Barrier Protection Measures for the Management of Allergic Rhinitis: A Systematic Review and Meta-analysis

Background Pharmacotherapy for allergic rhinitis (AR) still remains unsatisfying regarding its effect and safety. Barrier protection measures may be a good choice for the patients with AR. Objective To assess the efficacy and safety of barrier protection measures in the treatment of AR. Methods We selected relevant randomized controlled trials published between January 1, 1990, and February 20, 2019, by searching Embase, PubMed, Cochrane, Web of Knowledge, and ClinicalTrials.gov. The primary outcome for this analysis was rhinitis symptom scores, overall quality of life, nasal peak inspiratory flow (NPIF), and adverse events. Differences were expressed as weighted mean difference (WMD) with 95% confidence intervals (CIs) for continuous outcomes. Statistical heterogeneity across trials was assessed with the statistic ( P < .1) and the I 2 statistic. Results Fifteen RCTs (with data for 1154 participants) satisfied our inclusion criteria. The types of barrier protection measures comprised cellulose, pollen blocker cream, microemulsion, and nasal filter. To reduce the potential risk of bias and heterogeneity, we carried out subgroup analysis according to different types of barrier protection measures (cellulose: WMD = –2.18, 95% CI, –3.01 to –1.35, P < .00001; pollen blocker cream: WMD = –4.55, 95% CI, –6.10 to –3.00, P < .00001; microemulsion: WMD = –0.22, 95% CI, –0.42 to –0.03, P = .03). Findings from our meta-analysis show that, compared with placebo, barrier protection measures can yield improved symptomatic control for AR, with no increase in adverse events. Furthermore, barrier protection measures can improve the quality of life and NPIF. Conclusion Although further studies are still needed, our findings clearly lend support to barrier protection measures as a safe and efficacious option for the treatment of AR patients.