Copenhagen Prospective Studies on Asthma in Childhood; Health Sciences, University of Copenhagen, Copenhagen, Denmark.
Am J Respir Crit Care Med. 2012 Jun 1;185(11):1183-9. doi: 10.1164/rccm.201110-1922OC. Epub 2012 Mar 29.
The causal direction between asthma and lung function deficit is unknown, but important for the focus of preventive measures and research into the origins of asthma.
To analyze the interaction between lung function development and asthma from birth to 7 years of age.
The Copenhagen Prospective Studies on Asthma in Childhood is a prospective clinical study of a birth cohort of 411 at-risk children. Spirometry was completed in 403 (98%) neonates and again by age 7 in 317 children (77%).
Neonatal spirometry and bronchial responsiveness to methacholine was measured during sedation by forced flow-volume measurements. Asthma was diagnosed prospectively from daily diary cards and clinic visits every 6 months. Children with asthma by age 7 (14%) already had a significant airflow deficit as neonates (forced expiratory flow at 50% of vital capacity second in neonates reduced by 0.34 z score by 1 mo; P = 0.03). This deficit progressed significantly during early childhood (forced expiratory flow at 0.5 seconds in neonates at age 7 reduced by 0.82 z score by age 7; P < 0.0001), suggesting that approximately 40% of the airflow deficit associated with asthma is present at birth, whereas 60% develops with clinical disease. Environmental tobacco exposure, but not allergic sensitization, also hampered airflow growth. Bronchial responsiveness to methacholine in the neonates was associated with the development of asthma (P = 0.01).
Children developing asthma by age 7 had a lung function deficit and increased bronchial responsiveness as neonates. This lung function deficit progressed to age 7. Therefore, research into the origins and prevention of asthma should consider early life before and after birth.
哮喘与肺功能缺陷之间的因果关系尚不清楚，但对于预防措施的重点和哮喘起源的研究很重要。
分析从出生到 7 岁期间肺功能发育与哮喘之间的相互作用。
哥本哈根儿童哮喘前瞻性研究是一项对高危儿童队列的前瞻性临床研究，共纳入 411 名儿童。403 名（98%）新生儿进行了肺功能检测，其中 317 名（77%）儿童在 7 岁时再次进行了检测。
通过强制流量-容积测量对镇静状态下的新生儿进行肺功能检测和气道反应性检测。通过日常日记卡和每 6 个月一次的门诊随访前瞻性诊断哮喘。7 岁时患有哮喘的儿童（14%）在新生儿期已经存在明显的气流受限（新生儿第 50%肺活量呼气流量降低 0.34 个 z 评分，1 个月时 P = 0.03）。这一缺陷在儿童早期显著进展（新生儿 0.5 秒呼气流量在 7 岁时降低 0.82 z 评分，P < 0.0001），表明与哮喘相关的气流受限约有 40%在出生时就存在，而 60%则随着临床疾病的发展而出现。环境烟草暴露而不是过敏致敏也会阻碍气流增长。新生儿气道反应性与哮喘的发生相关（P = 0.01）。
7 岁时患有哮喘的儿童在新生儿期就存在肺功能缺陷和气道反应性增加。这种肺功能缺陷一直持续到 7 岁。因此，对于哮喘的起源和预防的研究应该考虑出生前后的早期生命阶段。
