Background: Allergic rhinitis is characterized by a Th2-dependent inflammation. Nasal obstruction largely depends on allergic inflammation.
Objective: The aim of this study was to evaluate the possible role of the symptom nasal obstruction in assessing patients with hay fever.
Methods: Fifty patients (mean age, 23.7 +/- 4.9 years) with hay fever were evaluated both during and outside pollen season. All of them had moderate-severe grade of nasal obstruction. Total symptom score (TSS), rhinomanometry, nasal lavage, nasal scraping, spirometry, and methacholine bronchial challenge were performed in all subjects.
Results: During the pollen season, patients with severe nasal obstruction showed significantly higher values of TSS, IL-4, IL-5, IL-8, nasal eosinophils and neutrophils, and significantly lower values of nasal airflow, IFNgamma, FEV1, FVC, and FEF 25-75 in comparison with patients with moderate nasal obstruction. Twenty (83%) patients with severe nasal obstruction showed bronchial hyperreactivity (BHR), whereas only 6 (25%) patients with moderate nasal obstruction had BHR. Outside the pollen season overlapping results were observed.
Conclusions: This study provides evidence about the key role played by nasal obstruction in assessing patients with allergic rhinitis.