Relationship between prenatal and postnatal exposures to folate and risks of allergic and respiratory diseases in early childhood

Abstract

A relatively high maternal serum folate level in mid-pregnancy was associated with a decreased risk of LRTIs and AD in early childhood.

Association of prenatal folate status with early childhood wheeze and atopic dermatitis

“…Our results are consistent with those of an Australian Birth Cohort Study which reported that 3rd trimester serum folate levels were not associated with infant atopic dermatitis . In contrast, the Generation R study found slightly increased atopic dermatitis at age 4 in Dutch children born to mothers with 1st trimester plasma folate >16.2 nmol/L (~7 ng/mL), and higher mid‐pregnancy serum folate (>9.5 ng/mL) was associated with decreased atopic dermatitis at 2 years in a South Korean cohort …”

“…25 In contrast, the Generation R study found slightly increased atopic dermatitis at age 4 in Dutch children born to mothers with 1st trimester plasma folate >16.2 nmol/L (~7 ng/mL), 7 and higher mid-pregnancy serum folate (>9.5 ng/mL) was associated with decreased atopic dermatitis at 2 years in a South Korean cohort. 15 The mechanisms behind potential effects of folate on child wheeze are not clear. Potentially, folate may act as an antioxidant 26 or may reduce inflammation via altering the immune system through epigenetic changes.…”

“…High prenatal folic acid exposure has been studied as a risk factor for childhood atopic diseases, due in part to its recognized capacity to epigenetically modify DNA . Some observational studies have suggested that higher folic acid during pregnancy may be associated with increased risk of allergic and respiratory phenotypes in offspring, while other studies found null or inverse associations …”

“…4 Some observational studies have suggested that higher folic acid during pregnancy may be associated with increased risk of allergic and respiratory phenotypes in offspring, [5][6][7][8][9][10] while other studies found null [11][12][13][14] or inverse associations. 13,15 Women of childbearing age are advised to consume a daily supplement of 400-800 μg/d of folic acid to reduce the risk of infants born with neural tube defects. 16 In the USA, mandatory folic acid fortification of many enriched cereal and grain products has been implemented since 1998 to achieve sufficient intake, particularly among women who may have unplanned pregnancies.…”

Pediatric Pulmonologyyear in review 2015: Part 1

“…Viral lower respiratory tract infection (LRTI) in young children continues to be of intense research interest, not least because since it may predispose to asthma and decrements in lung function in later life. Studies of risk factors for severe LRTI found that increased levels of maternal folate in mid pregnancy are associated with a decreased risk of LRTI by 6 months of age, and correlate with cord blood IL‐10 Levels and inversely with cord blood eosinophil counts, while bronchiolitis cases with blood eosinophilia had an increased length of hospital stay (LOS) and were more often mechanically ventilated (24.2%) than those without eosinophilia (7.2%) or without blood counts (0.7%) . Geographic clustering of LRTI cases identified air pollution and poor housing as community level risk factors for wheezing LRTI and viral LRTI, respectively, with higher socio‐economic status reducing the risk .…”