Clinical implications of mucosal remodeling from chronic rhinosinusitis

Background: Prognostic implications of mucosal remodeling in chronic rhinosinusitis (CRS) remain unclear. Remodeling of respiratory mucosa in asthma is associated with greater medication use and decreased function. This study investigates the implications of mucosal remodeling on long-term clinical outcomes in patients with CRS. Methods: A case-control study of adult patients with CRS undergoing endoscopic sinus surgery (ESS) was performed. Mucosal remodeling was defined by squamous metaplasia, subepithelial fibrosis, and/or basement membrane thickening. The presence of remodeling changes were assessed relative to clinical and treatment outcomes at a minimum of 12 months postoperatively. Clinical outcomes were assessed at baseline and 12 months using a Nasal Symptom Score (NSS) and 22-item Sino-Nasal Outcome Test (SNOT-22). Treatment outcomes were assessed by oral corticosteroid usage (burst/continuous), topical corticosteroid irrigation frequency, and further surgical intervention. Results: A total of 110 patients (48.73 ± 14.75 years, 48.2% female) were assessed. Significant improvements where seen for the entire population, in both NSS (2.64 ± 1.06 to 1.34 ± 1.08, p < 0.001) and SNOT-22 (2.05 ± 0.96 to 1.06 ± 0.79, p < 0.001). Patients with remodeling (n = 88) were younger (47.2 ± 14.8 vs 54.7 ± 13.5 years, p = 0.03), but had similar symptom scores. Remodeling was seen in CRS with nasal polyposis (CRSwNP) (54.5%) and eosinophilic chronic rhinosinusitis (eCRS) (59.8%). Symptom improvement at 12 months was similar between remodeled and non-remodeled groups (NSS: Δ1.34 ± 1.20 vs Δ1.12 ± 1.31, p = 0.395; SNOT-22: Δ1.05 ± 0.91 vs Δ0.73 ± 0.95, p = 0.124); however, patients with remodeling had greater corticosteroid irrigation frequency (64.0% vs 31.6% daily use, Kendall's tau-b p = 0.004). Conclusion: Established mucosal remodeling predicts a greater reliance on topical therapies to reach similar clinical endpoints as those without remodeling.