Prevalence of chronic rhinosinusitis without/with nasal polyps according to severity in Spain

Background: The worldwide prevalence range of chronic rhinosinusitis (CRS) is 5-12%; from this, 20 % have nasal polyps. Due to the little epidemiological data about CRS in the Spanish population, this study analyses the prevalence and severity of CRS with (CRSwNP) or without (CRSsNP) nasal polyps, and their connection with other coexisting type 2 inflammatory diseases in Spain. Methodology: This is a retrospective, large-scale, nationwide, epidemiological study based on the electronic medical records from the BIG-PAC® database. Patients diagnosed of CRSsNP and CRSwNP were identified using specific disease codes. The severe form of the disease was defined as patients who received at least a long course of antibiotics in CRSsNP or ≥2 short courses of systemic corticosteroids in CRSwNP in ≤12 months during the last 2 years, and/or had previous sinus surgery. Physician-diagnosed prevalence, sociodemographic and clinical characteristics, and disease severity were assessed. Results: Out of a cohort of 1,012,257 patients (≥18 years old), 42,863 and 7,550 patients with diagnosed CRSsNP and CRSwNP, respectively, were analysed. The overall prevalence of diagnosed CRS was 5.1%, being 4.3% and 0.8% for CRSsNP and CRSwNP, respectively. Patients with CRSwNP and severe forms of the disease were older and had higher levels of type 2 inflammatory biomarkers than CRSsNP patients and non-severe disease. Conclusions: Although CRSsNP was more prevalent than CRSwNP, the severe forms of CRS were more frequent in patients with CRSwNP. In addition, CRSwNP patients had a higher incidence of coexisting type 2 inflammatory diseases.