Yochum Laura, Tamimi Rulla M, Hankinson Susan E
University of Massachusetts Amherst, 426 Arnold House, 716 North Pleasant Street, Amherst, MA, 01003, USA,
Cancer Causes Control. 2014 Oct;25(10):1247-59. doi: 10.1007/s10552-014-0432-0. Epub 2014 Jul 23.
To evaluate the association between birth weight and early life body size with adult mammographic density in the peer-reviewed literature.
A comprehensive literature search was conducted through January, 2014. English language articles that assessed adult mammographic density (MD) in relation to early life body size (≤18 years old), or birthweight were included.
Nine studies reported results for early life body size and %MD. Both exposure and outcome were assessed at different ages using multiple methods. In premenopausal women, findings were inconsistent; two studies reported significant, inverse associations, one reported a non-significant, inverse association, and two observed no association. Reasons for these inconsistencies were not obvious. In postmenopausal women, four of five studies supported an inverse association. Two of three studies that adjusted for menopausal status found significant, inverse associations. Birthweight and %MD was evaluated in nine studies. No association was seen in premenopausal women and two of three studies reported positive associations in postmenopausal women. Three of four studies that adjusted for menopausal status found no association.
Early life body size and birthweight appear unrelated to %MD in premenopausal women while an inverse association in postmenopausal women is more likely. Although based on limited data, birthweight and %MD appear positively associated in postmenopausal women. Given the small number of studies, the multiple methods of data collection and analysis, other methodologic issues, and lack of consistency in results, additional research is needed to clarify this complex association and develop a better understanding of the underlying biologic mechanisms.
在同行评审文献中评估出生体重和儿童早期身体大小与成年女性乳腺X线密度之间的关联。
截至2014年1月进行了全面的文献检索。纳入了评估成年女性乳腺X线密度（MD）与儿童早期身体大小（≤18岁）或出生体重关系的英文文章。
九项研究报告了儿童早期身体大小和MD百分比的结果。暴露因素和结局均采用多种方法在不同年龄进行评估。在绝经前女性中，研究结果不一致；两项研究报告了显著的负相关，一项报告了不显著的负相关，两项研究未观察到相关性。这些不一致的原因并不明显。在绝经后女性中，五项研究中有四项支持负相关。三项对绝经状态进行调整后的研究中有两项发现了显著的负相关。九项研究评估了出生体重与MD百分比的关系。绝经前女性未发现相关性，三项研究中有两项报告绝经后女性存在正相关。四项对绝经状态进行调整后的研究中有三项未发现相关性。
儿童早期身体大小和出生体重与绝经前女性的MD百分比似乎无关，而绝经后女性更可能存在负相关。尽管基于有限的数据，但出生体重与绝经后女性的MD百分比似乎呈正相关。鉴于研究数量较少、数据收集和分析方法多样、存在其他方法学问题以及结果缺乏一致性，需要进一步研究以阐明这种复杂的关联，并更好地理解潜在的生物学机制。
