EPIUnit - Institute of Public Health, University of Porto, Porto, Portugal.
Laboratory for Integrative and Translational Research in Population Health (ITR), Porto, Portugal.
Allergy. 2022 Jun;77(6):1719-1735. doi: 10.1111/all.15295. Epub 2022 Apr 2.
Allergen immunotherapy (AIT) is a disease-modifying treatment for IgE-mediated diseases. Randomized controlled trials (RCTs) support AIT's potential role in asthma prevention but evidence from non-randomized studies of interventions (NRSI) and longitudinal observational studies has been poorly addressed. Therefore, we aimed to conduct a systematic review and meta-analysis to assess clinical data from all study types to evaluate quantitatively the preventive role of AIT in asthma onset.
We search three databases. Studies were screened, selected and evaluated for quality using risk-of-bias (ROB) tools. Data were descriptively summarized and meta-analysed using random effects. We performed a sensitivity, influence and subgroup analyses. Publication bias and heterogeneity were assessed.
From the 4549 identified studies, 24 (12 RCTs and 12 NRSI) were included in the qualitative synthesis and 18 underwent meta-analysis. One study was at low ROB, seven had moderate ROB, and 15 were proven of high ROB. Random-effects analysis showed a significant decrease in the risk of developing asthma following AIT by 25% (RR, 95% CI: 0.75, 0.64-0.88). This effect was not significant in the sensitivity analysis. Publication bias raised concerns, together with the moderate heterogeneity between studies (I = 58%). Subgroup analysis showed a remarkable preventive effect of AIT in children (RR, 95% CI: 0.71, 0.53-0.96), when completing 3 years of therapy (RR, 95% CI: 0.64, 0.47-0.88), and in mono-sensitized patients (RR, 95% CI: 0.49, 0.39-0.61).
Our findings support a possible preventive effect of AIT in asthma onset and suggest an enhanced effect when administered in children, mono-sensitized, and for at least 3 years, independently of allergen type.
变应原免疫疗法（AIT）是一种针对 IgE 介导疾病的疾病修正治疗方法。随机对照试验（RCT）支持 AIT 在预防哮喘中的潜在作用，但非随机干预研究（NRSI）和纵向观察研究的证据尚未得到充分解决。因此，我们旨在进行系统评价和荟萃分析，以评估所有研究类型的临床数据，从而定量评估 AIT 在哮喘发病中的预防作用。
我们搜索了三个数据库。使用偏倚风险（ROB）工具筛选、选择和评估研究。使用随机效应进行描述性总结和荟萃分析。我们进行了敏感性、影响和亚组分析。评估了发表偏倚和异质性。
从 4549 项确定的研究中，24 项（12 项 RCT 和 12 项 NRSI）纳入了定性综合分析，18 项进行了荟萃分析。一项研究为低 ROB，7 项为中 ROB，15 项为高 ROB。随机效应分析显示，AIT 后哮喘发病风险降低了 25%（RR，95%CI：0.75，0.64-0.88）。在敏感性分析中，这种效果并不显著。发表偏倚引起了关注，同时研究之间存在中度异质性（I²=58%）。亚组分析显示，AIT 在儿童中具有显著的预防作用（RR，95%CI：0.71，0.53-0.96），完成 3 年治疗（RR，95%CI：0.64，0.47-0.88），以及在单敏患者中（RR，95%CI：0.49，0.39-0.61）。
我们的研究结果支持 AIT 在哮喘发病中的可能预防作用，并表明在儿童中、单敏患者中、至少治疗 3 年，以及与过敏原类型无关时，效果增强。
