Introduction Obesity is a risk factor for both the development of and mortality from breast cancer in postmenopausal but not in premenopausal women. However, which part of the fat mass is associated with risk remains unclear, and whether the difference in the risk for breast cancer is associated with discrepancy in the distribution of fat with menstrual status requires further study. Methods A dataset from the UK Biobank, which included 245,009 female participants, and 5402 females who developed breast cancer during a mean follow-up of 6.6 years was analyzed. Body fat mass was measured according to bioelectrical impedance at baseline by trained technicians. Age- and multivariable-adjusted hazard ratios and corresponding 95% confidence intervals for associations between body fat distribution and the risk for breast cancer were estimated using Cox proportional hazards regression. Height, age, education level, ethnicity, index of multiple deprivation, alcohol intake, smoking, physical activity, fruit consumption, age at menarche, age at first birth, number of births, hormone replacement therapy, family history of breast cancer, hysterectomy, and ovariotomy were adjusted for potential confounders. Results Fat distribution differed between pre- and postmenopausal women. After menopause, there was an increase in fat mass in different body segments (arms, legs, and trunk). After age- and multivariable-adjustment, fat mass in different segments, BMI, and waist circumference were significantly associated with the risk for breast cancer among postmenopausal but not premenopausal women. Conclusion Postmenopausal women exhibited more fat in different body segments, which are associated with increased risk for breast cancer, compared to premenopausal women. Fat mass control throughout the body may be beneficial in mitigating the risk for breast cancer and was not limited to abdominal fat alone among postmenopausal women.


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绝经前和绝经后女性身体脂肪分布与乳腺癌风险的关系

简介 肥胖是绝经后女性乳腺癌发生和死亡的危险因素，但绝经前女性则不然。然而，哪一部分脂肪量与风险相关尚不清楚，乳腺癌风险的差异是否与月经状态下脂肪分布的差异有关，还需要进一步研究。方法 对英国生物银行的数据集进行了分析，其中包括 245,009 名女性参与者，以及 5402 名在平均 6.6 年随访期间患乳腺癌的女性。由训练有素的技术人员根据基线生物电阻抗测量体脂肪量。使用 Cox 比例风险回归估计年龄和多变量调整后的风险比以及身体脂肪分布与乳腺癌风险之间关联的相应 95% 置信区间。身高、年龄、教育水平、种族、多重剥夺指数、饮酒量、吸烟、体力活动、水果摄入量、初潮年龄、初产年龄、出生次数、激素替代疗法、乳腺癌家族史、子宫切除术、和卵巢切除术针对潜在的混杂因素进行了调整。结果绝经前和绝经后女性的脂肪分布不同。更年期后，身体不同部位（手臂、腿和躯干）的脂肪量增加。经过年龄和多变量调整后，不同部位的脂肪量、BMI和腰围与绝经后女性乳腺癌风险显着相关，但与绝经前女性乳腺癌风险无关。结论 与绝经前女性相比，绝经后女性在不同身体部位表现出更多的脂肪，这与乳腺癌风险增加相关。控制全身的脂肪量可能有助于降低患乳腺癌的风险，并且不仅仅限于绝经后女性的腹部脂肪。