Kusel Merci M H, de Klerk Nicholas H, Kebadze Tatiana, Vohma Vaike, Holt Patrick G, Johnston Sebastian L, Sly Peter D
Telethon Institute for Child Health Research, Centre for Child Health Research, University of Western Australia, West Perth, Australia.
J Allergy Clin Immunol. 2007 May;119(5):1105-10. doi: 10.1016/j.jaci.2006.12.669. Epub 2007 Mar 13.
Severe lower respiratory infections (LRIs) and atopic sensitization have been identified as independent risk factors for asthma.
The nature of potential interactions between these risk factors was the subject of this study.
A community-based cohort of 198 children at high atopic risk was followed from birth to 5 years. All episodes of acute respiratory illness in the first year were recorded and postnasal aspirates were collected for viral identification. History of wheeze and asthma was collected annually, and atopy was assessed at 6 months, 2 years, and 5 years.
A total of 815 episodes of acute respiratory illness were reported, and 33% were LRIs. Viruses were detected in 69% of aspirates, most commonly rhinoviruses (48.3%) and respiratory syncytial virus (10.9%). At 5 years, 28.3% (n = 56) had current wheeze, and this was associated with wheezy [odds ratio (OR), 3.4 (1.2-9.7); P = .02] and/or febrile LRI [OR, 3.9 (1.4-10.5); P = .007], in particular those caused by respiratory syncytial virus or rhinoviruses [OR, 4.1 (1.3-12.6); P = .02]. Comparable findings were made for current asthma. Strikingly these associations were restricted to children who displayed early sensitization (< or =2 years old) and not observed in nonatopic patients or those sensitized later.
These data suggest viral infections interact with atopy in infancy to promote later asthma. Notably the occurrence of both of these events during this narrow developmental window is associated with maximal risk for subsequent asthma, which suggests a contribution from both classes of inflammatory insults to disease pathogenesis.
Protection of "high-risk" children against the effects of severe respiratory infections during infancy may represent an effective strategy for primary asthma prevention. The potential benefits of these strategies merit more careful evaluation in this age group.
严重下呼吸道感染（LRIs）和特应性致敏已被确定为哮喘的独立危险因素。
本研究的主题是这些危险因素之间潜在相互作用的性质。
对198名特应性高风险儿童的社区队列从出生随访至5岁。记录第一年所有急性呼吸道疾病发作情况，并收集鼻后抽吸物进行病毒鉴定。每年收集喘息和哮喘病史，并在6个月、2岁和5岁时评估特应性。
共报告815次急性呼吸道疾病发作，其中33%为严重下呼吸道感染。69%的抽吸物中检测到病毒，最常见的是鼻病毒（48.3%）和呼吸道合胞病毒（10.9%）。5岁时，28.3%（n = 56）有当前喘息，这与喘息性[比值比（OR），3.4（1.2 - 9.7）；P = 0.02]和/或发热性严重下呼吸道感染[OR，3.9（1.4 - 10.5）；P = 0.007]相关，特别是由呼吸道合胞病毒或鼻病毒引起的感染[OR，4.1（1.3 - 12.6）；P = 0.02]。当前哮喘也有类似发现。引人注目的是，这些关联仅限于表现出早期致敏（≤2岁）的儿童，在非特应性患者或后期致敏的患者中未观察到。
这些数据表明病毒感染在婴儿期与特应性相互作用，促进后期哮喘。值得注意的是，在这个狭窄的发育窗口期内这两个事件的发生与随后哮喘的最大风险相关，这表明这两类炎症性损伤都对疾病发病机制有影响。
保护“高危”儿童免受婴儿期严重呼吸道感染的影响可能是预防原发性哮喘的有效策略。这些策略的潜在益处值得在这个年龄组中进行更仔细的评估。
