Gaudet Mia M, Carter Brian D, Patel Alpa V, Teras Lauren R, Jacobs Eric J, Gapstur Susan M
Epidemiology Research Program, American Cancer Society, 250 Williams Street NW, Atlanta, GA, 30303, USA,
Cancer Causes Control. 2014 Jun;25(6):737-45. doi: 10.1007/s10552-014-0376-4. Epub 2014 Apr 9.
High body mass index (BMI) is an established risk factor for postmenopausal breast cancer. However, less is known about associations with waist circumference. In particular, it is unclear whether a larger waist circumference is associated with risk more than would be expected based solely on its contribution to BMI.
We examined the associations of BMI and waist circumference with risk of postmenopausal breast cancer, with and without mutual adjustment, in the Cancer Prevention Study-II Nutrition Cohort. Analyses included 28,965 postmenopausal women who reported weight and waist circumference on a questionnaire in 1997 and were not taking menopausal hormones.
During a median follow-up of 11.58 years, 1,088 invasive breast cancer cases were identified. Hazard ratios (HR) and 95 % confidence intervals (CI) were estimated from multivariable-adjusted Cox proportional hazard regression models. Without adjustment for BMI, a larger waist circumference was associated with higher risk of breast cancer (per 10 cm increase in waist circumference, HR = 1.13, 95 % CI 1.08-1.19). However, adjustment for BMI eliminated the association with waist circumference (per 10 cm HR = 1.00, 95 % CI 0.92-1.08). BMI was associated with risk unadjusted for waist circumference (per 1 kg/m(2) HR = 1.04, 95 % CI 1.03-1.05) and adjusted for waist circumference (per 1 kg/m(2) HR = 1.04, 95 % CI 1.02-1.06).
Our study of predominantly white women provides evidence that a larger waist circumference is associated with higher risk of postmenopausal breast cancer, but not beyond its contribution to BMI.
高体重指数（BMI）是绝经后乳腺癌的既定风险因素。然而，关于其与腰围的关联了解较少。特别是，目前尚不清楚腰围较大与风险的关联是否超过仅基于其对BMI的影响所预期的程度。
在癌症预防研究-II营养队列中，我们研究了BMI和腰围与绝经后乳腺癌风险的关联，包括相互调整和未调整的情况。分析纳入了28965名绝经后女性，她们在1997年通过问卷报告了体重和腰围，且未服用绝经激素。
在中位随访11.58年期间，共确定了1088例浸润性乳腺癌病例。通过多变量调整的Cox比例风险回归模型估计风险比（HR）和95%置信区间（CI）。在未调整BMI的情况下，腰围较大与乳腺癌风险较高相关（腰围每增加10 cm，HR = 1.13，95% CI 1.08 - 1.19）。然而，调整BMI后消除了腰围与风险的关联（腰围每增加10 cm，HR = 1.00，95% CI 0.92 - 1.08）。BMI在未调整腰围时与风险相关（每1 kg/m²，HR = 1.04，95% CI 1.03 - 1.05），在调整腰围后也与风险相关（每1 kg/m²，HR = 1.04，95% CI 1.02 - 1.06）。
我们对主要为白人女性的研究表明，腰围较大与绝经后乳腺癌风险较高相关，但不超过其对BMI的影响。
