Circadian and Circannual Rhythms in Thyroid Hormones: Determining the TSH and Free T4 Reference Intervals Based Upon Time of Day, Age, and Sex
Circadian and Circannual Rhythms in Thyroid Hormones: Determining the TSH and Free T4 Reference Intervals Based Upon Time of Day, Age, and Sex
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DOI：
10.1089/thy.2014.0589
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发表时间：
2015-08-01
期刊：
影响因子：
6.6
通讯作者：
Benvenga, Salvatore
中科院分区：
文献类型：
--
作者：
Ehrenkranz, Joel;Bach, Phillip R.;Benvenga, Salvatore
背景资料：建立促甲状腺激素（TSH）和游离甲状腺素（T4）的参考区间具有临床重要性，因为许多疾病状态与TSH和游离T4浓度的变化有关，这些变化在正常甲状腺激素值的95%置信区间内。已知年龄、性别、一天中的时间和种族会影响TSH和游离T4的循环水平，但尚未用于建立参考区间。本研究的目的是确定参考区间TSH和游离T4考虑到年龄，性别，种族，昼夜节律和circannual variability.Methods：我们进行了回顾性分析465,593 TSH和112,994游离T4测量受试者年龄1-104岁，没有甲状腺疾病，使用一个单一的TSH和游离T4免疫测定方法。边界为中心的95%的患者值，考虑到小时的一天，一年中的一天，性别和年龄counted.Results：女性有显着较高的TSH和游离T4水平比男性，这些差异的幅度不超过0.1 mIU/L或0.1 ng/dL。虽然2.5% TSH参考区间在不同的日期和年龄范围内保持不变，但TSH参考区间的上限（97.5%）随着年龄的增长从6.45 mIU/L增加到7.55 mIU/L，这主要是由于夜间TSH激增幅度的逐渐增加。此外，显着的种族差异，TSH昼夜节律周期之间发生非洲裔美国人，太平洋岛屿，高加索population.Conclusions：TSH的参考区间显着不同的年龄，性别，一天中的小时，种族。一年中的时间不影响TSH参考区间，年龄、性别、一天中的小时和一年中的时间不影响游离T4参考区间。
Background: Establishing the reference interval for thyrotropin (TSH) and free thyroxine (T4) is clinically important because a number of disease states have been linked to alterations in TSH and free T4 concentrations that are within the 95% confidence interval for normal thyroid hormone values. Age, sex, time of day, and ethnicity are known to affect circulating levels of TSH and free T4 but have not been used to establish reference intervals. The purpose of this study was to define the reference interval for TSH and free T4 taking into account age, sex, ethnicity, and circadian and circannual variability.Methods: We performed a retrospective analysis of 465,593 TSH and 112,994 free T4 measurements from subjects ages 1-104 years with no thyroid disease using a single TSH and free T4 immunoassay method. Boundaries for the central 95% of patient values, taking into account hour of day, day of year, sex, and age were calculated.Results: Females had significantly higher TSH and free T4 levels than males; the magnitude of these differences did not exceed 0.1 mIU/L or 0.1 ng/dL respectively. Although the 2.5% TSH reference interval remains constant through the day, date, and age ranges, the upper limit (97.5%) of the TSH reference interval increases from 6.45 to 7.55 mIU/L with age, due primarily to a progressive increase in the amplitude of the nocturnal TSH surge. Additionally, significant ethnic differences in TSH circadian periodicity occur between African American, Pacific Island, and Caucasian populations.Conclusions: The reference interval for TSH varies significantly by age, sex, hour of day, and ethnicity. Time of year does not affect the TSH reference interval, and age, sex, hour of day and time of year do not affect the free T4 reference interval.