Epidemiology and Prevention Division, Research Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan.
Int J Cancer. 2011 Sep 1;129(5):1214-24. doi: 10.1002/ijc.25744. Epub 2011 Apr 8.
Few prospective studies have investigated the association between BMI at age 20 years (BMI20y) and breast cancer risk with consideration to estrogen/progesterone receptor status (ER/PR). We evaluated the association between BMI20y and ER/PR-defined breast cancer risk among 41,594 women in the population-based Japan Public Health Center-based Prospective Study. Anthropometric factors were assessed using self-reported questionnaires. Relative risks (RRs) were estimated by Cox proportional hazards regression models. Through to the end of 2006, 452 breast cancer cases were identified. We observed a statistically significant inverse association between BMI20y and breast cancer incidence [multivariable-adjusted RR for each 5-unit increment 0.75 (95%CI=0.61-0.92)], which was not modified by menopausal or recent BMI status. In contrast, recent BMI and subsequent BMI gain were not associated with increased risk among premenopausal women, but were substantially associated with increased risk among postmenopausal women [corresponding RR(recent BMI)=1.31 (95%CI=1.07-1.59); RR(subsequent BMI gain)=1.32 (95%CI=1.09-1.60)]. In subanalyses by receptor status (∼50% of cases), the observed inverse association of BMI20y with risk was consistent with the result for ER-PR- [0.49 (95%CI=0.27-0.88)], while the observed positive associations of BMI gain with postmenopausal breast cancer risk appeared to be confined to ER+PR+ tumors [corresponding RR(for subsequent BMI gain)=2.24 (95%CI=1.50-3.34)]. Low BMI at age 20 years was substantially associated with an increased risk of breast cancer. In contrast, high recent BMI and subsequent BMI gain from age 20 were associated with increased risk of postmenopausal ER+PR+ tumors.
很少有前瞻性研究调查过 20 岁时的 BMI（BMI20y）与乳腺癌风险之间的关系，并考虑了雌激素/孕激素受体状态（ER/PR）。我们评估了在基于人群的日本公共卫生中心前瞻性研究中，41594 名女性中 BMI20y 与 ER/PR 定义的乳腺癌风险之间的关联。人体测量因素使用自我报告的问卷进行评估。相对风险（RR）通过 Cox 比例风险回归模型进行估计。截至 2006 年底，共发现 452 例乳腺癌病例。我们观察到 BMI20y 与乳腺癌发病率之间存在统计学上显著的反比关系[每个 5 个单位增加的多变量调整 RR 为 0.75（95%CI=0.61-0.92）]，而绝经状态或近期 BMI 状态并未改变这一关系。相比之下，近期 BMI 和随后的 BMI 增加与绝经前女性的风险增加无关，但与绝经后女性的风险增加密切相关[对应 RR（近期 BMI）=1.31（95%CI=1.07-1.59）；RR（随后 BMI 增加）=1.32（95%CI=1.09-1.60）]。根据受体状态进行的亚分析（约 50%的病例），BMI20y 与风险之间观察到的反比关系与 ER-PR-一致[0.49（95%CI=0.27-0.88）]，而 BMI 增加与绝经后乳腺癌风险之间观察到的正相关似乎仅限于 ER+PR+肿瘤[对应 RR（随后 BMI 增加）=2.24（95%CI=1.50-3.34）]。20 岁时的低 BMI 与乳腺癌风险增加密切相关。相比之下，较高的近期 BMI 和 20 岁以后的 BMI 增加与绝经后 ER+PR+肿瘤的风险增加有关。
