哮喘联盟

摘要
   背景：前期有关评价出生体重在哮喘风险中作用的研究价值有限，因为存在选择偏倚和协变量失衡。
   目的：采用倾向评分法评价出生体重和哮喘风险的关系。
   方法：本试验是一项基于1976年1月1日至1979年12月31日美国明尼苏达州罗切斯特出生的儿童队列的回顾性队列研究。采用16个协变量构建出生体重的倾向评分计算公式。在倾向评分对数0.2 SD范围内的低出生体重（<2,500 g）儿童，匹配倾向评分。采用Kaplan-Meier 曲线计算低出生体重组和正常出生体重组的哮喘累计发病率。
   结果：在1976年1月1日至1979年12月31日之间共有3933名儿童出生。匹配之前，193名低出生体重儿童中有13名出现哮喘(6.7%) ，3740名正常体重儿童中201名出现哮喘(5.4%)(P=0.42).两组之间存在明显的协变量失衡。然而，在倾向评分匹配后，协变量失衡显著下降，低出生体重儿童与正常体重儿童具有相似的哮喘风险(8.3% vs 7.3%, P=0.75).
   结论：在6岁以内，出生体重与哮喘风险无关。倾向评分对于有关哮喘流行病学的观察性研究来说是一种有用的方法。

 

（刘国梁 审校）
Ann Allergy Asthma Immunol. 2013 Jan;110(1):18-23. doi: 10.1016/j.anai.2012.10.010. Epub 2012 Nov 10.

Population-based study on association between birth weight and risk of asthma: A propensity score approach.

Yang HJ, Qin R, Katusic S, Juhn YJ.

Source
Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota; Department of Pediatrics, Soonchunhyang University Hospital, Seoul, South Korea.

Abstract
BACKGROUND: Previous studies that assessed the role of birth weight in the risk of asthma have been limited because of selection bias and covariate imbalance.
OBJECTIVE: To assess the association between birth weight and risk of asthma by applying a propensity score approach.
METHODS: The study was designed as a retrospective cohort study based on a birth cohort of children born between January 1, 1976, and December 31, 1979, in Rochester, Minnesota. The propensity scores for birth weight were formulated using 16 covariates. We matched the propensity scores for children having low birth weight (<2,500 g) within a caliper of 0.2 SD of logit function of propensity scores. We calculated the cumulative incidence of asthma between low and normal birth weight groups using the Kaplan-Meier curve.
RESULTS: There were 3933 eligible children born between January 1, 1976, and December 31, 1979. Before matching, 13 of the 193 children (6.7%) born weighing 2,500 g developed asthma, whereas 201 of the 3,740 children (5.4%) born weighing 2,500 g and above developed asthma (P=.42). There were significant covariate imbalances between comparison groups. However, after propensity score matching, covariate imbalance was significantly reduced, and children born weighing less than 2,500 g had a similar risk to matched children born with normal birth weight (8.3% vs 7.3%, P=.75).
CONCLUSION: Birth weight is not associated with risk of asthma during the first 6 years of life. The propensity score may be a useful method for observational studies concerning asthma epidemiology.

Ann Allergy Asthma Immunol. 2013 Jan;110(1):18-23. doi: 10.1016/j.anai.2012.10.010. Epub 2012 Nov 10.