Elevated Serum IL-33 and VEGF Levels in Preschool Children with Recurrent Wheezing

Recurrent wheezing (RW) is a common respiratory condition in preschool children and is associated with an increased risk of subsequent asthma development. Interleukin (IL)-33 and vascular endothelial growth factor (VEGF) are involved in airway inflammation and remodeling, but their role in preschool RW remains unclear. We aimed to evaluate serum IL-33 and VEGF levels and investigate their diagnostic and prognostic value in children with RW. A total of 132 children were enrolled, including 83 children with RW and 49 healthy controls. Serum IL-33 and VEGF levels were measured by enzyme-linked immunosorbent assay. Diagnostic performance was assessed using receiver operating characteristic (ROC) curve analysis. Children with RW were re-evaluated after three years for asthma development. Serum IL-33 and VEGF levels were significantly higher in children with RW than in controls (both p < 0.001). ROC analysis showed good discriminatory performance for IL-33 (AUC: 0.763, 95% CI: 0.679–0.839) and VEGF (AUC: 0.794, 95% CI: 0.714–0.872). During follow-up, 54 of 83 children (65.1%) developed asthma. Multivariable logistic regression identified elevated VEGF levels, food allergy, and a family history of asthma as independent predictors of asthma development. Each 10 pg/mL increase in VEGF was associated with a 19% increase in asthma risk (adjusted OR: 1.19, 95% CI: 1.05–1.35; p = 0.006). Serum IL-33 and VEGF levels are elevated in preschool children with RW. Elevated VEGF levels independently predict subsequent asthma development, suggesting that VEGF may serve as a non-invasive biomarker for identifying children at increased risk of future asthma.