CancerCare Manitoba, 675 McDermot, Avenue, Winnipeg, MB R3E 0V9, Canada.
Breast Cancer Res Treat. 2011 Apr;126(3):679-86. doi: 10.1007/s10549-010-1138-y. Epub 2010 Sep 14.
To determine if higher bone mineral density (BMD) is a risk factor for breast cancer in women age 50 years and older. 37,860 women ≥ 50-year old with no previous breast cancer diagnosis had baseline BMD assessment between January 1999 and December 2007. Cox proportional hazards models were created for time to a new breast cancer as a function of lumbar spine or femoral neck BMD quartile (1st = lowest as reference) with adjustment for relevant covariates. A secondary analysis was performed to look for an association with estrogen receptor-positive (ER-positive) breast cancers. 794 invasive and in situ breast cancers (484 ER-positive) occurred with a median follow up of 5.4 years. Increased breast cancer risk was seen for the 3rd and 4th quartiles of lumbar spine BMD with hazard ratios (HRs) of 1.26 (95% CI, 1.01-1.58) and 1.45 (95% CI, 1.16-1.81), respectively and for the 3rd quartile of femoral neck BMD with a HR of 1.33 (95% CI, 1.07-1.64). A test for linear trend showed that lumbar spine BMD (P < 0.001) and femoral neck BMD (P = 0.04) were associated with increased risk. Higher lumbar spine BMD was also associated with increased risk of ER-positive breast cancer with HR of 1.45 (95% CI, 1.08-1.94), and 1.68 (95% CI, 1.24-2.27) for women in the 2nd and 4th quartiles, respectively. A test for linear trend showed lumbar spine BMD was associated with increasing risk of ER-positive breast cancer (P = 0.003). Increased ER-positive breast cancer risk was seen for the 3rd quartile of femoral neck BMD with a HR of 1.43 (95% CI, 1.08-1.89). Higher lumbar spine and femoral neck BMD are associated with higher risk of breast cancer in women ≥50-year old. Lumbar spine and femoral neck BMD are associated with increased risk of ER-positive breast cancer.
为了确定骨密度（BMD）较高是否是 50 岁及以上女性乳腺癌的危险因素。1999 年 1 月至 2007 年 12 月期间，对 37860 名无乳腺癌既往病史的 50 岁以上女性进行了基线 BMD 评估。建立了新乳腺癌发病时间的 Cox 比例风险模型，作为腰椎或股骨颈 BMD 四分位（第 1 四分位为最低参考）的函数，调整了相关协变量。进行了二次分析以寻找与雌激素受体阳性（ER 阳性）乳腺癌的关联。中位随访 5.4 年后，发生 794 例浸润性和原位乳腺癌（484 例 ER 阳性）。腰椎 BMD 的第 3 四分位和第 4 四分位的乳腺癌风险增加，风险比（HR）分别为 1.26（95%CI，1.01-1.58）和 1.45（95%CI，1.16-1.81），而股骨颈 BMD 的第 3 四分位 HR 为 1.33（95%CI，1.07-1.64）。线性趋势检验显示，腰椎 BMD（P<0.001）和股骨颈 BMD（P=0.04）与风险增加相关。腰椎 BMD 较高也与 ER 阳性乳腺癌风险增加相关，第 2 四分位和第 4 四分位的 HR 分别为 1.45（95%CI，1.08-1.94）和 1.68（95%CI，1.24-2.27）。线性趋势检验显示，腰椎 BMD 与 ER 阳性乳腺癌风险增加相关（P=0.003）。股骨颈 BMD 的第 3 四分位 HR 为 1.43（95%CI，1.08-1.89），与 ER 阳性乳腺癌风险增加相关。50 岁及以上女性腰椎和股骨颈 BMD 较高与乳腺癌风险增加相关。腰椎和股骨颈 BMD 与 ER 阳性乳腺癌的风险增加相关。
