Chronic rhinosinusitis with polyposis and serum vitamin D levels

The pathogenesis of chronic rhinosinusitis (CRS) is still unknown, but it is accepted that various inflammatory factors are responsible for the different CRS subtypes. Vitamin D3 has been shown to alter inflammatory mediators in some diseases and its deficiency might also be associated with CRS with nasal polyposis (CRSwNP). Herein, we investigated serum vitamin D3 levels in patients with CRSwNP and its association with disease severity. In a cross-sectional study, 166 cases with CRSwNP and 172 healthy subjects were enrolled. Serum vitamin D3 levels were measured and compared in both groups. Furthermore, the relationship between serum vitamin-D3 level and the patient’s allergic status and severity of disease (clinically and based on computed tomographic imaging and nasal endoscopy) among patients with CRSwNP was assessed. Serum vitamin D3 level in the CRSwNP group was significantly lower than in the control group (P < 0.0001). After controlling for possible confounding factors, an increase in vitamin D level showed a protective effect in CRSwNP (OR = 0.69 95% CI:0.62-0.76). A negative correlation was found between serum vitamin-D3 level and the Lund-Mackay score (LMS) (P < 0.0001, R = – 0.66), the Lund-Kennedy score (LKS) (P < 0.0001, R = – 0.71) and the Sino-Nasal Outcome Test-22 (P < 0.001, R = – 0.49). Serum vitamin D level in the CRSwNP group was significantly lower than the control group. Disease severity, based on imaging, endoscopic and clinical criteria, was inversely associated with serum vitamin D levels.