Association Between Serum Vitamin D Level and Uncontrolled Chronic Rhinosinusitis With Nasal Polyposis

Chronic rhinosinusitis with nasal polyposis (CRSwNP) is characterized by type 2 inflammation, and studies have shown that conventional therapy usually yields unsatisfactory results. While recent studies have indicated the potential effect of vitamin D on allergic and inflammatory diseases, including CRSwNP. Therefore, this study aimed to investigate the relationship between serum vitamin D levels and the severity of CRSwNP using endoscopic evaluations, imaging, patient-reported outcome measures, absolute eosinophilic count, and serum vitamin D levels and determine the prevalence of vitamin D deficiency in patients with CRSwNP.