Carswell F, Birmingham K, Oliver J, Crewes A, Weeks J
Institute of Child Health, Royal Hospital for Sick Children, Bristol, UK.
Clin Exp Allergy. 1996 Apr;26(4):386-96.
Inhalation of house dust mite (HDM) allergen may provoke attacks of asthma.
We investigated whether a double-blind placebo-controlled community-based study aimed at reducing the HDM allergens in the bedrooms of HDM sensitive asthmatic children using the best methods available would prove beneficial to the children's health.
The children (mean age 9.9 years, 34 boys) were recruited by a questionnaire submitted to 7386 families in a geographically-defined area of the UK. Subjects were chosen to take part in the double-blind placebo-controlled trial if they were asthmatic, skin sensitive to mites, and had mite allergen in their mattresses. Seventy children were randomly allocated to groups. In the active group, the children's bedrooms were treated with an acaricide (Acarosan) and the mattresses, pillows and duvets were encased in exclusion covers. The control group received placebo treatments.
Forty-nine complete data sets were obtained. Applying bedding covers and Acarosan led to a median reduction of 480 ng (100%) in mite allergen on the mattress vs 215 ng (53%) reduction in placebo-treated group by 6 weeks. No evidence was found that the acaricide reduced mite allergen level. A change in bronchial reactivity to histamine was observed in the children after 6 weeks. This was not associated with any change in thrice-daily records of peak expiratory flow rate. By 24 weeks, the actively-treated children had improved forced expiratory volume in 1s (FEV1) and fewer required bronchodilator therapy or reported asthmatic symptoms than did the controls.
The results suggest that mite removal procedures may modestly improve mite-sensitive asthmatics and could perhaps be of value in exceptionally mite-sensitive and/or highly mite-exposed individuals whose response to the attempted removal should be measured.
吸入屋尘螨（HDM）过敏原可能引发哮喘发作。
我们调查了一项基于社区的双盲安慰剂对照研究，该研究旨在使用现有最佳方法减少对HDM敏感的哮喘儿童卧室中的HDM过敏原，是否对儿童健康有益。
通过向英国一个地理区域内的7386个家庭发放问卷招募儿童（平均年龄9.9岁，34名男孩）。如果儿童患有哮喘、对螨虫皮肤敏感且床垫中有螨虫过敏原，则被选入双盲安慰剂对照试验。70名儿童被随机分组。在活性组中，儿童卧室用杀螨剂（Acarosan）处理，床垫、枕头和羽绒被用防螨套包裹。对照组接受安慰剂治疗。
获得了49个完整数据集。到6周时，使用床上用品套和Acarosan使床垫上的螨虫过敏原中位数减少480纳克（100%），而安慰剂治疗组减少215纳克（53%）。未发现杀螨剂降低螨虫过敏原水平的证据。6周后观察到儿童对组胺的支气管反应性发生了变化。这与每日三次记录的呼气峰值流速的任何变化均无关。到24周时，积极治疗的儿童一秒用力呼气容积（FEV1）有所改善，与对照组相比，需要支气管扩张剂治疗或报告哮喘症状的儿童更少。
结果表明，清除螨虫程序可能适度改善对螨虫敏感的哮喘患者，对于对螨虫极度敏感和/或螨虫暴露量高的个体可能有价值，应对这些个体尝试清除螨虫后的反应进行评估。
