Low Vitamin D Levels in Early Childhood Linked to Asthma among infants with bronchiolitis: Study
Researchers have found in a new study that Children with a history of severe bronchiolitis in infancy who had low serum 25-hydroxyvitamin D (< 20 ng/mL) at age 3 had a higher risk of developing eosinophilic asthma or eosinophilia without asthma by age 6.
Beyond its well-known function in calcium homeostasis and bone health, vitamin D plays an important role in immune modulation and, possibly, the etiology of allergic diseases.
Studies have shown an association between vitamin D deficiency and asthma incidence and control. Moreover, there is an association between early-life blood eosinophil levels and asthma incidence, consistent with a distinct eosinophilic asthma endotype.
Pediatric studies report an inconsistent association between serum 25-hydroxyvitamin D (25[OH]D) and eosinophilia. Additionally, no studies have investigated the association between serum 25(OH)D and eosinophilic asthma among children with a history of severe (requiring hospitalization) bronchiolitis. Bronchiolitis is the most common cause of infant hospitalization in the United States and a major risk factor for childhood asthma.
The association between early childhood serum 25-hydroxyvitamin D (25(OH)D) and eosinophilic asthma remains unclear. We investigated this association using multicentre prospective data from 584 children with a history of bronchiolitis requiring hospitalisation (high-risk population). Low serum 25(OH)D levels (<20 ng/mL) were associated with increased odds of developing eosinophilic asthma (adjusted OR 2.33; 95% CI 1.23, 4.40; p=0.01) as compared with children with serum 25(OH)D of 20-39.9 ng/mL. Our data facilitate further investigation into the potential role of early-life vitamin D supplementation among children with a history of severe bronchiolitis and eosinophilia for preventing childhood asthma.
Reference:
Doumat G, El Zein J, Mehta GD, Zhu Z, Espinola JA, Sullivan AF, Hasegawa K, Camargo CA Jr. Association between vitamin D status at 3 years and eosinophilic asthma in 6-year-old children with a history of severe bronchiolitis. Thorax. 2025 Feb 17;80(3):180-183. doi: 10.1136/thorax-2024-222099. PMID: 39762022; PMCID: PMC11832317.
