Reference Ranges and Determinants of Thyroid Function and TSH Receptor Antibodies During Early Pregnancy in Nepal

IF 3 3区医学 Q2 ENDOCRINOLOGY & METABOLISM

Clinical Endocrinology Pub Date : 2024-12-16 DOI:10.1111/cen.15175

Kjersti S. Bakken, Apeksha Niraula, Ram K. Chandyo, Manjeswori Ulak, Laxman Shrestha, Vijay Kumar Sharma, Tor A. Strand, Tim I. M. Korevaar

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引用次数: 0

Abstract

Objective

Different definitions of thyroid dysfunction during pregnancy may lead to under or overtreatment. The aims of this study were to (1) define population-based pregnancy-specific reference ranges for thyroid dysfunction during early pregnancy in Nepal and assess the impact of antibody positivity, (2) quantify the diagnostic impact of population-based reference ranges compared with current practice and (3) assess the determinants of thyroid function and antibody positivity.

Methods

A total of 800 healthy pregnant women aged 20–40 years in the Bhaktapur municipality were included. Population-based reference ranges for thyroid hormones levels were defined as 2.5th and 97.5th percentiles using competitive immunoluminometric assay design. Thyroid disease cases and those with recommended treatment indications were calculated using current non-pregnancy new reference ranges. Multivariate regression analyses were performed to identify the determinants of thyroid hormones and antibody levels.

Results

Median gestational age was 11 weeks. The reference interval was 0.05–3.69 µLU/mL for thyroid stimulating hormone (TSH) and 8.89–15.28 pg/mL for free tetraiodothyronine (fT4) after excluding thyroid peroxidase antibody-positive women. Compared with the current non-pregnancy reference ranges, the new calculations increased the number of women who required treatment from 5 to 12 (0.9% increase). We identified 19 women (2.4%) who were positive for TSH receptor antibody (TRAb). We could not identify the determinants of TRAb positivity, and TRAb positivity was not associated with TSH or fT4 levels.

Conclusions

We found meaningful changes using population-based pregnancy-specific TSH and fT4 reference intervals and encourage further studies in other low- and middle-income settings. Our findings suggest that population screening for TRAb is not clinically meaningful.

Trial Registration

Clinical Trial Registration: U1111-1183-4093.

Abstract Image

查看原文本刊更多论文

尼泊尔妊娠早期甲状腺功能和TSH受体抗体的参考范围和决定因素。

目的：对孕期甲状腺功能异常的不同定义可能会导致治疗不足或过度治疗。本研究的目的是：（1）定义尼泊尔妊娠早期甲状腺功能异常的人群特异性参考范围，并评估抗体阳性的影响；（2）量化人群特异性参考范围对诊断的影响，并与目前的做法进行比较；（3）评估甲状腺功能和抗体阳性的决定因素：方法：共纳入了巴克塔普尔市 800 名 20-40 岁的健康孕妇。采用竞争性免疫光度测定设计，将甲状腺激素水平的人群参考范围定义为 2.5 和 97.5 百分位数。甲状腺疾病病例和具有建议治疗指征的病例采用当前非孕期新参考范围进行计算。进行多变量回归分析以确定甲状腺激素和抗体水平的决定因素：结果：中位孕龄为 11 周。排除甲状腺过氧化物酶抗体阳性妇女后，促甲状腺激素（TSH）的参考区间为 0.05-3.69 µLU/mL，游离四碘甲状腺原氨酸（fT4）的参考区间为 8.89-15.28 pg/mL。与当前的非孕期参考范围相比，新的计算方法使需要治疗的女性人数从 5 人增加到 12 人（增加了 0.9%）。我们发现有 19 名妇女（2.4%）的促甲状腺激素受体抗体（TRAb）呈阳性。我们无法确定 TRAb 阳性的决定因素，TRAb 阳性与 TSH 或 fT4 水平无关：我们发现，使用基于人群的妊娠特异性促甲状腺激素和 fT4 参考区间会产生有意义的变化，因此鼓励在其他中低收入环境中开展进一步研究。我们的研究结果表明，人群TRAb筛查没有临床意义：临床试验注册：U1111-1183-4093.

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来源期刊

Clinical Endocrinology 医学-内分泌学与代谢

CiteScore

6.40

自引率

3.10%

发文量

192

审稿时长

1 months

期刊介绍： Clinical Endocrinology publishes papers and reviews which focus on the clinical aspects of endocrinology, including the clinical application of molecular endocrinology. It does not publish papers relating directly to diabetes care and clinical management. It features reviews, original papers, commentaries, correspondence and Clinical Questions. Clinical Endocrinology is essential reading not only for those engaged in endocrinological research but also for those involved primarily in clinical practice.