INMA: “Prenatal and child vitamin D levels and allergy and asthma in childhood”

19/03/2024

An INMA study shows that having higher vitamin D levels at pre-school age might be related with a lower chance of eczema in childhood. A recent study by Sangüesa et al. used data from the INMA-Asturias, Gipuzkoa, Menorca, Sabadell, and Valencia cohorts to evaluate the relationship between vitamin D levels and allergy and asthma in childhood.

The prevalence of vitamin D deficiency can be up to 75% in adults, even in Southern European countries where there is a lot of sunshine. Pregnant women and infants in particular are at an increased risk. Vitamin D is important for the development of the immune system, and a deficiency can be linked to allergy and asthma in childhood. While most previous studies only look at allergic and asthma symptoms at one time point, this study goes a step further by examining the effect of vitamin D levels during both pregnancy and childhood.

The current investigation used information on vitamin D levels recorded during the INMA study, during pregnancy for around 2500 participants and at 4 years of childhood for around 800 participants. Answers from questionnaires collected between 1 to 9 years were used to determine whether the child had: allergic rhinitis, atopic eczema, wheeze, and/or asthma.

Around 19% of mothers and 24% of children had a vitamin D deficiency. The study concluded that having a higher vitamin D level at a pre-school age was associated with a smaller chance of having eczema during childhood. Also, having a higher vitamin D level during pregnancy and childhood might lower the chance of late-onset wheezing.

The study builds on existing literature relating to the possible positive effect of vitamin D levels in children of pre-school age on atopic eczema. This could be because vitamin D plays a role in preventing inflammation responses and infections. However, the authors highlight the importance of further studies to evaluate vitamin D levels during pregnancy and childhood, and their relationship with allergic and asthma symptoms later in childhood.

Reference: Sangüesa J, Sunyer J, Garcia-Esteban R, Abellan A, Esplugues A, Garcia-Aymerich J, Guxens M, Irizar A, Júlvez J, Luque-García L, Rodríguez-Dehli AC, Tardón A, Torrent M, Vioque J, Vrijheid M, Casas M. Prenatal and child vitamin D levels and allergy and asthma in childhood. Pediatr Res. 2023 May;93(6):1745-1751.

Link to scientific article: https://pubmed.ncbi.nlm.nih.gov/36057646/