School of Medicine, Deakin University, Waurn Ponds, VIC, Australia.
Child Health Research Unit, Barwon Health, Geelong, VIC, Australia.
Allergy. 2017 Aug;72(8):1222-1231. doi: 10.1111/all.13122. Epub 2017 Feb 23.
Ecological evidence suggests vitamin D insufficiency (VDI) due to lower ambient ultraviolet radiation (UVR) exposure may be a risk factor for IgE-mediated food allergy. However, there are no studies relating directly measured VDI during early infancy to subsequent challenge-proven food allergy.
To prospectively investigate the association between VDI during infancy and challenge-proven food allergy at 1 year.
In a birth cohort (n = 1074), we used a case-cohort design to compare 25-hydroxyvitamin D (25(OH)D ) levels among infants with food allergy vs a random subcohort (n = 274). The primary exposures were VDI (25(OH)D <50 nM) at birth and 6 months of age. Ambient UVR and time in the sun were combined to estimate UVR exposure dose. IgE-mediated food allergy status at 1 year was determined by formal challenge. Binomial regression was used to examine associations between VDI, UVR exposure dose and food allergy and investigate potential confounding.
Within the random subcohort, VDI was present in 45% (105/233) of newborns and 24% (55/227) of infants at 6 months. Food allergy prevalence at 1 year was 7.7% (61/786), and 6.5% (53/808) were egg-allergic. There was no evidence of an association between VDI at either birth (aRR 1.25, 95% CI 0.70-2.22) or 6 months (aRR 0.93, 95% CI 0.41-2.14) and food allergy at 1 year.
There was no evidence that VDI during the first 6 months of infancy is a risk factor for food allergy at 1 year of age. These findings primarily relate to egg allergy, and larger studies are required.
生态学证据表明，由于环境紫外线（UVR）暴露减少导致的维生素 D 不足（VDI）可能是 IgE 介导的食物过敏的一个危险因素。然而，目前尚无研究直接将婴儿期早期测量的 VDI 与随后经挑战证实的食物过敏联系起来。
前瞻性研究婴儿期 VDI 与 1 岁时经挑战证实的食物过敏之间的关系。
在一项出生队列研究（n=1074）中，我们采用病例-队列设计比较了食物过敏婴儿（n=257）与随机亚队列（n=274）的 25-羟维生素 D（25（OH）D）水平。主要暴露是出生时和 6 个月时的 VDI（25（OH）D＜50nm）。环境 UVR 和晒太阳时间相结合，以估算 UVR 暴露剂量。1 岁时通过正式挑战确定 IgE 介导的食物过敏状态。二项式回归用于检查 VDI、UVR 暴露剂量与食物过敏之间的关联，并探讨潜在的混杂因素。
在随机亚队列中，45%（105/233）的新生儿和 24%（55/227）的 6 个月婴儿存在 VDI。1 岁时食物过敏的患病率为 7.7%（61/786），其中 6.5%（53/808）为鸡蛋过敏。在出生时（aRR 1.25，95%CI 0.70-2.22）或 6 个月时（aRR 0.93，95%CI 0.41-2.14）的 VDI 与 1 岁时的食物过敏之间没有证据表明存在关联。
在婴儿期的前 6 个月内，VDI 不是 1 岁时食物过敏的危险因素。这些发现主要与鸡蛋过敏有关，需要更大规模的研究。
