102 (82.1) | 1100 (81.5) | 1020 (76.6) | |
| Yes | 219 (16.1) | 194 (14.4) | 201 (14.9) | 257 (19.3) | |
| Missing | 55 (4.0) | 47 (3.5) | 49 (3.6) | 55 (4.1) | |
| Preformed vitamin A intake at 32 weeks of gestation μg·day–1 | 302±249 | 335±276 | 357±319 | 414±379 | <0.001 |
Data are presented as n (%) or mean±sd, unless otherwise specified. BMI: body mass index; VLC n-3 PUFA: very-long-chain ω-3 polyunsaturated fatty acid. #: children included in incident asthma or lung function analysis (n=5384).