Dah-Ching Ding1,2, Weishan Chen3,4, Jen-Hung Wang5, Shinn-Zong Lin6, Fung-Chang Sung3,7. 1. Department of Obstetrics and Gynecology, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Tzu Chi University, Hualien, Taiwan. 2. Institute of Medical Sciences, Tzu Chi University, Hualien, Taiwan. 3. Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan. 4. College of Medicine, China Medical University, Taichung, Taiwan. 5. Department of Research, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Tzu Chi University, Hualien, Taiwan. 6. Department of Neurosurgery, Hualien Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, Tzu Chi University, Hualien, Taiwan. 7. Department of Health Services Administration, China Medical University College of Public Health, Taichung, Taiwan.
Abstract
BACKGROUND: The current study evaluated whether the risk of developing thyroid cancer in Asian women was associated with infertility and the use of fertility drugs. METHODS: The authors conducted a large, retrospective cohort study using Taiwan's National Health Insurance Research Database. From the insurance claims data, a total of 13,356 women aged 20 to 49 years who were diagnosed with infertility from 2000 through 2013 were included in the infertile group, and 53,424 women without a history of infertility were selected as fertile comparisons and were frequency matched by age and year of diagnosis. Both groups were followed up to 2013 to calculate incident thyroid cancer. Poisson regression analysis was used to estimate the incidence rate ratio (IRR). RESULTS: The incidence of thyroid cancer was 1.9-fold greater in the infertile group compared with the comparison group (2.85 vs 1.53 per 10,000 person-years), with an adjusted IRR of 1.80 (95% confidence interval [95% CI], 1.70-1.92) for the infertile group. Higher cancer incidence was demonstrated for the infertile group after 7 years of follow-up, with an adjusted IRR of 4.39 (95% CI, 4.03-4.78) compared with the comparison group. Among infertile women, those who had taken the fertility drug clomiphene were found to have a reduced incidence of thyroid cancer compared with those who were treated without the drug (2.69 vs 3.42 per 10,000 person-years), with an adjusted IRR of 0.86 (95% CI, 0.75-0.99). However, the cancer incidence in infertile women being treated with clomiphene was nearly 6-fold greater than that in fertile women taking the drug. CONCLUSIONS: The results of the current study provide evidence that women with infertility are at an increased risk of developing thyroid cancer.
BACKGROUND: The current study evaluated whether the risk of developing thyroid cancer in Asian women was associated with infertility and the use of fertility drugs. METHODS: The authors conducted a large, retrospective cohort study using Taiwan's National Health Insurance Research Database. From the insurance claims data, a total of 13,356 women aged 20 to 49 years who were diagnosed with infertility from 2000 through 2013 were included in the infertile group, and 53,424 women without a history of infertility were selected as fertile comparisons and were frequency matched by age and year of diagnosis. Both groups were followed up to 2013 to calculate incident thyroid cancer. Poisson regression analysis was used to estimate the incidence rate ratio (IRR). RESULTS: The incidence of thyroid cancer was 1.9-fold greater in the infertile group compared with the comparison group (2.85 vs 1.53 per 10,000 person-years), with an adjusted IRR of 1.80 (95% confidence interval [95% CI], 1.70-1.92) for the infertile group. Higher cancer incidence was demonstrated for the infertile group after 7 years of follow-up, with an adjusted IRR of 4.39 (95% CI, 4.03-4.78) compared with the comparison group. Among infertilewomen, those who had taken the fertility drug clomiphene were found to have a reduced incidence of thyroid cancer compared with those who were treated without the drug (2.69 vs 3.42 per 10,000 person-years), with an adjusted IRR of 0.86 (95% CI, 0.75-0.99). However, the cancer incidence in infertilewomen being treated with clomiphene was nearly 6-fold greater than that in fertile women taking the drug. CONCLUSIONS: The results of the current study provide evidence that women with infertility are at an increased risk of developing thyroid cancer.
Authors: Zhongqin Gong; Shucai Yang; Minghui Wei; Alexander C Vlantis; Jason Y K Chan; C Andrew van Hasselt; Dongcai Li; Xianhai Zeng; Lingbin Xue; Michael C F Tong; George G Chen Journal: Front Oncol Date: 2022-06-24 Impact factor: 5.738
Authors: Jan Jiskra; Jiří Horáček; Sylvie Špitálníková; Jan Paleček; Zdeňka Límanová; Jan Krátký; Drahomíra Springer; Kristýna Žabková; Hana Vítková Journal: Eur Thyroid J Date: 2022-02-28