Division of Cancer Epidemiology and Genetics, National Cancer Institute, 6120 Executive Boulevard, Bethesda, MD 20892, USA.
Br J Cancer. 2010 Sep 28;103(7):933-8. doi: 10.1038/sj.bjc.6605902.
Physical activity has been hypothesised to reduce endometrial cancer risk, but this relationship has been difficult to confirm because of a limited number of prospective studies. However, recent publications from five cohort studies, which together comprise 2663 out of 3463 cases in the published literature for analyses of recreational physical activity, may help resolve this question. To synthesise these new data, we conducted a meta-analysis of prospective studies published through to December 2009. We found that physical activity was clearly associated with reduced risk of endometrial cancer, with active women having an approximately 30% lower risk than inactive women. Owing to recent interest in sedentary behaviour, we further investigated sitting time in relation to endometrial cancer risk using data from the NIH-AARP Diet and Health Study. We found that, independent of the level of moderate-vigorous physical activity, greater sitting time was associated with increased endometrial cancer risk. Thus, limiting time in sedentary behaviours may complement increasing level of moderate-vigorous physical activity as a means of reducing endometrial cancer risk. Taken together with the established biological plausibility of this relation, the totality of evidence now convincingly indicates that physical activity prevents or reduces risk of endometrial cancer.
体力活动被假设可以降低子宫内膜癌的风险，但由于前瞻性研究的数量有限，这一关系一直难以确认。然而，最近来自五项队列研究的出版物，这些研究共同包含了已发表文献中 2663 例子宫内膜癌病例中的 3463 例，用于分析休闲体力活动，可能有助于解决这个问题。为了综合这些新数据，我们对截至 2009 年 12 月发表的前瞻性研究进行了荟萃分析。我们发现体力活动与子宫内膜癌风险降低明显相关，与不活跃的女性相比，活跃的女性风险降低约 30%。由于最近对久坐行为的兴趣，我们使用 NIH-AARP 饮食与健康研究的数据进一步调查了与子宫内膜癌风险相关的久坐时间。我们发现，独立于中-高强度体力活动的水平，久坐时间的增加与子宫内膜癌风险的增加相关。因此，限制久坐行为的时间可能与增加中-高强度体力活动相结合，作为降低子宫内膜癌风险的一种手段。综合考虑这一关系的既定生物学合理性，目前所有证据都令人信服地表明体力活动可以预防或降低子宫内膜癌的风险。
