Objective: Sublingual immunotherapy (SLIT) has been widely applied to treat patients with allergic rhinitis (AR). However, meta-analyses on the efficacy of SLIT in AR patients with asthma are still limited.
Methods: Literature without language limitation published before October 28, 2022, were retrieved from PubMed, EMBASE, and Cochrane Library. STATA 16.0 software was used for the meta-analysis of the extracted data. The results reported were symptom scores, drug scores, adverse effects rates, and cost of treatment.
Results: Ten studies involving 1722 patients met the inclusion criteria. The total rhinitis score (TRSS) (weighted mean difference [WMD] = -1.23, 95% CI: -1.39--1.06, P < .001) and total asthma symptom score (TASS) (WMD = -1.00, 95% CI: -1.12-0.89, P < .001) were significantly lower in the SLIT group than the placebo group. The SLIT group had higher rates of treatment-related adverse events (relative risk [RR] = 2.82, 95% CI: 1.77-4.48, P < .001) and total costs of treatment (standardized mean difference [SMD] = 0.71, 95% CI: 0.45-0.97, P < .001). There was no significant difference in inhaled corticosteroids (ICS) dose (P = .195), fractional exhaled nitric oxide (FeNO) (P = .158), forced expiratory volume in 1 s (FEV1) (P = .237), and direct costs of treatment (P = .630) between the SLIT and placebo groups.
Conclusion: SLIT may be a therapeutic method for improving rhinitis symptoms and asthma symptoms in AR patients with asthma. However, as there was significant heterogeneity in results, more high-quality and well-designed studies are needed in the future to elucidate the efficacy of SLIT.
Keywords: allergic rhinitis; asthma; efficacy; meta-analysis; sublingual immunotherapy.