Corticosteroid therapy in chronic rhinosinusitis with nasal polyps: from histopathological tissue remodeling to patient adherence and barriers.

BACKGROUND AND OBJECTIVES: This study evaluated mucosal remodeling across different corticosteroid regimens and identified barriers to treatment adherence in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). PATIENTS, MATERIALS AND METHODS: We enrolled 56 consecutive patients divided into two arms: Group 1 (n=22) underwent sinus surgery after topical, systemic, or combined corticosteroid therapy, with mucosal biopsies evaluated via a four-parameter histopathological (HP) score (infiltrate, eosinophils, edema, fibrosis). Group 2 (n=34; 15 excluded due to systemic steroid use) received exclusive medical treatment and was assessed for compliance using the Medication Adherence Questionnaire (MAQ) at baseline and three months. RESULTS: In Group 1, combined therapy (topical and systemic) demonstrated significantly lower HP scores compared with the topical-only group for inflammatory infiltrate (p=0.0280), tissue eosinophils (p=0.036), intramucosal edema (p=0.0400), and fibrosis (p=0.0393). In Group 2, a strong negative correlation was established between MAQ and Medication Adherence Report Scale-5 (MARS-5) (r=-0.9216, p<0.0001), confirming validity. Early treatment discontinuation and time constraints were the primary drivers of non-adherence. CONCLUSIONS: Combined topical and systemic corticosteroid therapy yields superior tissue remodeling outcomes by significantly reducing mucosal inflammation, eosinophilia, edema, and fibrosis compared to topical therapy alone. The MAQ is a valid clinical tool, highlighting early discontinuation and time constraints as key targets to optimize patient compliance and CRSwNP management.