Vitamin D and Asthma: Association with Pulmonary Function and Eosinophilic Inflammation

INTRODUCTION: Asthma is a chronic inflammatory airway disease marked by variable airflow obstruction and bronchial hyperresponsiveness. Vitamin D, known for its immunomodulatory properties, has been suggested to influence asthma pathophysiology, potentially affecting pulmonary function and eosinophilic inflammation. This study aims to investigate the differences in vitamin D levels between asthmatic patients and healthy individuals, and to analyze the correlation of vitamin D with pulmonary function, arterial oxygen saturation, and eosinophilic inflammation markers.
METHODS: This retrospective observational study reviewed medical records from 147 asthmatic patients and 30 healthy controls at a research hospital from January 2022 to January 2023. Pulmonary function tests, arterial oxygen saturation, and eosinophilic markers (eosinophil count, eosinophil percentage, total immunoglobulin E (IgE), and eosinophil cationic protein (ECP) levels) were analyzed.
RESULTS: No significant difference in vitamin D levels was observed between asthmatic patients and healthy controls (p=0.543). A weak positive correlation was found between vitamin D levels and peak expiratory flow (PEF)% (r=0.185, p=0.025). No significant correlations were observed between vitamin D levels and other pulmonary function parameters or eosinophilic markers.
DISCUSSION AND CONCLUSION: While vitamin D levels did not differ significantly between asthmatic and healthy individuals, a weak positive correlation with PEF% suggests a potential role in improving expiratory flow. No significant association was found with other pulmonary functions or eosinophilic inflammation markers. Further studies are needed to clarify the role of vitamin D in asthma management.

Keywords: Asthma, eosinophil cationic protein, immunoglobulin E, lung function tests, Vitamin D