Perzanowski M S, Canfield S M, Chew G L, Mellins R B, Hoepner L A, Jacobson J S, Goldstein I F
Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, NY 10032, USA.
Clin Exp Allergy. 2008 Jun;38(6):968-76. doi: 10.1111/j.1365-2222.2008.02967.x. Epub 2008 Mar 18.
In past research, children with older siblings were more likely than others to wheeze at age 2 years, but less likely by age 6 years. Higher infection transmission and a down-regulated allergic immune response as a result of these infections, respectively, were suggested as the causes. However, in a study of children aged 0-3 years in a low-income urban community in New York City, USA, with high asthma prevalence, we observed no birth-order effect.
To evaluate the association between birth order and atopy and respiratory symptoms in 4-year-old children attending Head Start programs in NYC.
Respiratory symptoms were assessed by questionnaire for 1005 children (mean age 4.0 years) living in high asthma prevalence neighbourhoods. Serum was collected from a subgroup of the children (n=494) and specific IgE responses to dust mite, cockroach, mouse, and cat allergens were measured.
Prevalence of specific IgE (> or =0.35 IU/mL) did not differ significantly among first (35%), second (35%), and later-born children (28%) (P=0.23). Increasing birth order was associated with increasing prevalence of respiratory symptoms in the prior year, including wheeze (first 20%, second 27%, third or later 35%; P<0.001), being awakened at night by cough (28%, 33%, 38%; P=0.005), emergency department visits (14%, 17%, 21%; P=0.02) and hospitalizations for difficulty breathing (6.1%, 6.6%, 10%; P=0.04). The associations of birth order with respiratory symptoms were statistically significant only for the non-seroatopic children and those without an asthmatic parent.
Non-seroatopic children with older siblings were more likely than those without older siblings to have respiratory symptoms at age 4 years. Although the stability of these associations over time remains to be determined, the differences in findings between this study and our previous NYC birth cohort study suggest that patterns of asthma development may vary even among low-income populations within the same city.
在过去的研究中，有哥哥姐姐的儿童在2岁时比其他儿童更容易出现喘息，但在6岁时则不太可能出现。分别认为较高的感染传播以及这些感染导致的过敏免疫反应下调是其原因。然而，在美国纽约市一个哮喘患病率较高的低收入城市社区对0至3岁儿童进行的一项研究中，我们未观察到出生顺序效应。
评估纽约市参加“启智计划”项目的4岁儿童的出生顺序与特应性和呼吸道症状之间的关联。
通过问卷调查对生活在哮喘患病率较高社区的1005名儿童（平均年龄4.0岁）的呼吸道症状进行评估。从一部分儿童（n = 494）中采集血清，并测量对尘螨、蟑螂、小鼠和猫过敏原的特异性IgE反应。
特异性IgE（≥0.35 IU/mL）的患病率在头胎（35%）、二胎（35%）和其他出生顺序的儿童（28%）之间无显著差异（P = 0.23）。出生顺序增加与前一年呼吸道症状患病率增加相关，包括喘息（头胎20%，二胎27%，三胎及以后35%；P < 0.001）、因咳嗽夜间醒来（28%，33%，38%；P = 0.005）、急诊就诊（14%，17%，21%；P = 0.02）以及因呼吸困难住院（6.1%，6.6%，10%；P = 0.04）。出生顺序与呼吸道症状的关联仅在非血清特应性儿童和无哮喘父母的儿童中具有统计学意义。
有哥哥姐姐的非血清特应性儿童在4岁时比没有哥哥姐姐的儿童更易出现呼吸道症状。尽管这些关联随时间的稳定性仍有待确定，但本研究与我们之前在纽约市进行的出生队列研究结果的差异表明，即使在同一城市的低收入人群中，哮喘发展模式也可能有所不同。
