Intranasal versus oral treatments for allergic rhinitis: a systematic review with meta-analysis

Abstract

Background: The 2020 Allergic Rhinitis and Its Impact on Asthma (ARIA) guidelines favour the use of intranasal medications for the treatment of allergic rhinitis, although, for most of these recommendations, the level of evidence was deemed "low" or "very low". Objective: We aimed to perform a systematic review and meta-analysis comparing intranasal and oral treatments' effectiveness in improving allergic rhinitis symptoms and quality of life. Methods: We searched four bibliographic databases and three clinical trial datasets for randomised controlled trials assessing patients ≥12 years old with seasonal or perennial allergic rhinitis comparing intranasal corticosteroids or antihistamines versus oral antihistamines or leukotriene receptor antagonists. We performed meta-analysis on the Total Nasal Symptom Score (TNSS), Total Ocular Symptom Score (TOSS), Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), development of adverse events and withdrawals due to adverse events. Certainty of evidence was assessed using GRADE. Results: We included 35 primary studies, most of which assessed patients with seasonal allergic rhinitis and displayed an unclear risk of bias. Intranasal treatments were more effective than oral treatments at improving the TNSS, TOSS and RQLQ, being mostly associated with clinically meaningful improvements. Overall, certainty of evidence for these comparisons was considered high or moderate. Conclusions: Intranasal treatments are more effective than oral treatments at improving allergic rhinitis symptoms and quality of life.