Taveras Elsie M, Camargo Carlos A, Rifas-Shiman Sheryl L, Oken Emily, Gold Diane R, Weiss Scott T, Gillman Matthew W
Department of Ambulatory Care and Prevention, Harvard Medical School and Harvard Pilgrim Health Care, Boston, Massachusetts 02215, USA.
Pediatr Pulmonol. 2006 Jul;41(7):643-8. doi: 10.1002/ppul.20427.
Although lower birth weight associated with prematurity raises the risk of asthma in childhood, few prospective studies have examined higher birth weight, and few have separated the two components of birth weight, fetal growth and length of gestation.
To examine the associations of fetal growth and length of gestation with asthma-related outcomes by age 2 years.
We studied 1,372 infants and toddlers born after 34 weeks' gestation in Project Viva, a prospective cohort study of pregnant mothers and their children. The main outcome measures were parent report of (1) any wheezing (or whistling in the chest) from birth to age 2 years, (2) recurrent wheezing during the first 2 years of life, and (3) doctor's diagnosis of asthma, wheeze or reactive airway disease ("asthma") by age 2. We calculated gestational age from the last menstrual period or ultrasound examination, and determined birth weight for gestational age z-value ("fetal growth") using US national reference data.
Infants' mean birth weight was 3,527 (SD, 517; range, 1,559-5,528) grams. By age 2 years, 34% of children had any wheezing, 14% had recurrent wheezing, and 16% had doctor-diagnosed asthma. After adjusting for several parent, child, and household characteristics in logistic regression models, we found that infants with birth weight > or = 4,000 g were not more likely to have any wheezing (odds ratio (OR), 0.91; 95% confidence interval (CI): 0.62, 1.34) or doctor-diagnosed asthma (OR, 0.80; 95% CI: 0.49, 1.31) than infants with birth weight 3,500-3,999 g. In models examining length of gestation and fetal growth separately, neither the highest nor the lowest groups of either predictor were associated with the three outcomes. Boys had a higher incidence of asthma-related outcomes than girls, and exposure to passive smoking, parental history of asthma, and exposure to older siblings were all associated with greater risk of recurrent wheeze or asthma-related outcomes at age 2 years.
Although male sex, exposure to smoking, parental history of asthma, and exposure to older siblings were associated with increased risk of wheezing and asthma-related outcomes in this prospective study of children born after 34 weeks gestation, fetal growth and length of gestation were not.
尽管早产相关的低出生体重会增加儿童患哮喘的风险，但很少有前瞻性研究探讨高出生体重情况，且几乎没有研究将出生体重的两个组成部分，即胎儿生长和妊娠期长度区分开来。
研究胎儿生长和妊娠期长度与2岁时哮喘相关结局之间的关联。
我们在“活力计划”中对1372名妊娠34周后出生的婴幼儿进行了研究，该计划是一项针对孕妇及其子女的前瞻性队列研究。主要结局指标包括父母报告的：（1）从出生到2岁时的任何喘息（或胸部哮鸣）；（2）生命最初2年内的反复喘息；（3）2岁时医生诊断的哮喘、喘息或反应性气道疾病（“哮喘”）。我们根据末次月经日期或超声检查计算胎龄，并使用美国国家参考数据确定出生体重相对于胎龄的z值（“胎儿生长”）。
婴儿的平均出生体重为3527（标准差517；范围1559 - 5528）克。到2岁时，34%的儿童有任何喘息，14%有反复喘息，16%有医生诊断的哮喘。在逻辑回归模型中对多个父母、儿童和家庭特征进行调整后，我们发现出生体重≥4000克的婴儿与出生体重在3500 - 3999克的婴儿相比，出现任何喘息（优势比（OR）为0.91；95%置信区间（CI）：0.62，1.34）或医生诊断哮喘（OR为0.80；95%CI：0.49，1.31）的可能性并无更高。在分别研究妊娠期长度和胎儿生长的模型中，两种预测因素的最高组和最低组均与这三种结局无关。男孩哮喘相关结局的发生率高于女孩，暴露于被动吸烟环境、父母有哮喘病史以及接触年长同胞均与2岁时反复喘息或哮喘相关结局的更高风险相关。
在这项对妊娠34周后出生儿童的前瞻性研究中，尽管男性性别、暴露于吸烟环境、父母有哮喘病史以及接触年长同胞与喘息和哮喘相关结局的风险增加有关，但胎儿生长和妊娠期长度并非如此。
