Efficacy and Mechanism of Acupoint Catgut Embedding in theTreatment of Chronic Spontaneous Urticaria:Protocol for aRandomized Double-Blind Placebo-Controlled Trial

Background: Chronic spontaneous urticaria (CSU) is a common chronic inflammatory skin disease that manifests as itchingand wheals, seriously affecting quality of life. Clinical observations and previous research trials have shown that acupuncture issafe and effective for the treatment of CSU. However, there are problems, such as a short duration of action and frequent treatment.Compared with traditional acupuncture, acupoint catgut embedding (ACE) has the advantages of a longer effect and highercompliance. Clinical trials are needed to prove its efficacy and mechanism of action.Objective: This trial aims to provide definitive evidence for the treatment of CSU with ACE and explore the mechanism ofACE.Methods: This is a randomized, double-blind, placebo-controlled trial. In this trial, 108 participants aged 18-60 years with adiagnosis of CSU and no history of ACE will be randomly assigned to 2 groups (1:1 ratio) using the Statistical Analysis System:treatment (ACE) and control (sham ACE). The participants and efficacy evaluators will be blinded to the grouping. Both the ACEand sham ACE groups will undergo acupuncture, but the sham ACE group will not receive catgut sutures. Treatment will beperformed twice weekly for 8 weeks, with a 1-week run-in period and a 16-week follow-up period. Twenty patients will berandomly selected to undergo functional magnetic resonance imaging before and after the treatment period. The primary outcomewill be the urticaria activity score over 7 days (UAS7). We will use R (version 4.0.1; R Project for Statistical Computing) toperform ANOVA and independent samples ttests to compare the differences within and between groups before and after treatmentby judging the rejection range based on a significance level of .05.Results: The study protocol has been approved by the Ethics Committee of Guang'anmen Hospital on September 7, 2022, andhas been registered on November 30, 2022. Recruitment began on March 1, 2023. A total of 4-6 participants are expected to berecruited each month. The recruitment is planned to be completed on March 1, 2025, and we expect to publish our results by thewinter of 2025. As of November 1, 2023, we have enrolled 25 participants with CSU.Conclusions: This randomized, double-blind, placebo-controlled trial aims to provide definitive evidence for the treatment ofCSU with ACE and explore the mechanism of ACE. We hypothesize that wheals and itching will show greater improvement inparticipants receiving active therapy than in those receiving sham treatment. The limitations of this study include its single-centertrial design, small sample size, and short treatment duration, which may have certain impacts on the research results.Trial Registration: Chinese Clinical Trial Registry ChiCTR2200066274;https://www.chictr.org.cn/showprojEN.html?proj=179056International Registered Report Identifier (IRRID): DERR1-10.2196/54376