Low cord-serum 25-hydroxyvitamin D levels are associated with poor lung function performance and increased respiratory infection in infancy

Abstract

BackgroundPerinatal vitamin D deficiency is associated with a higher risk of wheezing in childhood. However, the relationship between vitamin D levels and lung function in infancy has not been investigated. The aim of this study was to investigate the impact of perinatal vitamin D levels on respiratory function and disease outcome in infancy.Materials and methodsFull-term infants without any chronic diseases or major anomalies were enrolled in the Prediction of Allergies in Taiwanese Children cohort study. Maternal and cord blood were collected for determining the 25(OH)D level. Questionnaires were recorded at birth and 6 months of age. Infant lung function, including tidal breathing analysis, respiratory mechanics, and forced tidal expiration, was tested at 6 months of age.ResultsA total of 122 mother—infant pairs were enrolled in this study, and 71 infants underwent lung function testing at 6 months of age. 25(OH)D levels in maternal and cord serum were highly correlated (r2 = 0.457, p < 0.0001). Infants with lower cord serum 25(OH)D levels (< 13.7 ng/ml) had higher resistance of respiratory system (p < 0.01) and a higher risk of a respiratory tract infection before the age of 6 months (p < 0.01).ConclusionAlthough a high correlation was found between maternal and cord vitamin D levels, the effect on respiratory outcome was different. Our study is the first to show that low cord 25(OH)D levels significantly relationship with poorer lung function performance and higher likelihood of a respiratory tract infection before 6 months of age.

Prenatal vitamin D status and respiratory and allergic outcomes in childhood: A meta‐analysis of observational studies

“…From 547 records retrieved by our search, 34 articles published between 2008 and 2017 were finally included (Figure ). Articles are based on 26 separate study populations, including 25 longitudinal birth cohorts and one case‐control study, from 16 different countries (latitude ranging from 55ºN to 31ºS) (Table ).…”

“…Fourteen single studies assessed the association of prenatal 25(OH)D levels with the occurrence of RTIs in the offspring from birth to 36 months of age . Results of the meta‐analysis including available data showed an inverse association between prenatal vitamin D levels and risk of RTIs in offspring.…”

“…Seven studies reported the association between prenatal 25(OH)D circulating levels with offspring's lung function from age 6 months to 8 years . The results of available data showed a positive borderline association between prenatal vitamin D levels and offspring's lung function performance (Figure ).…”

“…Ten studies assessed prenatal vitamin D status in maternal plasma or serum collected during pregnancy; one of them did it early in pregnancy (first trimester), 30 six in mid pregnancy (second trimester), 33,43,44,50,52,53 seven in late pregnancy (third trimester), 23,26,31,36,41,45,54 and one study measured vitamin D in all trimesters. 37 Eighteen studies measured vitamin D levels at birth in cord blood samples, 24,25,[27][28][29]32,34,35,[38][39][40]42,[46][47][48][49]55,56 and six studies measured vitamin D at both time points (pregnancy and birth). 36,50-54…”

The association between vitamin D status and infectious diseases of the respiratory system in infancy and childhood

“…This association was stronger in children born in fall [89]. In another birth cohort study with 122 mother-infant pairs, low 25(OH)D concentrations at delivery (< 13.7 ng/mL) was associated with a higher risk of RTI before the age of 6 months and relatively poor lung performance at the age of 6 months [90].…”