Research on allergic rhinitis improvement in asthmatic children after dust mite exposure reduction: a randomized, double-blind, cross-placebo study protocol

BACKGROUND: Allergic rhinitis (AR) in children is a major respiratory inflammatory disease with a high incidence that is increasing yearly. In China, 54.93% of children with asthma have AR, which often requires synchronous treatment. House dust mites (HDMs) are common allergens that often cause attacks of AR and asthma. Reducing allergen exposure is one of the most important measures to control and treat AR and asthma attacks. Hestelia Mite Bait, containing 0.1% emamectin, is a new tool for trapping and killing dust mites, reducing the number of dust mites on mattresses and thereby potentially reducing stimulation by allergens and ultimately improving asthma and rhinitis symptoms. This single-centre, randomized, double-blind, cross-placebo trial will explore the improvement in AR in asthmatic children after dust mite exposure reduction. METHODS: We will recruit 60 children (aged 3–12 years) who have been diagnosed with AR and asthma and are allergic to dust mites as confirmed by a serum allergen test. Participants will randomly receive the Hestelia Mite Bait intervention for 8 weeks and the placebo intervention for 8 weeks. There will be a 4-week washout period between the two interventions. The primary outcome is the visual analogue scale (VAS) score of AR symptoms; the secondary outcomes include the Rhinitis Control Assessment Test (RCAT) score, Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) score, changes in the dust mite level, drug usage for asthma and AR, Asthma Control Questionnaire-5 (ACQ-5) score, and frequencies of acute asthma attacks, emergency visits, and hospitalizations. DISCUSSION: This study aims to scientifically and objectively evaluate the effects of mite bait on rhinitis and asthma improvement after dust mite exposure reduction and provides a convenient means for future prevention and treatment of allergic diseases involving the airways in children. TRIAL REGISTRATION: www.chictr.org.cn ChiCTR1900024688. Registered on July 21, 2019