Huxley Rachel, Owen Christopher G, Whincup Peter H, Cook Derek G, Rich-Edwards Janet, Smith George Davey, Collins Rory
George Institute, University of Sydney, Sydney, Australia.
Am J Clin Nutr. 2007 May;85(5):1244-50. doi: 10.1093/ajcn/85.5.1244.
An inverse association between birth weight and ischemic heart disease (IHD) has been seen in observational studies.
We wanted to determine the strength and consistency of the association between birth weight and subsequent IHD.
We conducted a systematic review of observational studies.
Seventeen published studies of birth weight and subsequent IHD were identified that included a total of 144,794 singletons. Relative risk estimates for the association between birth weight and IHD were available from 16 of these studies. Additional data from 2 unpublished studies of 3801 persons were also included. In total, the analyses included data from 18 studies on 4210 nonfatal and 3308 fatal IHD events in 147,009 persons. The mean weighted estimate for the association between birth weight and the combined outcome of nonfatal and fatal IHD was 0.84 (95% CI: 0.81, 0.88) per kilogram of birth weight (P<0.0001). No significant heterogeneity was observed between estimates in different studies (P=0.09), nor was there evidence of publication bias (P=0.3, Begg test). Neither restricting the analysis to fatal IHD events nor adjusting for socioeconomic status had any appreciable effect on the findings.
These findings are consistent with a 1 kg higher birth weight being associated with a 10-20% lower risk of subsequent IHD. However, even if causal, interventions to increase birth weight are unlikely to reduce the incidence of IHD materially. Further studies are needed to determine whether the observed association reflects a stronger underlying association with a related exposure or is due (at least in part) to residual confounding.
观察性研究发现出生体重与缺血性心脏病（IHD）之间存在负相关。
我们想要确定出生体重与后续缺血性心脏病之间关联的强度和一致性。
我们对观察性研究进行了系统综述。
共确定了17项已发表的关于出生体重与后续缺血性心脏病的研究，其中包括144,794名单胎婴儿。这些研究中有16项提供了出生体重与缺血性心脏病关联的相对风险估计值。另外还纳入了2项未发表研究中的3801人的数据。总计，分析纳入了18项研究中147,009人发生的4210例非致命性和3308例致命性缺血性心脏病事件的数据。出生体重与非致命性和致命性缺血性心脏病综合结局之间关联的平均加权估计值为每千克出生体重0.84（95%可信区间：0.81, 0.88）（P<0.0001）。不同研究的估计值之间未观察到显著异质性（P=0.09），也没有证据表明存在发表偏倚（P=0.3，Begg检验）。将分析局限于致命性缺血性心脏病事件或对社会经济地位进行调整，均未对研究结果产生明显影响。
这些发现与出生体重每增加1千克，后续缺血性心脏病风险降低10%-20%相一致。然而，即使存在因果关系，增加出生体重的干预措施也不太可能实质性降低缺血性心脏病的发病率。需要进一步研究以确定观察到的关联是反映了与相关暴露更强的潜在关联，还是（至少部分）由于残余混杂因素所致。
