Protocol for the Vitamin D Oral Replacement in Asthma (VDORA) study

Area of Science:

• Pediatric Pulmonology
• Endocrinology
• Nutritional Science

Background:

• Obesity and asthma are prevalent, with obesity independently increasing asthma risk.
• Low vitamin D levels are linked to impaired lung function and increased asthma exacerbations.
• Optimal serum vitamin D levels (>40 ng/mL) for immunomodulatory effects are proposed but not established in pediatric obesity.

Purpose of the Study:

• To characterize the population pharmacokinetics (PK) of vitamin D in children with obesity and asthma.
• To determine appropriate vitamin D supplement doses for achieving proposed immunomodulatory serum levels.
• To inform future studies on vitamin D's impact on asthma symptoms in this population.

Main Methods:

• Randomized trial in children aged 6-18 years with asthma and BMI >85th percentile.
• Two arms: standard daily vitamin D dosing vs. loading dose followed by standard daily dosing.
• Blood sample analysis to determine vitamin D PK parameters.

Main Results:

• Pharmacokinetic data on vitamin D in pediatric obesity are currently unknown.
• Dosing strategies to achieve target serum vitamin D levels in this cohort require investigation.
• This study will provide crucial PK data for dose selection.

Conclusions:

• Understanding vitamin D PK in obese children with asthma is essential for effective supplementation.
• This research will guide the identification of doses needed to reach potentially therapeutic serum levels.
• Results may support the development of vitamin D interventions for asthma management in pediatric obesity.