Association of Serum Vitamin D Levels in Patients with Allergic Rhinitis at a Tertiary Care Health Centre in Bihar

Background: Allergic rhinitis (AR) is a chronic inflammatory nasal disorder mediated by IgE and is becoming increasingly common worldwide. Apart from its role in calcium metabolism, vitamin D has regulatory functions in immunity that may influence AR severity. Objective: To evaluate the relationship between an individual's severity of allergic rhinitis and their serum vitamin D levels. Methods: A retrospective cross-sectional study was conducted over the course of year the IGIMS, Patna. A total of 156 patients with clinically diagnosed AR were included after informed consent. Serum 25-hydroxyvitamin D was estimated using the Architect Abbott i2000 CMIA system. Patients with comorbidities or taking drugs affecting vitamin D were excluded. GraphPad Prism 8.0 was used for statistical analysis. Results: Most AR patients were vitamin D deficient (<20 ng/mL). Those with deficiency had a significantly higher prevalence of moderate-to-severe persistent AR compared to individuals with sufficient levels (>30 ng/mL). An inverse correlation between vitamin D concentration and AR severity was observed (p<0.05). Conclusion: Vitamin D deficiency is widespread among allergic rhinitis patients in Bihar and is strongly linked with more severe disease. Incorporating vitamin D screening and correction into routine management may help improve clinical outcomes