We updated the meta-analysis published by McDonald et al. [Chest 2002;122;1535-1542] by reviewing the effectiveness of air purification for the treatment of home-related allergic asthma (dust mite, dog, cat, and cockroach). We analysed the trials included by McDonald et al. as well as studies published since 2000. Data on asthma symptoms scores (ASS), medication use, forced expiratory volume in 1 s as a percentage of the predicted value (FEV1 %pred), histamine provocative concentration causing a 20% reduction in FEV1 (PC20), Asthma Quality of Life Questionnaire (AQLQ) scores, and fractional exhaled nitric oxide (FeNO) levels were extracted. The effectiveness was examined using metafor (registered in Prospero CRD42019127227). Ten trials including a total of 482 patients (baseline characteristics: mean FEV1 %pred 83.2%, I2 = 96.7%; mean PC20 4.93 mg/mL, I2 = 44.0%; mean AQLQ 4.67 [max. 7], I2 = 93.7%; mean FeNO 36.5 ppb, I2 = 0%) were included. We assessed the mean differences in the AQLQ scores as +0.36 (95% CI 0.10 to 0.62, p = 0.01, n = 302, I2 = 0%) and the FeNO levels as -6.67 ppb (95% CI -10.56 to -2.77, p = 0.0008, n = 304, I2 = 0%). The standardised mean differences in all other health outcomes were not significant (ASS -0.68, p = 0.20; medication use: -0.01, p = 0.94; FEV1 %pred -0.11, p = 0.34; PC20 +0.24, p = 0.53). We found statistically significant mean differences in the AQLQ scores and FeNO levels in patients with predominantly mild to moderate asthma at baseline. A large trial reported great improvement in the subgroup of patients receiving Global Initiative for Asthma step 4 therapy. We recommend that future studies on air purification focus on patients with severe and poorly controlled allergic asthma.

中文翻译：

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空气净化策略治疗过敏性哮喘的有效性：荟萃分析。

我们更新了McDonald等人发表的荟萃分析。[Chest 2002; 122; 1535-1542]综述了空气净化在治疗家庭相关过敏性哮喘（螨虫，狗，猫和蟑螂）中的有效性。我们分析了麦当劳等人的研究。以及自2000年以来发表的研究。有关哮喘症状评分（ASS），药物使用，1 s内呼气量占预测值（FEV1％pred）的百分比，组胺激发浓度导致FEV1降低20％的数据（ PC20），哮喘生活质量调查表（AQLQ）分数和呼出一氧化氮（FeNO）分数被提取。使用metafor（在Prospero CRD42019127227中注册）检查了有效性。十项试验共482例患者（基线特征：平均FEV1％pred 83.2％，I2 = 96.7％;平均PC20 4。93 mg / mL，I2 = 44.0％；平均AQLQ 4.67 [max。7]，I2 = 93.7％；平均FeNO 36.5 ppb，I2 = 0％）。我们评估了AQLQ得分的平均差异为+0.36（95％CI为0.10至0.62，p = 0.01，n = 302，I2 = 0％）和FeNO水平为-6.67 ppb（95％CI -10.56至-2.77） ，p = 0.0008，n = 304，I2 = 0％）。所有其他健康结局的标准化平均差异均不显着（ASS -0.68，p = 0.20；药物使用：-0.01，p = 0.94； FEV1％pred -0.11，p = 0.34； PC20 + 0.24，p = 0.53）。我们发现在基线时以轻度至中度哮喘为主的患者，AQLQ评分和FeNO水平在统计学上具有显着性差异。一项大型试验报告说，接受全球哮喘第4步治疗计划的患者亚组有了很大改善。