Department of Medical Education, China Medical University Hospital, Taichung, Taiwan; Institute of Medicine, School of Medicine, Chung Shan Medical University, Taichung, Taiwan.
Institute of Medicine, School of Medicine, Chung Shan Medical University, Taichung, Taiwan; Division of Allergy, Immunology and Rheumatology, Chung Shan Medical University Hospital, Taichung, Taiwan; Graduate Institute of Integrated Medicine, China Medical University, Taichung, Taiwan.
Endocr Pract. 2021 Apr;27(4):298-305. doi: 10.1016/j.eprac.2020.09.007. Epub 2020 Dec 15.
The results of studies investigating the relationship between breast cancer and hypothyroidism vary greatly from study to study. In this study, we analyzed a large and reliable, population-based database to gain a better understanding of the correlation.
This retrospective cohort study analyzed patients with hypothyroidism between January 1, 2000 and December 31, 2012 (hypothyroidism cohort) from the Longitudinal Health Insurance Database 2000 in Taiwan. For each woman with hypothyroidism, 1 woman without a history of breast cancer was randomly selected from the Longitudinal Health Insurance Database 2000 and frequency matched (1:4) with women without hypothyroidism by age and index year of hypothyroidism. The study outcome was the diagnosis of breast cancer during a 12-year follow-up period.
In this study, 6665 women with hypothyroidism and 26 660 women without hypothyroidism were identified. The hypothyroidism cohort had a significantly higher risk of breast cancer than the nonhypothyroidism cohort (adjusted hazard ratio [aHR] 1.69 [95% CI, 1.15-2.49]; P = .01), especially in the group aged 40 to 64 years (aHR 2.07 [95% CI, 1.32-3.23]; P = .01). Women in the hypothyroidism cohort taking levothyroxine for a duration ˃588 days showed a significantly decreased risk of breast cancer (aHR 0.37 [95% CI, 0.19-0.71]; P = .003).
Women with hypothyroidism are at a higher risk of breast cancer than those without hypothyroidism. Levothyroxine may reduce the risk of breast cancer in a woman with hypothyroidism.
研究乳腺癌与甲状腺功能减退症之间关系的各项研究结果差异极大。本研究通过分析一个大型可靠的基于人群的数据库，以更好地了解两者之间的相关性。
本回顾性队列研究分析了 2000 年 1 月 1 日至 2012 年 12 月 31 日期间（甲状腺功能减退症队列）来自台湾纵向健康保险数据库 2000 年的甲状腺功能减退症患者。对于每一位患有甲状腺功能减退症的女性，从纵向健康保险数据库 2000 年中随机选择一位无乳腺癌病史的女性，并按年龄和甲状腺功能减退症索引年与无甲状腺功能减退症的女性进行频率匹配（1:4）。研究结果为 12 年随访期间乳腺癌的诊断。
本研究共纳入 6665 例甲状腺功能减退症女性和 26660 例无甲状腺功能减退症女性。甲状腺功能减退症组的乳腺癌发病风险明显高于无甲状腺功能减退症组（校正后风险比 [aHR] 1.69 [95%置信区间，1.15-2.49]；P =.01），尤其是年龄在 40 至 64 岁的患者（aHR 2.07 [95%置信区间，1.32-3.23]；P =.01）。甲状腺功能减退症组中接受左甲状腺素治疗时间>588 天的女性，乳腺癌发病风险显著降低（aHR 0.37 [95%置信区间，0.19-0.71]；P =.003）。
与无甲状腺功能减退症的女性相比，甲状腺功能减退症女性患乳腺癌的风险更高。左甲状腺素可能会降低甲状腺功能减退症女性患乳腺癌的风险。
