Early Folic Acid Supplement Initiation and Risk of Adverse Early Childhood Respiratory Health: A Population-based Study.

Objectives Folate plays a vital role in biologic functions yet women often do not meet the recommended dietary intake in pregnancy. It has been suggested that high folic acid intake during pregnancy may increase the risk of respiratory diseases in offspring. However, findings from observational studies in human populations are inconclusive. Methods In this population-based study, we collected self-reported folic acid and prenatal vitamin supplement use during pregnancy 3-6 months postpartum from mothers in Los Angeles whose children were born in 2003. Supplement initiation was based on whichever supplement, either folic acid or prenatal supplements, the women initiated first. In a 2006 follow-up survey, approximately 50% of women were re-contacted to gather information on the child's respiratory health, including symptoms and diagnoses, at approximately 3.5 years of age. Results Overall, timing of folic acid supplement initiation was not associated with wheeze or lower respiratory tract infection, even after accounting for preterm births and censoring at follow-up. However, children born to mothers with a history of atopy (hay fever, eczema or asthma) who initiate folic acid supplements in late pregnancy, compared to first trimester initiators, have 1.67 (95% CI 1.12, 2.49) times the risk of wheeze in the first 3 years of life and 1.88 (95% CI 1.05, 3.34) times the risk of wheeze in the past year. No association was found among children of non-atopic mothers. Conclusions These findings suggest that early folic acid or prenatal supplementation among atopic women may be important to prevent wheeze among offspring.

The Influence of Pre-natal Supplement Initiation on Preterm Birth Among Majority Hispanic Women in Los Angeles County: The Role of Nativity.

Objectives Despite being encouraged to take pre-natal supplements, suboptimal micronutrient intake is common in pregnancy, especially among Hispanic women. In this study, we assessed whether initiation and timing of pre-natal vitamin use influences the risk of preterm birth. Methods Women who gave birth to singletons in 2003 in Los Angeles County, California, were enrolled into a population-based case-control study. Focusing on non-Hispanic white and Hispanic women, associations between timing of pre-natal supplement use and preterm birth were assessed using logistic regression. Results Among Hispanic mothers, the odds of preterm birth increased the later a woman initiated pre-natal supplement use in pregnancy. The magnitude of this association was larger in US-born compared to foreign-born Hispanic women. Conclusions These findings suggest that nativity may modify the relationship between pre-natal supplement use and preterm birth possibly due to underlying differences in diet composition of Hispanic women by place of birth.

Blood concentrations of methionine, selenium, beta-carotene, and other micronutrients in a case-control study of arsenic-induced skin lesions in West Bengal, India.

Previous studies have suggested that susceptibility to arsenic toxicity could be influenced by micronutrients, in particular selenium, methionine, and beta-carotene. A case-control study was conducted in West Bengal, India, in a region known to have groundwater arsenic contamination, to determine whether differences in micronutrient status contribute to susceptibility to arsenic-induced skin lesions. Micronutrient status was assessed by blood levels of specific micronutrients and metabolic indicators. Blood was obtained from 180 cases with skin lesions and 192 controls. Blood assays measured micronutrients and carotenoids (folate, selenium, vitamin B12, vitamin B6, retinol, alpha-tocopherol, lutein/zeaxanthin, beta-carotene, lycopene, beta-cryptoxanthin) and metabolic indicators such as glucose, cholesterol, transthyretin, amino acids, and proteins potentially associated with methylation (cysteine, homocysteine, methionine, glutathione). The distributions of nutrient concentrations were similar in cases and controls. The median selenium concentrations in cases and controls were both 1.15 micromol/L, and there was little evidence of differences in other micronutrients. Odds ratios (ORs) for arsenic-induced skin lesions were estimated for each quartile of nutrient concentrations, using the quartile with the highest nutrient level as the referent group. There were no clear trends associated with deficiencies of any micronutrient or metabolic indicator. For decreasing quartiles of selenium, the OR estimates were 1.00, 0.67, 0.99, 0.80; P=0.81; for methionine, the OR estimates were 1.00, 0.83, 0.78, 0.72; P=0.29. For beta-carotene, the ORs were 1.00, 0.53, 0.51, 0.96, demonstrating no increased risk at the lower quartiles. The measured micronutrients and metabolic indicators investigated do not appear to modify the risk of developing arsenic-induced skin lesions. The lack of any trend of increasing risk with lower selenium, vitamin E, and beta-carotene concentrations has important implications for proposed therapeutic interventions. The emphasis of interventions should be on reducing arsenic exposure.

Children’s health and environment: a review of evidence: a joint report from the European Environment Agency and the WHO Regional Office for Europe

Children’s health needs to be protected from environmental threats. This publication is a first contribution towards assessing the extent of the impact of environmental quality on children’s health. Through the close cooperation of the European Environment Agency and the WHO Regional Office for Europe with shared goals, it provides an overview of the available evidence of the relationship between the physical environment and children's health, identifying both research needs and policy priorities to protect children’s health from environmental hazards.