1 Department of Epidemiology, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina.
2 Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina.
J Womens Health (Larchmt). 2018 Mar;27(3):377-386. doi: 10.1089/jwh.2016.6063. Epub 2017 Jun 1.
The use of combined estrogen-progestin menopausal hormone therapy (MHT) has been shown to increase the risk of breast cancer, however, recent observational studies have suggested that the association between MHT and breast cancer may be modified by race. The objective of this study was to investigate the association between MHT use and incidence of invasive breast cancer in Black and White women aged ≥40 years at diagnosis after accounting for racial differences in patterns of MHT use and formulation.
Data from the Carolina Breast Cancer Study, a population-based case-control study of Black and White women in North Carolina conducted between 1993 and 2001, was used to analyze 1474 invasive breast cancer cases and 1339 controls using unconditional logistic regression.
Black women were less likely than White women to use any MHT and were more likely to use an unopposed-estrogen formulation. Combined estrogen-progestin MHT use was associated with a greater odds of breast cancer in White (adjusted odds ratio [OR] 1.48, 95% confidence interval [CI]: 1.03-2.13) and Black (OR 1.43, 95% CI: 0.76-2.70) women, although the estimate in Black women was imprecise. In contrast, use of unopposed-estrogen MHT among women with prior hysterectomy was not associated with breast cancer in women of either race.
The association between MHT and invasive breast cancer appears to be similar in both Black and White women after accounting for differences in formulation and prior hysterectomy. These findings emphasize the importance of accounting for MHT formulation in race-stratified analyses of breast cancer risk.
联合使用雌激素-孕激素的绝经激素治疗（MHT）已被证实会增加乳腺癌的风险，然而，最近的观察性研究表明，MHT 与乳腺癌之间的关联可能因种族而异。本研究旨在调查在考虑到 MHT 使用模式和配方的种族差异后，MHT 使用与黑人及白人女性诊断后≥40 岁时浸润性乳腺癌发病之间的关联。
本研究使用了 1993 年至 2001 年间在北卡罗来纳州进行的一项基于人群的黑人及白人女性病例对照研究——卡罗来纳乳腺癌研究的数据，采用非条件逻辑回归分析了 1474 例浸润性乳腺癌病例和 1339 例对照。
与白人女性相比，黑人女性使用任何 MHT 的可能性更低，且更倾向于使用未加孕激素的雌激素配方。白人（调整后的比值比 [OR] 1.48，95%置信区间 [CI]：1.03-2.13）和黑人（OR 1.43，95% CI：0.76-2.70）女性使用联合雌激素-孕激素 MHT 与乳腺癌的发生风险增加相关，尽管黑人女性的估计值不够精确。相比之下，对于已行子宫切除术的女性，使用未加孕激素的雌激素 MHT 与两种族女性的乳腺癌均无关联。
在考虑到配方和子宫切除术的差异后，MHT 与浸润性乳腺癌之间的关联在黑人和白人女性中似乎相似。这些发现强调了在按种族分层分析乳腺癌风险时考虑 MHT 配方的重要性。
