Exposure to sunlight and allergic morbidity in children from the PARIS birth cohort

• Published in: Revue française d'allergologie (2009) 2024-04, Vol.64, p.103999, Article 103999
• Main Authors: Lefebvre, L., Rancière, F., Roda, C., Amazouz, H., Momas, I.
• Format: Article
• Language: English
• ISSN: 1877-0320; 1877-0320
• DOI: 10.1016/j.reval.2024.103999

Sunlight relationship with allergies is poorly studied in children. The aim of this study was to examine how early exposure to solar radiation is associated with allergic morbidity in the PARIS birth cohort. This study dealt with children who attended at least one of the two health check-ups: 18months (n=2012) and 8/9years (n=1080). Early exposure (prenatal and during the first year of life) to solar radiation was assessed using meteorological data (solar radiation, temperature, relative humidity). Children with similar exposure trajectories were grouped by longitudinal and multidimensional cluster analysis. Association of solar radiation exposure with allergic morbidity (i.e. allergic sensitisation at 18months and 8/9 y., current asthma, rhinitis, and eczema at 8/9 y.) was quantified by multivariable logistic regression models adjusted for potential confounders. The effect modification of maternal vitamin D (VitD) supplementation during pregnancy was also tested. Four exposure trajectories were found. The trajectory with the highest exposure to early solar radiation had a reduced risk of sensitisation at 8/9 y. compared to the trajectory with the lowest exposure (P=0.06). The association was statistically significant in the VitD supplemented group. Solar radiation during pre- and post-natal period was significantly associated with a lower risk of sensitisation at 8/9 y. (for the augmentation of one IQR, aOR: 0.47; 95% CI: 0.25–0.87 and 0.84; 0.70–1.00, respectively). Increased prenatal exposure to solar radiation was significantly associated with a lower asthma risk at 8/9 y. (for the augmentation of one IQR: 0.32; 0.10–0.96). Early sunlight exposure may reduce the risk of sensitisation and asthma in school-aged children, especially in those prenatally exposed to VitD intake. These findings highlight the importance of VitD in preventing allergic diseases in children, either through supplementation or sunlight exposure.