Moylan Steven, Gustavson Kristin, Øverland Simon, Karevold Evalill Bølstad, Jacka Felice N, Pasco Julie A, Berk Michael
School of Medicine, Deakin University, Geelong 3220, Victoria, Australia.
BMC Med. 2015 Feb 3;13:24. doi: 10.1186/s12916-014-0257-4.
Maternal smoking during pregnancy (MSDP) is associated with multiple adverse childhood outcomes including externalizing behaviors. However, the association between MSDP and internalizing (anxiety and depressive) behaviors in offspring has received less investigation. We aimed to assess the association between MSDP and childhood internalizing (anxiety and depressive) behaviors in a very large, well-characterized cohort study.
We assessed the association between MSDP and internalizing behaviors in offspring utilizing information drawn from 90,040 mother-child pairs enrolled in the Norwegian Mother and Child Cohort Study. Mothers reported smoking information, including status and frequency of smoking, twice during pregnancy. Mothers also reported their child's internalizing behaviors at 18 months, 36 months, and 5 years. Associations between MSDP and childhood internalizing behaviors, including dose-response and timing of smoking in pregnancy, were assessed at each time point.
MSDP was associated with increased internalizing behaviors when offspring were aged 18 months (B = 0.11, P <0.001) and 36 months (B = 0.06, P <0.01), adjusting for numerous potential confounders. Higher rates of smoking (e.g., >20 cigarettes per day) were associated with higher levels of internalizing behaviors. Maternal smoking during early pregnancy appeared to be the critical period for exposure.
We found evidence supporting a potential role for MSDP in increasing internalizing (anxiety and depressive) behaviors in offspring. We also found evidence supportive of a possible causal relationship, including dose-dependency and support for a predominant role of early pregnancy exposure. Further investigation utilizing genetically informed designs are warranted to assess this association.
孕期母亲吸烟（MSDP）与多种不良儿童结局相关，包括外化行为。然而，MSDP与后代内化（焦虑和抑郁）行为之间的关联研究较少。我们旨在通过一项规模非常大、特征明确的队列研究，评估MSDP与儿童内化（焦虑和抑郁）行为之间的关联。
我们利用挪威母婴队列研究中90,040对母婴的数据，评估MSDP与后代内化行为之间的关联。母亲在孕期报告了两次吸烟信息，包括吸烟状况和频率。母亲还报告了孩子在18个月、36个月和5岁时的内化行为。在每个时间点评估MSDP与儿童内化行为之间的关联，包括剂量反应和孕期吸烟时间。
在调整了众多潜在混杂因素后，当后代18个月大时（B = 0.11，P <0.001）和36个月大时（B = 0.06，P <0.01），MSDP与内化行为增加相关。较高的吸烟率（例如，每天>20支香烟）与较高水平的内化行为相关。孕早期母亲吸烟似乎是暴露的关键时期。
我们发现有证据支持MSDP在增加后代内化（焦虑和抑郁）行为方面可能发挥的作用。我们还发现有证据支持可能存在因果关系，包括剂量依赖性以及支持孕早期暴露起主要作用。有必要利用基因信息设计进行进一步研究来评估这种关联。
