Does BMI Modify the Association between Vitamin D and Pulmonary Function in Children of the Mild Asthma Phenotype?

Area of Science:

• Pediatric Pulmonology
• Nutritional Immunology
• Asthma Research

Background:

• Vitamin D deficiency and obesity are prevalent global health issues.
• Both conditions are linked to an increased risk of childhood asthma.
• Understanding their interplay is crucial for managing pediatric asthma.

Purpose of the Study:

• To investigate if Body Mass Index (BMI) influences pulmonary function in pediatric asthma patients with mild asthma.
• To examine the association between vitamin D levels and lung function across different BMI categories.

Main Methods:

• Cross-sectional study of 61 Greek schoolchildren (5-12 years) with mild asthma.
• Participants were stratified into normal-weight and overweight/obese groups.
• Lung function assessed via spirometry (% FVC, % FEV1) and fractional exhaled nitric oxide (FeNO); serum 25(OH)D levels categorized.

Main Results:

• In normal-weight children, higher vitamin D levels correlated positively with % FVC and % FEV1.
• Normal-weight children with sufficient vitamin D (≥30 ng/mL) had significantly higher FEV1 compared to deficient children.
• No significant associations were found between vitamin D and lung function in overweight/obese children or for FeNO.

Conclusions:

• Body Mass Index (BMI) significantly modifies the relationship between vitamin D status and airway mechanics in children with mild asthma.
• Sufficient vitamin D levels are associated with improved central airway ventilation in normal-weight children with mild asthma.
• These findings highlight the importance of considering both BMI and vitamin D status in managing pediatric mild asthma.