Carpenter Catherine L, Ross Ronald K, Paganini-Hill Annlia, Bernstein Leslie
Department of Preventive Medicine, USC/Norris Comprehensive Cancer Center, Keck School of Medicine at the University of Southern California, Los Angeles, CA, USA.
Int J Cancer. 2003 Aug 10;106(1):96-102. doi: 10.1002/ijc.11186.
We examined effects of obesity and lifetime exercise patterns on postmenopausal breast cancer risk according to family history in a large population-based case control study conducted in Los Angeles County, California, because we hypothesized that both factors would affect risk through similar mechanistic pathways, and that their effects would be stronger among women with a family history. We studied 1883 postmenopausal breast cancer case subjects and 1628 postmenopausal control subjects ranging in age from 55-72 years. Cases were diagnosed with incident breast cancer in the late 1980s and 1990s. Controls were individually matched to case subjects on age, ethnic origin and neighborhood. In-person interviews determined known breast cancer risk factors including: height, weight, lifetime exercise, and family history of breast and other cancers. Breast cancer risk was raised among women who had at least 1 first-degree relative with breast cancer (odds ratio [OR] = 1.68; 95% confidence interval [CI] = 1.36-2.08). Risk increased with increasing levels of body-mass index (wt-kg/ht-m(2)) (p-trend = 0.005). Breast cancer risk was reduced among women who maintained, on average, 17.6 metabolic equivalent of energy expenditure (MET)-hr of activity/week from menarche onward (OR = 0.66; 95% CI = 0.48-0.90). Body-mass index, adjusted for lifetime exercise, was strongly associated with breast cancer risk among women with a positive family history of breast cancer (p-trend < 0.0001), but only weakly associated among women with no family history (p-trend = 0.08; homogeneity of trends p = 0.0005). In contrast, the risk reduction associated with exercise activity, adjusting for body-mass index, was limited to women without a family history of breast cancer (p-trend = 0.001; homogeneity of trends p = 0.005). Body-mass index and exercise activity, both modifiable risk factors for breast cancer, seem to have differential effects depending on a woman's family history of breast cancer, and may impact risk through different biological mechanisms.
在加利福尼亚州洛杉矶县开展的一项大型基于人群的病例对照研究中，我们根据家族史研究了肥胖和终生运动模式对绝经后乳腺癌风险的影响，因为我们假设这两个因素会通过相似的机制途径影响风险，并且它们在有家族史的女性中影响会更强。我们研究了1883例绝经后乳腺癌病例受试者和1628例年龄在55至72岁之间的绝经后对照受试者。病例是在20世纪80年代末和90年代被诊断为新发乳腺癌的。对照者在年龄、种族和社区方面与病例受试者进行个体匹配。通过面对面访谈确定已知的乳腺癌风险因素，包括：身高、体重、终生运动以及乳腺癌和其他癌症的家族史。有至少1名患乳腺癌的一级亲属的女性患乳腺癌的风险升高（优势比[OR]=1.68；95%置信区间[CI]=1.36 - 2.08）。风险随着体重指数（体重千克/身高米²）水平的升高而增加（p趋势=0.005）。从初潮开始平均每周保持17.6代谢当量能量消耗（MET）-小时活动量的女性患乳腺癌的风险降低（OR = 0.66；95%CI = 0.48 - 0.90）。调整终生运动后的体重指数与有乳腺癌家族史阳性的女性患乳腺癌风险密切相关（p趋势<0.0001），但在无家族史的女性中仅呈弱相关（p趋势=0.08；趋势同质性p = 0.0005）。相反，调整体重指数后与运动活动相关的风险降低仅限于无乳腺癌家族史的女性（p趋势=0.001；趋势同质性p = 0.005）。体重指数和运动活动这两个乳腺癌的可改变风险因素，似乎根据女性的乳腺癌家族史有不同的影响，并且可能通过不同的生物学机制影响风险。
