Establishment of trimester-specific thyroid stimulating hormone and free thyroxine reference interval in pregnant Chinese women using the Beckman Coulter UniCel™ DxI 600

AbstractThyroid-stimulating hormone (TSH) and free thyroxine (FT4) reference intervals are essential for screening and diagnosing thyroid dysfunction during pregnancy. The aim of this study was to establish method- and trimester-specific TSH and FT4 reference intervals in pregnant Chinese women using the Beckman Coulter UniCel™ DxI 600.A cross-sectional dataset analysis was performed. A total of 3507 participants were recruited, and 2743 were eligible for analysis to set reference intervals. TSH, FT4, and thyroid peroxidase antibody (TPOAb) levels were analyzed with the Beckman Coulter UniCel™ DxI 600 AccessThe calculated reference intervals for the first, second, and third trimesters were TSH: 0.06–3.13, 0.07–4.13 and 0.15–5.02 mIU/L, respectively, and FT4: 8.72–15.22, 7.10–13.55 and 6.16–12.03 pmol/L, respectively.Our reference intervals for TSH and FT4 are distinct from the ranges reported in the DxI 600 instruction manual and previously reported data, confirming the importance of method-specific reference intervals.

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Composite Reference Interval for Thyroid-Stimulating Hormone and Free Thyroxine, Comparison with Common Cutoff Values, and Reconsideration of Subclinical Thyroid Disease

Clinical Chemistry ◽

10.1373/clinchem.2009.124560 ◽

2009 ◽

Vol 55 (11) ◽

pp. 2019-2025 ◽

Cited By ~ 8

Author(s):

H Alec Ross ◽

Martin den Heijer ◽

Ad R M M Hermus ◽

Fred C G J Sweep

Keyword(s):

Probability Distribution ◽

Thyroid Disease ◽

Reference Interval ◽

Reference Intervals ◽

Thyroid Stimulating Hormone ◽

Free Thyroxine ◽

Thyroid Peroxidase ◽

Healthy Individuals ◽

Cutoff Values ◽

Stimulating Hormone

Abstract Background: Examination of the 2-dimensional probability distribution of thyroid-stimulating hormone (TSH) and free thyroxine (FT4) shows that the widths of the TSH and FT4 reference intervals derived from this bivariate distribution are mutually interdependent, an aspect commonly ignored when interpreting thyroid testing results with separate reference intervals for TSH and FT4. We desired to establish and critically evaluate a composite reference interval for TSH and FT4 to allow bivariate classification of biochemical thyroid conditions. Methods: FT4 and TSH results of 871 healthy individuals [361 women and 510 men, 18–40 years old, without history of thyroid-related disease or medication, negative for anti–thyroid peroxidase (anti-TPO) antibody] were transformed to standard normal variables by logarithmic transformation with correction for skewness and subsequent normalization. We established a 95% reference interval of the distance of each FT4/TSH pair of values to the center of the 2-dimensional probability distribution. Results: The bivariate 95% reference interval is enclosed by a circular profile with radius 2.45 SD. By contrast, conventional reference intervals comprise a square with the boundaries of −1.96 and +1.96 SD for both FT4 and TSH that enclose only 90% of all data. Compared with the ±1.96 SD square, the bivariate reference interval classified 4% fewer of 3651 healthy individuals older than 40 years as subclinically hyperthyroid and 14% fewer of 712 anti-TPO–positive healthy individuals as subclinically hypothyroid. Conclusions: Conventional application of separate cutoff values for FT4 and TSH leads to overestimation of the incidence of subclinical thyroid disease. Application of a composite overall reference interval is recommended.

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Trimester- and Assay-Specific Thyroid Reference Intervals for Pregnant Women in China

International Journal of Endocrinology ◽

10.1155/2016/3754213 ◽

2016 ◽

Vol 2016 ◽

pp. 1-5 ◽

Cited By ~ 7

Author(s):

Jinfang Xing ◽

Enwu Yuan ◽

Jing Li ◽

Yuchao Zhang ◽

Xiangying Meng ◽

...

Keyword(s):

Thyroid Function ◽

Chinese Women ◽

Reference Interval ◽

First Trimester ◽

Cross Sectional Study ◽

Reference Intervals ◽

Thyroid Stimulating Hormone ◽

Thyroid Peroxidase ◽

American Thyroid Association ◽

Cross Sectional

Objective. The guidelines of the American Thyroid Association (ATA) recommend an upper limit reference interval (RI) of thyroid stimulating hormone (TSH) of 2.5 mIU/L in the first trimester of pregnancy and 3.0 mIU/L in subsequent trimesters, but some reported ranges in China are significantly higher. Our study aimed to establish trimester- and assay-specific RIs for thyroid hormones in normal pregnant Chinese women. Methods. In this cross-sectional study, 2540 women with normal pregnancies (first trimester, n=398; second trimester, n=797; third trimester, n=1345) and 237 healthy nonpregnant control subjects were recruited. Serum TSH, free thyroxin (FT4), thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) levels were determined by automated chemiluminescence with an Immulite 2000 system (Siemens, Erlangen, Germany). After outliers were excluded, the 2.5–97.5th percentiles were used to define the RIs. Results. The RIs of thyroid function in the first, second, and third trimesters of pregnancy and in nonpregnant controls were 0.07–3.96, 0.27–4.53, 0.48–5.40, and 0.69–5.78 mIU/L for TSH and 9.16–18.12, 8.67–16.21, 7.80–13.90, and 8.24–16.61 pmol/L for FT4, respectively. Conclusion. The trimester- and assay-specific RIs of thyroid function during pregnancy differed between trimesters, which suggests that it is advisable to detect and avoid misclassification of thyroid dysfunction during pregnancy for women in Henan, China.

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Reference intervals of trimester-specific thyroid stimulating hormone and free thyroxine in Chinese women established by experimental and statistical methods

Journal of Clinical Laboratory Analysis ◽

10.1002/jcla.22344 ◽

2017 ◽

Vol 32 (4) ◽

pp. e22344 ◽

Cited By ~ 6

Author(s):

Lican Han ◽

Wei Zheng ◽

Yanhong Zhai ◽

Xin Xie ◽

Jingnan Zhang ◽

...

Keyword(s):

Statistical Methods ◽

Chinese Women ◽

Reference Intervals ◽

Thyroid Stimulating Hormone ◽

Free Thyroxine ◽

Stimulating Hormone

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The effect of thyroid antibody positivity on reference intervals for thyroid stimulating hormone (TSH) and free thyroxine (FT4) in an aged population

Clinical Chemistry and Laboratory Medicine (CCLM) ◽

10.1515/cclm.2005.236 ◽

2005 ◽

Vol 43 (12) ◽

Cited By ~ 17

Author(s):

Seija Eskelinen ◽

Pauli Suominen ◽

Tero Vahlberg ◽

Minna Löppönen ◽

Raimo Isoaho ◽

...

Keyword(s):

Reference Intervals ◽

Thyroid Stimulating Hormone ◽

Free Thyroxine ◽

Thyroid Peroxidase ◽

Thyroid Antibodies ◽

Thyroglobulin Antibodies ◽

Thyroid Antibody ◽

Aged Population ◽

Antibody Positivity ◽

Stimulating Hormone

AbstractOur aims were: 1) to analyze the effect of the methodology used to derive clinically feasible cut-off values for thyroid peroxidase antibodies (TPOAb) and thyroglobulin antibodies (TgAb), which exhibit highly skewed distributions; and 2) to describe the influence of thyroid antibodies on thyroid stimulating hormone (TSH) and free thyroxine (FT

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Establishment of Early Pregnancy Related Thyroid Hormone Models and Reference Intervals for Pregnant Women in China Based on Real World Data

Hormone and Metabolic Research ◽

10.1055/a-1402-0290 ◽

2021 ◽

Vol 53 (04) ◽

pp. 272-279

Author(s):

Chaochao Ma ◽

Xiaoqi Li ◽

Lixin Liu ◽

Xinqi Cheng ◽

Fang Xue ◽

...

Keyword(s):

Thyroid Hormone ◽

Thyroid Hormones ◽

Pregnant Women ◽

Early Pregnancy ◽

Gestational Age ◽

Dynamic Change ◽

Reference Intervals ◽

Thyroid Stimulating Hormone ◽

Free Thyroxine ◽

Stimulating Hormone

AbstractThyroid hormone reference intervals are crucial for diagnosing and monitoring thyroid dysfunction during early pregnancy, and the dynamic change trend of thyroid hormones during pregnancy can assist clinicians to assess the thyroid function of pregnant women. This study aims to establish early pregnancy related thyroid hormones models and reference intervals for pregnant women. We established two derived databases: derived database* and derived database#. Reference individuals in database* were used to establish gestational age-specific reference intervals for thyroid hormones and early pregnancy related thyroid hormones models for pregnant women. Individuals in database# were apparently healthy non-pregnant women. The thyroid hormones levels of individuals in database# were compared with that of individuals in database* using nonparametric methods and the comparative confidence interval method. The differences in thyroid stimulating hormone and free thyroxine between early pregnant and non-pregnant women were statistically significant (p<0.0001). The reference intervals of thyroid stimulating hormone, free thyroxine and free triiodothyronine for early pregnant women were 0.052–3.393 μIU/ml, 1.01–1.54 ng/dl, and 2.51–3.66 pg/ml, respectively. Results concerning thyroid stimulating hormone and free thyroxine reference intervals of early pregnancy are comparable with those from other studies using the same detection platform. Early pregnancy related thyroid hormones models showed various change patterns with gestational age for thyroid hormones. Early pregnancy related thyroid hormones models and reference intervals for pregnant women were established, so as to provide accurate and reliable reference basis for the diagnosing and monitoring of maternal thyroid disfunction in early pregnancy.

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Evaluation of Thyroid Function in Pregnant Women Using Automated Immunoassays

Clinical Chemistry ◽

10.1093/clinchem/hvab009 ◽

2021 ◽

Author(s):

K Aaron Geno ◽

Matthew S Reed ◽

Mark A Cervinski ◽

Robert D Nerenz

Keyword(s):

Pregnant Women ◽

Equilibrium Dialysis ◽

Reference Interval ◽

First Trimester ◽

Reference Intervals ◽

Free Thyroxine ◽

Specific Reference ◽

Childbearing Age ◽

Thyroid Autoantibody ◽

The Impact

Abstract Introduction Automated free thyroxine (FT4) immunoassays are widely available, but professional guidelines discourage their use in pregnant women due to theoretical under-recoveries attributed to increased thyroid hormone binding capacity and instead advocate the use of total T4 (TT4) or free thyroxine index (FTI). The impact of this recommendation on the classification of thyroid status in apparently euthyroid pregnant patients was evaluated. Methods After excluding specimens with thyroid autoantibody concentrations above reference limits, thyroid-stimulating hormone (TSH), FT4, TT4, and T-uptake were measured on the Roche Cobas® platform in remnant clinical specimens from at least 147 nonpregnant women of childbearing age and pregnant women at each trimester. Split-sample comparisons of FT4 as measured by the Cobas and equilibrium dialysis were performed. Results FT4 decreased with advancing gestational age by both immunoassay and equilibrium dialysis. TSH declined during the first trimester, remained constant in the second, and increased throughout the third, peaking just before delivery. Interpretation of TT4 concentrations using 1.5-times the nonpregnant reference interval classified 13.6% of first trimester specimens below the lower reference limit despite TSH concentrations within trimester-specific reference intervals. Five FTI results from 480 pregnant individuals (about 1.0%) fell outside the manufacturer’s reference interval. Conclusions Indirect FT4 immunoassay results interpreted in the context of trimester-specific reference intervals provide a practical and viable alternative to TT4 or FTI. Declining FT4 and increasing TSH concentrations near term suggest that declining FT4 is not an analytical artifact but represents a true physiological change in preparation for labor and delivery.

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Method specific second-trimester reference intervals for thyroid-stimulating hormone and free thyroxine

Clinical Biochemistry ◽

10.1016/j.clinbiochem.2008.12.004 ◽

2009 ◽

Vol 42 (7-8) ◽

pp. 750-753 ◽

Cited By ~ 16

Author(s):

Rechelle Silvio ◽

Karly J. Swapp ◽

Sonia L. La'ulu ◽

Kara Hansen-Suchy ◽

William L. Roberts

Keyword(s):

Reference Intervals ◽

Thyroid Stimulating Hormone ◽

Free Thyroxine ◽

Second Trimester ◽

Stimulating Hormone

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Preterm to term infant postmenstrual age reference intervals for thyroid-stimulating hormone and free thyroxine

Pediatric Research ◽

10.1038/s41390-021-01838-3 ◽

2021 ◽

Author(s):

George M. Ziegler ◽

Jonathan L. Slaughter ◽

Monika Chaudhari ◽

Herveen Singh ◽

Pablo J. Sánchez ◽

...

Keyword(s):

Reference Intervals ◽

Thyroid Stimulating Hormone ◽

Term Infant ◽

Free Thyroxine ◽

Postmenstrual Age ◽

Stimulating Hormone

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Reference Intervals of Thyroid Hormones and Correlation of BMI with Thyroid Function in Healthy Zhuang Ethnic Pregnant Women

BioMed Research International ◽

10.1155/2018/2032413 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Yonghong Sheng ◽

Dongping Huang ◽

Shun Liu ◽

Xuefeng Guo ◽

Jiehua Chen ◽

...

Keyword(s):

Thyroid Hormones ◽

Pregnant Women ◽

Thyroid Function ◽

Reference Intervals ◽

Thyroid Stimulating Hormone ◽

Specific Reference ◽

American Thyroid Association ◽

Reference Ranges ◽

Free Triiodothyronine ◽

Cross Sectional

Ethnic differences in the level of thyroid hormones exist among individuals. The American Thyroid Association (ATA) recommends that an institution or region should establish a specific thyroid hormone reference value for each stage of pregnancy. To date, a limited number of studies have reported the level of thyroid hormones in Chinese minorities, and the exact relationship between BMI and thyroid function in pregnant women is ill. This study was performed to establish trimester-specific reference ranges of thyroid hormones in Zhuang ethnic pregnant women and explore the role of body mass index (BMI) on thyroid function. A total of 3324 Zhuang ethnic health pregnant women were recruited in this Zhuang population-based retrospective cross-sectional study. The values of thyroid stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were determined by automatic chemiluminescence immunoassay analyzer. Multivariate linear regression and binary logistic regression were constructed to evaluate the influence of BMI on the thyroid function. The established reference intervals for the serum thyroid hormones in three trimesters were as follows: TSH, 0.02–3.28, 0.03–3.22, and 0.08-3.71 mIU/L; FT4, 10.57–19.76, 10.05–19.23, and 8.96–17.75 pmol/L; FT3, 3.51–5.64, 3.42–5.42, and 2.93–5.03 pmol/L. These values were markedly lower than those provided by the manufacturers for nonpregnant adults which can potentially result in 6.10% to 19.73% misclassification in Zhuang pregnant women. Moreover, BMI was positively correlated with isolated hypothyroxinemia (OR=1.081, 95% CI=1.007–1.161), while the correlation between the BMI and subclinical hypothyroidism was not statistically significant (OR=0.991, 95% CI=0.917–1.072). This is the first study focusing on the reference ranges of thyroid hormones in Guangxi Zhuang ethnic pregnant women, which will improve the care of them in the diagnosis and treatment. We also found that high BMI was positively associated with the risk of isolated hypothyroxinemia.

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