Supervisors info:
Σιαχανίδου Σουλτάνα, Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Τσολιά Μαρία, Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Μίχος Αθανάσιος, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Summary:
Background / Aim: Bronchiolitis is one of the most common lower respiratory tract infections in children. The immunomodulatory action of vitamin D appears to influence the inflammatory response to respiratory infections. The aim of this study is to determine the serum levels of 25-OH vitamin D in children with bronchiolitis and to investigate a potential association between 25-OH vitamin D levels and the severity of bronchiolitis.
Methods: A cross-sectional study was performed from October 1st,2023 till June 30th, 2024. Included in the research were all patients aged below 24 months, who were hospitalized for bronchiolitis at the Second Pediatric Department and at the Neonatal Unit of the First Pediatric Department of EKPA, at the Children's Hospital "Agia Sophia". All patients had their disease severity assessed using the Modified Tal Score (MTS) and their serum 25-OH-Vitamin D levels were measured. For the data analysis, statistical analysis such as Fisher Exact, Mann Whitney, Kruskal Wallis, correlation tests, and univariate and multivariate linear regression models was used.
Results: A total of 97 children participated in the study. Of them, 54 (55.7%) were boys and 43 (44.3%) were girls. The median age of the children was 4 months (IQR: 2.25-11,5). Among the study population, 48 (49.4%) children had mild disease, 46 (47.4%) had moderate disease, and 3 (3.2%) had severe bronchiolitis. In 39.1% of the children, the cause of bronchiolitis was RSV. The mean value of serum 25-OH vitamin D was 34.08 ng/ml with a standard deviation of 12.4 ng/ml, whereas 33 children (34%) had inadequate levels (< 30 ng/ml). Serum 25-OH vitamin D levels were lower in patients with RSV bronchiolitis compared to those with bronchiolitis from other causes (p = 0.047). In the overall study population, it was observed that lower levels of 25-OH vitamin D were associated with a higher MTS score (p=0.09). Specifically, in patients with serum 25-OH vitamin D levels < 20 ng/ml, the median MTS score was 7, while in those with vitamin D levels > 20 ng/ml, the median MTS score was 5 (p=0.034). Children with serum 25-OH vitamin D levels <10 ng/ml required supplemental oxygen for at least twice as long and had to stay in hospital longer than 15 days, compared to patients with higher vitamin D levels. It was found that for every 1 ng/ml increase in 25-OH vitamin D levels, the length of hospitalization decreased by 5 hours.
Conclusion: Low serum levels of 25-OH vitamin D appear to be a risk factor for more severe disease in children with bronchiolitis, particularly when vitamin D levels are below 20 ng/ml.
Keywords:
25-OH vitamin D, Vitamin D, Bronchiolitis, Modified Tal Score, RSV
