As-needed versus regular intranasal corticosteroid for allergic rhinitis: A systematic review and meta-analysis

Background: Daily intranasal corticosteroid (INCS) is recommended for treating allergic rhinitis (AR). Nevertheless, patients are generally not adherent and use it on-demand. The data on the efficacy of as-needed INCS was insufficient. Objective: We conducted a systematic review and meta-analysis to assess the efficacy of as-needed INCS compared with regular use for AR. Methods: We searched PubMed/MEDLINE, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials for randomized controlled trials (RCTs) until May 2021. A pairwise meta-analysis used a random-effects model to estimate the pooled standardized mean difference (SMD). The primary outcome was the total nasal symptom score (TNSS) changes from baseline at 4 and 6 weeks. Secondary outcomes were the changes of individual nasal symptom score and quality-of-life (QoL) score. Results: We identified five eligible RCTs with a total of 436 patients with AR. Only four studies had adequate data for quantitative synthesis. The TNSS changes of as-needed INCS were not significantly different from the regular use at both 4 (SMD 0.23 [95%CI:-0.14 to 0.60], p = 0.230) and 6 weeks (SMD 0.21 [95%CI:-0.02 to 0.44], p = 0.080). Most of the changes of individual nasal symptom scores and QoL scores were not significantly different between the two regimens. At 50% or more INCS dose of regular use, as-needed and regular INCS provided a similar efficacy. The treatment effect was, however, less sustained with as-needed INCS. Conclusion: The efficacy of as-needed use of INCS at 50% of corticosteroid exposure was comparable to regular use in improving nasal symptoms and QoL.