Ambient air pollution and endocrinologic disorders in childhood

Ambient air pollution has been proposed as an important environmental risk factor that increases global mortality and morbidity. Over the past decade, several human and animal studies have reported an association between exposure to air pollution and altered metabolic and endocrine systems in children. However, the results for these studies were mixed and inconclusive and did not demonstrate causality because different outcomes were observed due to different study designs, exposure periods, and methodologies for exposure measurements. Current proposed mechanisms include altered immune response, oxidative stress, neuroinflammation, inadequate placental development, and epigenetic modulation. In this review, we summarized the results of previous pediatric studies that reported effects of prenatal and postnatal air pollution exposure on childhood type 1 diabetes mellitus, obesity, insulin resistance, thyroid dysfunction, and timing of pubertal onset, along with underlying related mechanisms.

Association of Antibiotics Exposure Within the First 2 Years After Birth with Subsequent Childhood Type 1 Diabetes

Purpose: Antibiotics prescription in early life can cause dysbiosis, an imbalance of gut microbiota. We aimed to reveal the relationship between antibiotics exposure during the first 2 years after birth and type 1 diabetes risk in children under 8 years of age using a nationally representative data from South Korea. Methods: The final study population consisted of 63,434 children from the National Health Insurance Service (NHIS) database from 2008 to 2015. The primary exposure of interest was antibiotics prescription in first 2 years after birth. The analysis was conducted with cumulative defined daily dose (cDDD; 0-29, 30-59, ≥ 60 cDDD), the number of antibiotics classes (0-3, 4, ≥ 5 classes), and age at first antibiotics prescription (0-119, 120-239, ≥ 240 days). Age, sex, household income, and overweight were considered as potential confounding covariates. Results: Compared to those within the less than 30 cDDD, other groups that were prescribed more antibiotics did not have a significant difference in diabetes risk (aHR 0.86, 95% CI 0.37-2.02 in ≥ 60 cDDD). The number of antibiotics classes and age at first antibiotics prescriptions were also not associated with the risk of type 1 diabetes. The development of diabetes was not related to the cDDD, the number of antibiotics classes, and age at first antibiotics prescription according to subgroup analysis which was stratified by overweight. Conclusions: Antibiotics exposure within the first 2 years of life was not associated with subsequent diabetes risk. Future studies using a larger number of long-term follow-up data are needed.