Brown Hilary K, Speechley Kathy Nixon, Macnab Jennifer, Natale Renato, Campbell M Karen
Department of Epidemiology and Biostatistics, The University of Western Ontario, London, Canada, Children's Health Research Institute, London, Canada, Department of Paediatrics, The University of Western Ontario, London, Canada and Department of Obstetrics and Gynaecology, The University of Western Ontario, London, CanadaDepartment of Epidemiology and Biostatistics, The University of Western Ontario, London, Canada, Children's Health Research Institute, London, Canada, Department of Paediatrics, The University of Western Ontario, London, Canada and Department of Obstetrics and Gynaecology, The University of Western Ontario, London, Canada.
Department of Epidemiology and Biostatistics, The University of Western Ontario, London, Canada, Children's Health Research Institute, London, Canada, Department of Paediatrics, The University of Western Ontario, London, Canada and Department of Obstetrics and Gynaecology, The University of Western Ontario, London, CanadaDepartment of Epidemiology and Biostatistics, The University of Western Ontario, London, Canada, Children's Health Research Institute, London, Canada, Department of Paediatrics, The University of Western Ontario, London, Canada and Department of Obstetrics and Gynaecology, The University of Western Ontario, London, CanadaDepartment of Epidemiology and Biostatistics, The University of Western Ontario, London, Canada, Children's Health Research Institute, London, Canada, Department of Paediatrics, The University of Western Ontario, London, Canada and Department of Obstetrics and Gynaecology, The University of Western Ontario, London, Canada.
Int J Epidemiol. 2014 Jun;43(3):802-14. doi: 10.1093/ije/dyt251. Epub 2013 Dec 27.
The aim of this study was to elucidate the role of gestational age in determining the risk of neonatal morbidity among infants born late preterm (34-36 weeks) and early term (37-38 weeks) compared with those born full term (39-41 weeks) by examining the contribution of gestational age within the context of biological determinants of preterm birth.
This was a retrospective cohort study. The sample included singleton live births with no major congenital anomalies, delivered at 34-41 weeks of gestation to London-Middlesex (Canada) mothers in 2002-11. Data from a city-wide perinatal database were linked with discharge abstract data. Multivariable models used modified Poisson regression to directly estimate adjusted relative risks (aRRs). The roles of gestational age and biological determinants of preterm birth were further examined using mediation and moderation analyses.
Compared with infants born full term, infants born late preterm and early term were at increased risk for neonatal intensive care unit triage/admission [late preterm aRR=6.14, 95% confidence interval (CI) 5.63, 6.71; early term aRR=1.54, 95% CI 1.41, 1.68] and neonatal respiratory morbidity (late preterm aRR=6.16, 95% CI 5.39, 7.03; early term aRR=1.46, 95% CI 1.29, 1.65). The effect of gestational age was partially explained by biological determinants of preterm birth acting through gestational age. Moreover, placental ischaemia and other hypoxia exacerbated the effect of gestational age on poor outcomes.
Poor outcomes among infants born late preterm and early term are not only due to physiological immaturity but also to biological determinants of preterm birth acting through and with gestational age to produce poor outcomes.
本研究的目的是通过在早产的生物学决定因素背景下考察胎龄的作用，阐明与足月（39 - 41周）出生的婴儿相比，晚期早产（34 - 36周）和早期足月（37 - 38周）出生的婴儿发生新生儿发病风险的情况。
这是一项回顾性队列研究。样本包括2002 - 2011年在加拿大伦敦 - 米德尔塞克斯地区妊娠34 - 41周分娩的无重大先天性异常的单胎活产儿。来自全市围产期数据库的数据与出院摘要数据相链接。多变量模型使用修正泊松回归直接估计调整后的相对风险（aRRs）。使用中介分析和调节分析进一步考察胎龄和早产的生物学决定因素的作用。
与足月出生的婴儿相比，晚期早产和早期足月出生的婴儿进入新生儿重症监护病房进行分诊/住院的风险增加[晚期早产aRR = 6.14，95%置信区间（CI）5.63，6.71；早期足月aRR = 1.54，95% CI 1.41，1.68]以及发生新生儿呼吸系统疾病的风险增加（晚期早产aRR = 6.16，95% CI 5.39，7.03；早期足月aRR = 1.46，95% CI 1.29，1.65）。胎龄的影响部分由通过胎龄起作用的早产生物学决定因素所解释。此外，胎盘缺血和其他缺氧情况加剧了胎龄对不良结局的影响。
晚期早产和早期足月出生的婴儿出现不良结局不仅是由于生理不成熟，还由于早产的生物学决定因素通过胎龄并与胎龄共同作用导致不良结局。
