Seasonal Changes of Thyroid Function Parameters in Women of Reproductive Age Between 2012 and 2018: A Retrospective, Observational, Single-Center Study

作者：Jinrong Fu, Guofeng Zhang, Pei Xu, Rui Guo, Jiarong Li, Haixia Guan, Yushu Li · 发表于：Frontiers in Endocrinology · 年份：2021 · DOI：10.3389/fendo.2021.719225 · 被引用次数：21 · 研究领域：Thyroid Disorders and Treatments、Birth, Development, and Health、Thyroid Cancer Diagnosis and Treatment

Background Thyroid function can be influenced by external stimuli such as light and temperature. However, it is currently unknown whether there is seasonal variation of thyroid function in women of reproductive age. Adequate thyroid function in reproductive-aged women is necessary for optimal fetal–maternal outcomes. Therefore, this study aims to evaluate the seasonal changes in levels of thyrotropin (TSH), free triiodothyronine (FT 3 ), free thyroxine (FT 4 ), and TSH index (TSHI) in women of reproductive age. Methods A large retrospective study was conducted that included women aged 20–49 years who visited our outpatient or checkup center between 2012 and 2018. Thyroid function was measured using the automated immunochemiluminescent assay kit. Subjects with overt thyroid dysfunction, pregnancy, thyroid disease, cancer, and severe infectious or psychological disease were excluded. Seasonal differences of thyroid function were analyzed using the Kruskal–Wallis test or the analysis of means with transformed ranks. Spearman’s correlation was performed to evaluate the association between thyroid function parameters and age. A subset of 181 subjects was included in the longitudinal analyses. Differences in thyroid function between summer and winter were analyzed using the Wilcoxon signed-rank test. Results A total of 48,990 women with a median age of 39 years were included. The prevalence of subclinical hypothyroidism was lower in summer but higher in winter (5.6% vs. 7.0%, p &am...