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Li S, Guo W, Meng Q, Zhu M, Wei H, Ji F, Tan L, Zhang W. The association between thyroid-stimulating hormone and thyroid nodules, goiter and thyroid antibody positivity. Front Endocrinol (Lausanne) 2023; 14:1204552. [PMID: 37850098 PMCID: PMC10577406 DOI: 10.3389/fendo.2023.1204552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Accepted: 09/14/2023] [Indexed: 10/19/2023] Open
Abstract
Background The relationship between normal thyroid-stimulating hormone (TSH) levels and thyroid disease in adults remains controversial. This study aimed to investigate the correlation between serum TSH levels, particularly those falling within the normal range, and thyroid diseases in Chinese adults, including thyroid nodules (TN), goiter (GR), and thyroid antibody positivity. Materials and methods This research was a cross-sectional study conducted in an adult population in Tianjin, China. Thyroid volume (Tvol) and TN were assessed using thyroid ultrasonography. Fasting venous blood and spot urine samples were collected to evaluate thyroid function and iodine status. Results A total of 2460 subjects participated in the survey. The prevalence of thyroid dysfunction was 9.76%, and abnormal TSH levels were found to potentially increase the risk of GR and thyroid antibody positivity in adults. A total of 2220 subjects with TSH within the normal reference range were included in the further study. In these patients, Tvol decreased as TSH levels increased, in both men and women (P < 0.0001). Low TSH levels (0.27-1.41 IU/mL) were identified as a risk factor for TN (odds ratio [OR], 1.46; 95% CI: 1.14-1.87) and GR (OR 5.90, 95% CI 2.27-15.3). Upon stratification by sex and age, the risk of TN was found to be higher in women and elderly individuals (≥60 years old), while the risk of GR was found to be higher in men and younger individuals (<60 years old). High TSH levels (2.55-4.2 IU/mL) were identified as a risk factor for thyroid antibody positivity (OR, 1.53; 95% CI: 1.11-2.10). Men and younger individuals with high TSH levels exhibited a higher risk of thyroid antibody positivity. Conclusion In adults with normal TSH levels, low TSH levels were associated with an increased risk of TN and GR, whereas high TSH levels were associated with thyroid antibody positivity. The research also suggests that adults whose TSH levels at upper or lower limits of the normal range should be reviewed regularly.
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Affiliation(s)
- Shaohan Li
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Wenxing Guo
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Qi Meng
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Mei Zhu
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Hongyan Wei
- Department of Endocrinology and Metabolism, Tianjin Medical University General Hospital, Tianjin, China
| | - Fengying Ji
- Qingdao Municipal Center for Disease Control and Prevention, Qingdao, China
- Qingdao Institute of Preventive Medicine, Qingdao, China
| | - Long Tan
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
| | - Wanqi Zhang
- Department of Nutrition and Food Hygiene, School of Public Health, Tianjin Medical University, Tianjin, China
- Tianjin Key Laboratory of Environment, Nutrition and Public Health, Tianjin, China
- Tianjin Key Laboratory of Hormones and Development (Ministry of Health), Tianjin, China
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Perros P, Van Der Feltz-Cornelis C, Papini E, Nagy EV, Weetman AP, Hegedüs L. The enigma of persistent symptoms in hypothyroid patients treated with levothyroxine: A narrative review. Clin Endocrinol (Oxf) 2023; 98:461-468. [PMID: 33783849 DOI: 10.1111/cen.14473] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2021] [Revised: 03/24/2021] [Accepted: 03/25/2021] [Indexed: 12/19/2022]
Abstract
A significant minority of patients with hypothyroidism report persistent symptoms despite achieving normal thyroid biochemistry after levothyroxine (L-T4) replacement. Four principal lines of thinking, which are not mutually exclusive, may explain this enigma. The 'low tissue liothyronine hypothesis' emphasizes the potential imperfections of L-T4 replacement therapy that may lead to hypothyroidism in some tissues such as the brain, while others (eg hypothalamus) are euthyroid. The 'Somatic Symptom and Related Disorders hypothesis' draws attention to an incidental coexistence of a diagnosis of Somatic Symptom and Related Disorders in patients with treated hypothyroidism. The 'autoimmune neuroinflammation hypothesis' highlights the potential consequences of inflammatory mediators due to thyroid autoimmunity (the commonest cause of hypothyroidism) on the brain. The 'comorbidities and psychosocial hypothesis' implicates a variety of physical and psychosocial factors that have been noted to be associated with a diagnosis of hypothyroidism, which may be primarily the cause of persistent complaints. Over the past twenty years, a great deal of time and effort has been expended pursuing the 'low tissue liothyronine hypothesis', which has failed to yield results that translate to patient benefits. This has skewed the balance in clinical practice, in favour of pursuing answers relating to L-T4 and liothyronine combination treatment, while the alternative explanations have been downplayed and potentially useful interventions have been given insufficient attention.
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Affiliation(s)
- Petros Perros
- Department of Endocrinology, Royal Victoria Infirmary, Newcastle upon Tyne, UK
| | | | - Enrico Papini
- Department of Endocrinology and Metabolism, Regina Apostolorum Hospital, Albano, Rome, Italy
| | - Endre V Nagy
- Division of Endocrinology, Department of Medicine, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Anthony P Weetman
- Department of Oncology and Metabolism, University of Sheffield, Sheffield, UK
| | - Laszlo Hegedüs
- Department of Endocrinology, Odense University Hospital, Odense, Denmark
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3
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Smajdor J, Paczosa-Bator B, Piech R. Advances on Hormones and Steroids Determination: A Review of Voltammetric Methods since 2000. MEMBRANES 2022; 12:1225. [PMID: 36557132 PMCID: PMC9782681 DOI: 10.3390/membranes12121225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/18/2022] [Accepted: 11/22/2022] [Indexed: 06/17/2023]
Abstract
This article presents advances in the electrochemical determination of hormones and steroids since 2000. A wide spectrum of techniques and working electrodes have been involved in the reported measurements in order to obtain the lowest possible limits of detection. The voltammetric and polarographic techniques, due to their sensitivity and easiness, could be used as alternatives to other, more complicated, analytical assays. Still, growing interest in designing a new construction of the working electrodes enables us to prepare new measurement procedures and obtain lower limits of detection. A brief description of the measured compounds has been presented, along with a comparison of the obtained results.
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Mele C, Mai S, Cena T, Pagano L, Scacchi M, Biondi B, Aimaretti G, Marzullo P. The pattern of TSH and fT4 levels across different BMI ranges in a large cohort of euthyroid patients with obesity. Front Endocrinol (Lausanne) 2022; 13:1029376. [PMID: 36313780 PMCID: PMC9606412 DOI: 10.3389/fendo.2022.1029376] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 09/26/2022] [Indexed: 11/13/2022] Open
Abstract
PURPOSE A multifold association relates the hypothalamo-pituitary-thyroid axis to body weight. The potential underlying mechanisms are incompletely understood. Further, the mild severity of obesity and the small proportion of individuals with obesity in so far published cohort studies provide little insights on metabolic correlates of thyroid function in obesity. METHODS We retrospectively enrolled 5009 adults with obesity (F/M, 3448/1561; age range, 18-87 years; BMI range, 30.0-82.7 kg/m2), without known thyroid disease in a study on TSH and fT4 levels, lipid profile, glucose homeostasis and insulin resistance, anthropometric parameters including BIA-derived fat mass (%FM) and fat-free mass (FFM). RESULTS The overall reference interval for TSH in our obese cohort was 0.58-5.07 mIU/L. As subgroups, females and non-smokers showed higher TSH levels as compared to their counterparts (p<0.0001 for both), while fT4 values were comparable between groups. There was a significant upward trend for TSH levels across incremental BMI classes in females, while the opposite trend was seen for fT4 levels in males (p<0.0001 for both). Expectedly, TSH was associated with %FM and FFM (p<0,0001 for both). TSH and fT4 showed correlations with several metabolic variables, and both declined with aging (TSH, p<0.0001; fT4, p<0.01). In a subgroup undergoing leptin measurement, leptin levels were positively associated with TSH levels (p<0.01). At the multivariable regression analysis, in the group as a whole, smoking habit emerged as the main independent predictor of TSH (β=-0.24, p<0.0001) and fT4 (β=-0.25, p<0.0001) levels. In non-smokers, %FM (β=0.08, p<0.0001) and age (β=-0.05, p<0.001) were the main significant predictors of TSH levels. In the subset of nonsmokers having leptin measured, leptin emerged as the strongest predictor of TSH levels (β=0.17, p<0.01). CONCLUSIONS Our study provides evidence of a gender- and smoking-dependent regulation of TSH levels in obesity.
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Affiliation(s)
- Chiara Mele
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
- *Correspondence: Chiara Mele,
| | - Stefania Mai
- Istituto Auxologico Italiano, IRCCS, Laboratory of Metabolic Research, S. Giuseppe Hospital, Piancavallo, Italy
| | - Tiziana Cena
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
| | - Loredana Pagano
- Division of Endocrinology, Diabetology and Metabolism, Department of Medical Sciences, University of Turin, Turin, Italy
| | - Massimo Scacchi
- Istituto Auxologico Italiano, IRCCS, Division of General Medicine, S. Giuseppe Hospital, Piancavallo, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Bernadette Biondi
- Department of Clinical Medicine and Surgery, University of Naples Federico II, Naples, Italy
| | - Gianluca Aimaretti
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
| | - Paolo Marzullo
- Department of Translational Medicine, University of Piemonte Orientale, Novara, Italy
- Istituto Auxologico Italiano, IRCCS, Laboratory of Metabolic Research, S. Giuseppe Hospital, Piancavallo, Italy
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Abstract
Abstract
The indirect approach to defining reference intervals operates ‘a posteriori’, on stored laboratory data. It relies on being able to separate healthy and diseased populations using one or both of clinical techniques or statistical techniques. These techniques are also fundamental in a priori, direct reference interval approaches. The clinical techniques rely on using clinical data that is stored either in the electronic health record or within the laboratory database, to exclude patients with possible disease. It depends on the investigators understanding of the data and the pathological impacts on tests. The statistical technique relies on identifying a dominant, apparently healthy, typically Gaussian distribution, which is unaffected by the overlapping populations with higher (or lower) results. It depends on having large databases to give confidence in the extrapolation of the narrow portion of overall distribution representing unaffected individuals. The statistical issues involved can be complex, and can result in unintended bias, particularly when the impacts of disease and the physiological variations in the data are under appreciated.
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Affiliation(s)
- Kenneth A. Sikaris
- Department of Biochemistry , Melbourne Pathology , Collingwood , VIC , Australia
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6
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Wang X, Li Y, Zhai X, Wang H, Zhang F, Gao X, Liu S, Teng W, Shan Z. Reference Intervals for Serum Thyroid-Stimulating Hormone Based on a Recent Nationwide Cross-Sectional Study and Meta-Analysis. Front Endocrinol (Lausanne) 2021; 12:660277. [PMID: 34140930 PMCID: PMC8204855 DOI: 10.3389/fendo.2021.660277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 03/29/2021] [Indexed: 01/11/2023] Open
Abstract
OBJECTIVE The aim of our study was to compare the reference intervals (RIs) [median (2.5th-97.5th percentiles)] for thyroid-stimulating hormone (TSH) between subgroups stratified by ethnicity and iodine status in a global context. DESIGN AND METHODS Primary data were derived from a recently published cross-sectional study in mainland China. Secondary data were obtained from online databases. The RIs for TSH were calculated in the reference population according to the National Academy of Clinical Biochemistry (NACB) standard and in the disease-free population. A meta-analysis of ethnicity- and iodine status-specific TSH RIs was performed. RESULTS The primary data showed that the TSH RI (mU/L) in the disease-free population was 2.33 (0.67, 7.87), which is wider than the published RI [2.28 (0.74, 7.04)] in the reference population. The meta-analysis showed that whether in the reference or disease-free population, the RIs in Yellows were much higher than those in Caucasians. In the reference population, the median and 2.5th percentile in the iodine-sufficient subgroup were both lower than the iodine-deficient or more-than-adequate subgroup, while the 97.5th percentile showed a positive trend with increasing sufficiency of iodine. However, in the disease-free population, the iodine-sufficient subgroup had a lower median and 97.5th percentile but higher 2.5th percentile than the iodine-deficient subgroup. CONCLUSION Yellows have a higher TSH RI than Caucasians. In the reference population, both the median and 2.5th percentile TSH in the iodine-sufficient population were the lowest among the different iodine status subgroups, while the 97.5th percentile of TSH showed an upward trend with increasing iodine sufficiency.
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Affiliation(s)
- Xichang Wang
- Department of Endocrinology and Metabolism and the institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang, China
| | - Yongze Li
- Department of Endocrinology and Metabolism and the institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang, China
| | - Xiaodan Zhai
- Department of Endocrinology and Metabolism, Shengjing Affiliated Hospital of China Medical University, Shenyang, China
| | - Haoyu Wang
- Department of Endocrinology and Metabolism and the institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang, China
| | - Fan Zhang
- Department of Endocrinology and Metabolism and the institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang, China
| | - Xiaotong Gao
- Department of Endocrinology and Metabolism and the institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang, China
| | - Shengyu Liu
- Department of Endocrinology and Metabolism and the institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang, China
| | - Weiping Teng
- Department of Endocrinology and Metabolism and the institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang, China
| | - Zhongyan Shan
- Department of Endocrinology and Metabolism and the institute of Endocrinology, The NHC Key Laboratory of Diagnosis and Treatment of Thyroid Diseases, The First Hospital of China Medical University, Shenyang, China
- *Correspondence: Zhongyan Shan,
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7
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Abdulateef DS, Mahwi TO. Assessment of subclinical hypothyroidism for a clinical score and thyroid peroxidase antibody: a comparison with euthyroidism grouped by different thyroid-stimulating hormone levels. ASIAN BIOMED 2019. [DOI: 10.1515/abm-2019-0045] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Background
Subclinical hypothyroidism (SCH) might have many symptoms of hypothyroidism. The controversy appears to lower the level of thyroid-stimulating hormone (TSH) and group subjects with TSH of more than 3 or even 2.5 mIU/L as SCH subjects.
Objectives
To assess SCH subjects both clinically using Zulewski clinical score and biochemically and to evaluate whether the euthyroid subjects with high-normal TSH (HNT) have any clinical symptom or subnormal biochemical finding.
Methods
A prospective cross-sectional study of 233 subjects, 67 with SCH and 166 euthyroidism, was conducted. Euthyroid subjects were divided according to the level of TSH as HNT (>2.5 mIU/L) and low-normal TSH (0.5–2.5 mIU/L). The subjects were examined for clinical feature including Zulewski clinical score and biochemical evaluations including thyroid peroxidase antibody (TPO-Ab) titer. The comparisons between groups were assessed using independent sample t test, and correlations between variables were evaluated using Pearson correlation.
Results
A significantly higher clinical score and higher frequencies of symptoms were found in the SCH group compared to the euthyroid group. The most frequent symptom was fatigue. Euthyroid subjects with HNT were found to have higher TPO-Ab titers than those with low-normal TSH, P < 0.05. The Zulewski clinical score was positively correlated with TSH and TPO-Ab titer but negatively correlated with the FT4 level, P < 0.05.
Conclusions
Zulewski clinical score is higher in SCH subjects compared to euthyroid subjects and can aid in assessing SCH subjects. A significant correlation exists between Zulewski clinical score and each of the TSH, FT4, and TPO-Ab titer levels. The frequency of TPO-Ab positivity is high in SCH. Additionally, euthyroid with higher TSH levels has higher level of TPO-Ab titer but not higher clinical score.
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Affiliation(s)
- Darya S. Abdulateef
- Department of Physiology, College of Medicine, University of Sulaimani , Sulaimani 46001 , Kurdistan , Iraq
| | - Taha O. Mahwi
- Department of Medicine, College of Medicine, University of Sulaimani , Sulaimani 46001 , Kurdistan , Iraq
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Leduc-Robert G, Iews M, Abdelkareem AO, Williams C, Bloomenthal D, Abdelhafez F, Bedaiwy MA. Prevalence of thyroid autoimmunity and effect of levothyroxine treatment in a cohort of 1064 patients with recurrent pregnancy loss. Reprod Biomed Online 2019; 40:582-592. [PMID: 32160949 DOI: 10.1016/j.rbmo.2019.11.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 10/31/2019] [Accepted: 11/26/2019] [Indexed: 01/08/2023]
Abstract
RESEARCH QUESTION Does initiating levothyroxine treatment based on thyroid-stimulating hormone (TSH) >2.5 mIU/l or thyroid autoimmunity improve pregnancy continuation rates in recurrent pregnancy loss (RPL) patients? DESIGN A retrospective cohort study of 1064 RPL patients, in which subjects were classified as either euthyroid (TSH 0.1 to ≤2.5 mIU/l), borderline-subclinical hypothyroid (borderline-SCH, TSH 2.5 to ≤4 mIU/l) or subclinical hypothyroid (SCH, TSH 4 to ≤10 mIU/l). For subjects with ≥2 pregnancy losses and a subsequent pregnancy with known outcome, a comparison was done of the pregnancy continuation rate past 10 weeks of treated and untreated borderline-SCH (n = 98) and untreated euthyroid (n = 279) subjects, and between subjects with positive (n = 18) and negative (n = 206) thyroid peroxidase (TPOAb tests) within the borderline-SCH and euthyroid groups. RESULTS 72.7% were euthyroid (721/992), 19.4% (192/992) were borderline-SCH, and 5.4% (54/992) were subclinically hypothyroid (SCH). Of 401 women with a subsequent pregnancy of known outcome at 10 gestational weeks, 21% received treatment with levothyroxine. 57.7% of subjects had a TPOAb test, which was positive in 9.25% (37/400) in euthyroid, 16.5% (22/133) in borderline-SCH subjects and 35.3% (12/34) in SCH subjects. Treatment did not improve pregnancy continuation rates in borderline-SCH subjects (P = 0.392). There was no difference in pregnancy outcomes based on TPOAb status and treatment for borderline-SCH subjects (P = 0.4214), or based on TPOAb status for euthyroid subjects (P = 0.2668). CONCLUSIONS Treatment of hypothyroidism in pregnancy should be initiated based on a TSH >4 mIU/l. Treatment initiation based on thyroid autoimmunity or a TSH >2.5 mIU/l may result in overtreatment.
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Affiliation(s)
- Geneviève Leduc-Robert
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics & Gynaecology, University of British Columbia, BC Women and Children's Hospital, Vancouver BC, Canada
| | - Mahmoud Iews
- Department of Obstetrics and Gynaecology, South Valley University, Qena, Egypt
| | - Amr O Abdelkareem
- Department of Obstetrics and Gynaecology, Sohag University, Sohag, Egypt
| | - Christina Williams
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics & Gynaecology, University of British Columbia, BC Women and Children's Hospital, Vancouver BC, Canada
| | - Dena Bloomenthal
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics & Gynaecology, University of British Columbia, BC Women and Children's Hospital, Vancouver BC, Canada
| | - Faten Abdelhafez
- Department of Obstetrics and Gynaecology, Assiut University, Assiut, Egypt
| | - Mohamed A Bedaiwy
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics & Gynaecology, University of British Columbia, BC Women and Children's Hospital, Vancouver BC, Canada.
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Rotondi M, Capelli V, Chiovato L, Nappi RE. 2017 ATA guidelines on the management of thyroid dysfunctions in pregnancy: what do OB/GYNs need to know? Gynecol Endocrinol 2019; 35:276-279. [PMID: 30721102 DOI: 10.1080/09513590.2018.1532496] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
In the past two decades, the issue of thyroid dysfunctions during pregnancy and the postpartum period received increasing attention by both endocrinologists and obstetrics/gynecologists (OB/GYNs), the latter often became the first to diagnose an impaired thyroid function in pregnant women. In this setting, a series of different clinical guidelines have been published and reviewed, the latest ones being represented by the 2017 ATA guidelines, which extensively address a wide variety of topics, including iodine supplementation, thyroid autoimmunity, hyper- and hypo-thyroidism, thyroid nodules and cancer, post-partum management, as well as the need for pre-conception screening. Aim of this editorial is to offer a practical guidance to the OB/GYN reader by focusing upon evidence-based changes introduced by the latest guidelines, with particular regard to: (a) prescribing further endocrine testing before referral; (b) providing evidence-based answers to some of the frequently asked questions.
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Affiliation(s)
- Mario Rotondi
- a Department of Endocrinology , IRCCS Maugeri Foundation, University of Pavia , Pavia , Italy
| | - Valentina Capelli
- a Department of Endocrinology , IRCCS Maugeri Foundation, University of Pavia , Pavia , Italy
| | - Luca Chiovato
- a Department of Endocrinology , IRCCS Maugeri Foundation, University of Pavia , Pavia , Italy
| | - Rossella E Nappi
- b Research Center for Reproductive Medicine, Gynecological Endocrinology and Menopause, IRCCS S. Matteo Hospital, University of Pavia , Italy
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Lillevang-Johansen M, Abrahamsen B, Jørgensen HL, Brix TH, Hegedüs L. Duration of Hyperthyroidism and Lack of Sufficient Treatment Are Associated with Increased Cardiovascular Risk. Thyroid 2019; 29:332-340. [PMID: 30648498 DOI: 10.1089/thy.2018.0320] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Cardiovascular disease remains the most prevalent cause of death in hyperthyroidism. However, the impact on cardiovascular events of varying thyroid status and of treatment remains unclarified. The aims of this study were to investigate the association between hyperthyroidism and cardiovascular events in treated and untreated hyperthyroid individuals, as well as exploring the impact of cumulative periods of hyperthyroidism as a proxy for undertreatment on cardiovascular events. METHOD This was a case-control study nested within a population-based cohort of individuals attending health services in Funen County, Denmark, in the period from 1995 to 2011. Data on comorbidities and mortality were collected from The Danish National Patient Register and The Danish Register of Causes of Death. Participants were 275,467 individuals with at least one serum thyrotropin (TSH) measurement in the study period. Hyperthyroidism was defined as at least two measurements of decreased serum TSH within six months, separated by at least 14 days. Incident cases of cardiovascular disease (myocardial infarction, atrial fibrillation, heart failure, stroke, and cardiovascular death) were matched with controls. Conditional logistic regression analyses were performed to calculate odds ratios (OR) for exposure to hyperthyroidism, adjusting for preexisting comorbidities. RESULTS A total of 20,651 individuals experienced a cardiovascular event (9.5% incidence rate 13.2/1000 person-years [confidence interval (CI) 13.0-13.4]) compared to euthyroid individuals, conditional logistic regression showed increased cardiovascular risk in untreated hyperthyroid patients (OR = 1.25 [CI 1.06-1.48], p = 0.007) but not in treated hyperthyroid patients (OR = 1.04 [CI 0.90-1.22], p = 0.57)]. The OR for cardiovascular events per six months of decreased TSH was 1.09 ([CI 1.05-1.14], p < 0.001) in treated hyperthyroid individuals, and 1.10 ([CI 1.05-1.15], p < 0.001) in untreated hyperthyroid individuals. CONCLUSIONS The risk of cardiovascular disease was found to be increased in untreated hyperthyroid patients, and the duration of decreased TSH associated with increasing risk of cardiovascular outcomes in both treated and untreated hyperthyroid individuals. This suggests that increased cardiovascular risk is driven not only by lack of treatment but also by insufficient therapy. The results support timely treatment and careful monitoring of hyperthyroid patients in order to reduce cardiovascular risk.
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Affiliation(s)
- Mads Lillevang-Johansen
- 1 Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark
- 2 Institute of Clinical Research and University of Southern Denmark, Odense, Denmark
| | - Bo Abrahamsen
- 2 Institute of Clinical Research and University of Southern Denmark, Odense, Denmark
- 3 Odense Patient data Explorative Network OPEN, University of Southern Denmark, Odense, Denmark
- 4 Department of Medicine, Holbæk Hospital, Holbæk, Denmark
| | - Henrik Løvendahl Jørgensen
- 5 Department of Clinical Biochemistry, Hvidovre Hospital, Copenhagen, Denmark
- 6 Department of Clinical Medicine, University of Copenhagen, Denmark
| | - Thomas Heiberg Brix
- 1 Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark
| | - Laszlo Hegedüs
- 1 Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark
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11
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Abstract
BACKGROUND Both overt hypothyroidism as well as minor elevations of serum thyrotropin (TSH) levels associated with thyroid hormones within their respective reference ranges (termed subclinical hypothyroidism) are relatively common in older individuals. There is growing evidence that treatment of subclinical hypothyroidism may not be beneficial, particularly in an older person. These findings are relevant at a time when treatment with thyroid hormones is increasing and more than 10-15% of people aged over 80 years are prescribed levothyroxine replacement therapy. MAIN BODY The prevalence of hypothyroidism increases with age. However, the reference range for TSH also rises with age, as the population distribution of TSH concentration progressively rises with age. Furthermore, there is evidence to suggest that minor TSH elevations are not associated with important outcomes such as impaired quality of life, symptoms, cognition, cardiovascular events and mortality in older individuals. There is also evidence that treatment of mild subclinical hypothyroidism may not benefit quality of life and/or symptoms in older people. It is unknown whether treatment targets should be reset depending on the age of the patient. It is likely that some older patients with non-specific symptoms and incidental mild subclinical hypothyroidism may be treated with thyroid hormones and could potentially be harmed as a result. This article reviews the current literature pertaining to hypothyroidism with a special emphasis on the older individual and assesses the risk/benefit impact of contemporary management on outcomes in this age group. CONCLUSIONS Current evidence suggests that threshold for treating mild subclinical hypothyroidism in older people should be high. It is reasonable to aim for a higher TSH target in treated older hypothyroid patients as their thyroid hormone requirements may be lower. In addition, age-appropriate TSH reference ranges should be considered in the diagnostic pathway of identifying individuals at risk of developing hypothyroidism. Appropriately designed and powered randomised controlled trials are required to confirm risk/benefit of treatment of subclinical hypothyroidism in older people. Until the results of such RCTs are available to guide clinical management international guidelines should be followed that advocate a conservative policy in the management of mild subclinical hypothyroidism in older individuals.
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Affiliation(s)
- Owain Leng
- Department of Endocrinology, Newcastle upon Tyne Hospitals NHS Foundation Trust, Newcastle upon Tyne, NE1 4LP UK
| | - Salman Razvi
- Department of Endocrinology, Gateshead Health NHS Foundation Trust, Queen Elizabeth Hospital, Gateshead, Gateshead, NE9 6SX UK
- Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, NE1 3BZ UK
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Kristiansen S, Friis-Hansen L. Validation of plasma thyroxine and triiodothyronine methods on the ADVIA Centaur ® XP. Scand J Clin Lab Invest 2019; 79:43-49. [PMID: 30777783 DOI: 10.1080/00365513.2019.1571624] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 12/28/2018] [Accepted: 01/15/2019] [Indexed: 06/09/2023]
Abstract
Standardization programs for thyroid hormones have revealed bias between immunochemical methods and the reference method ED-ID-LC/MS. Lack of standardization between methods, suboptimal reference intervals and replacement of serum with plasma may compromise the capability of the immunochemical thyroid methods to diagnose thyroid disease. To accommodate the demand for faster turn-around times for laboratory replies, we replaced serum with plasma on some serum CE marked thyroid methods. This forced us to do on-board analytical correction for the plasma total T4 (TT4) method on ADVIA Centaur® XP. We, next, validated the capability of the ADVIA Centaur® XP thyroid methods on plasma by (1) first carrying out a prospective method comparison with the ED-ID-LC/MS reference method using collected plasma samples, (2) we verified the clinical reference intervals by analyzing collected plasma samples from healthy individuals, and (3) retrospectively compared laboratory results from two different time periods using serum TT4 and serum total triiodothyronine (TT3) versus plasma free thyroxine (FT4) and plasma TT3, respectively, to diagnose thyroid disease. The plasma FT4 method displayed a negative concentration-dependent bias against the reference method. This bias was apparently counteracted by a fitted reference interval for the plasma FT4 method. Indeed, overt hyperthyroid disease was found in 1.0% and 1.1% of the cases using serum and plasma and overt hypothyroid condition were in 1.3% and 0.6% of the cases using serum and plasma, respectively. In conclusion, the ADVIA Centaur® XP FT4 method displayed a negative bias at high plasma FT4 concentrations against the reference method, but the diagnostic performance was not compromised due to a fitted reference interval.
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Affiliation(s)
- Søren Kristiansen
- a Department of Clinical Biochemistry, North Zealand Hospital , University of Copenhagen , Hilleroed , Denmark
| | - Lennart Friis-Hansen
- a Department of Clinical Biochemistry, North Zealand Hospital , University of Copenhagen , Hilleroed , Denmark
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Lillevang-Johansen M, Abrahamsen B, Jørgensen HL, Brix TH, Hegedüs L. Over- and Under-Treatment of Hypothyroidism Is Associated with Excess Mortality: A Register-Based Cohort Study. Thyroid 2018; 28:566-574. [PMID: 29631518 DOI: 10.1089/thy.2017.0517] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE This study investigated the association between hypothyroidism and mortality in both treated and untreated hypothyroid patients, and the consequences of over- and under-treatment with respect to mortality. PATIENTS AND METHODS This was a register-based cohort study of 235,168 individuals who had at least one serum thyrotropin (TSH) during 1995-2011 (median follow-up 7.2 years). Hypothyroidism was defined as at least two measurements of TSH >4.0 mIU/L within a half year spaced by at least 14 days, or one measurement of TSH >4.0 mIU/L and two filled prescriptions of levothyroxine the following year. All-cause mortality rates were calculated using multivariable Cox regression analysis adjusted for age, sex, and comorbidities using the Charlson Comorbidity Index. RESULTS Mortality was increased in untreated hypothyroid individuals (n = 673; hazard ratio [HR] = 1.46 [confidence interval (CI) 1.26-1.69]; p < 0.001) compared to euthyroid controls. Results remained significant even when subdividing according to mild (TSH >4.0 mIU/L and ≤10 mIU/L; p < 0.001) and marked hypothyroidism (TSH >10 mIU/L; p = 0.002). Mortality was increased in both treated and untreated hypothyroid individuals for each six months a patient had increased TSH (HR = 1.05 [CI 1.02-1.07], p < 0.0001, and HR = 1.05 [CI 1.02-1.07], p = 0.0009, respectively). In patients who received levothyroxine, the HR for mortality increased by a factor 1.18 ([CI 1.15-1.21]; p < 0.0001) for each six months a patient exhibited decreased TSH. This finding was essentially unchanged after stratification by disease severity (mild or marked hypothyroidism) and age (older and younger than 65 years). CONCLUSIONS Mortality was increased in untreated but not in treated hypothyroid individuals, independently of age and severity of hypothyroidism. Duration of decreased TSH in treated individuals had a greater impact on mortality than did duration of elevated TSH. These results stress the need for close monitoring of treatment in individuals receiving thyroid hormone replacement therapy.
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Affiliation(s)
- Mads Lillevang-Johansen
- 1 Department of Endocrinology and Metabolism, Odense University Hospital , Odense, Denmark
- 2 Institute of Clinical Research, University of Southern Denmark , Odense, Denmark
| | - Bo Abrahamsen
- 2 Institute of Clinical Research, University of Southern Denmark , Odense, Denmark
- 3 Odense Patient data Explorative Network OPEN, University of Southern Denmark , Odense, Denmark
- 4 Department of Medicine, Holbæk Hospital , Holbæk, Denmark
| | - Henrik Løvendahl Jørgensen
- 5 Department of Clinical Biochemistry, Hvidovre Hospital , Copenhagen, Denmark
- 6 Department of Clinical Medicine, University of Copenhagen , Denmark
| | - Thomas Heiberg Brix
- 1 Department of Endocrinology and Metabolism, Odense University Hospital , Odense, Denmark
| | - Laszlo Hegedüs
- 1 Department of Endocrinology and Metabolism, Odense University Hospital , Odense, Denmark
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Aminorroaya A, Meamar R, Amini M, Feizi A, Tabatabae A, Faghih Imani E. Incidence of thyroid dysfunction in an Iranian adult population: the predictor role of thyroid autoantibodies: results from a prospective population-based cohort study. Eur J Med Res 2017. [PMID: 28637498 PMCID: PMC5480126 DOI: 10.1186/s40001-017-0260-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Background The prevalence of thyroid dysfunction is high in Isfahan, an area of iodine sufficient in Iran. The aim of this study is to investigate the incidence of thyroid dysfunctions in adults of metropolitan Isfahan and to determine the role of thyroid autoantibodies. Methods In a population-based cohort study in 2006–2011, we measured TSH, T4, T3, thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) in 618 out of 2254 people who were euthyroid in 2006. The incidence rates per 1000 person-year (pr) were calculated. The odds ratio (OR), relative risk (RR), and 95% confidence interval (95% CI) were calculated based on logistic regression to quantify the potential predictors of thyroid dysfunction. The receiver-operator characteristic (ROC) analysis along with area under the curve (AUC) was used to determine the optimal cutoff values for baseline TPOAb and TgAb as predictors of thyroid dysfunction. Results Within a 6-year follow-up, the incidence rate of hypothyroidism was 3.3 in women and 2.1 in men while the incidence rate of hyperthyroidism was 3.8 in women and none in men per 1000 (person-year). A cutoff value of TPOAb at 38 IU/mL was obtained to differentiate the patients with hypothyroidism and hyperthyroidism, with specificity of 0.75 and sensitivity of 0.76, and AUC (CI 95%) of 0.882 (0.743–1.02), P = 0.01 and 0.817 (0.600–1.035) P = 0.033, respectively. There is a statistically significant association of hypothyroidism and hyperthyroidism with positive TPOAb [RR (CI 95%): 1.99 (1.27–3.13) and 2.20 (1.23–3.95), respectively]. Conclusions The incidence rate of thyroid dysfunction is high in Isfahan, and higher TPOAb concentration is its strong predictor.
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Affiliation(s)
- Ashraf Aminorroaya
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Sedigheh Tahereh Research Complex, Khorram Street, Isfahan, 8187698191, Iran.
| | | | - Massoud Amini
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Sedigheh Tahereh Research Complex, Khorram Street, Isfahan, 8187698191, Iran
| | - Awat Feizi
- Isfahan Endocrine and Metabolism Research Center, Isfahan, Iran.,Department of Biostatistics and Epidemiology, School of Public Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | | | - Elham Faghih Imani
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Sedigheh Tahereh Research Complex, Khorram Street, Isfahan, 8187698191, Iran
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Aminorroaya A, Meamar R, Amini M, Feizi A, Nasri M, Tabatabaei A, Faghihimani E. The TSH levels and risk of hypothyroidism: Results from a population based prospective cohort study in an Iranian adult's population. Eur J Intern Med 2017; 41:55-61. [PMID: 28111157 DOI: 10.1016/j.ejim.2016.12.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 12/19/2016] [Accepted: 12/22/2016] [Indexed: 10/20/2022]
Abstract
OBJECTIVE The aim of current study was to assess the relationship between serum TSH levels and hypothyroidism risk in the euthyroid population. METHODS In a population-based cohort study, a total of 615 individuals with a normal baseline TSH, from of total population (n=2254) in 2006, were followed up for 6years. TSH, total T4, thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TgAb) were measured. The relative risk (RR) and 95% confidence interval (95%CI) were calculated based on logistic regression. The Receiver Operating Characteristic (ROC) analysis along with area under the curve (AUC) was used to prediction of future hypothyroidism. RESULTS TSH level in 2006 was a significant predictor for overt hypothyroidism, in the total population (RR=3.5) and female (RR=1.37) (all, P value<0.05). A cutoff value of TSH at 2.05mIU/L [AUC: (CI95 %), 0.68 (0.44-0.92; P=0.05)] was obtained for differentiating the patients with overt hypothyroidism from euthyroid. However, this cut off was not observed when we included only negative TPO and TgAbs people in 2006. The RR of hypothyroidism increased gradually when TSH level increased from 2.06-3.6mIU/L to >3.6mIU/L in the total population and both sexes. In women, the risk of overt hypothyroidism was significantly higher in subjects with TSH above 3.6 than those subject with THS levels≤2.05 [RR: (CI95 %), 20.57(2.-207.04), P value<0.05]. CONCLUSION A cutoff value of TSH at 2.05mIU/L could predict the development of overt hypothyroidism in future. However, it was not applicable for people with negative TPOAb and negative TgAb.
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Affiliation(s)
- Ashraf Aminorroaya
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Rokhsareh Meamar
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Massoud Amini
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran.
| | - Awat Feizi
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran; Department of Biostatistics and Epidemiology, School of Public Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | | | - Azamosadat Tabatabaei
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Elham Faghihimani
- Isfahan Endocrine and Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
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16
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Mirjanic-Azaric B, Avram S, Stojakovic-Jelisavac T, Stojanovic D, Petkovic M, Bogavac-Stanojevic N, Ignjatovic S, Stojanov M. Direct Estimation of Reference Intervals for Thyroid Parameters in the Republic of Srpska. J Med Biochem 2017; 36:137-144. [PMID: 28680357 PMCID: PMC5471646 DOI: 10.1515/jomb-2017-0008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 02/03/2017] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The aim of this study was to determine the reference values for thyrotropin (TSH), thyroid hormones (total and free thyroxine, T4 and fT4; total and free triiodothyronine, T3 and fT3), thyroglobulin (Tg) and thyroid antibodies (thyroid peroxidase, TPOAb and thyroglobulin antibody, TgAb) in the population of the Republic of Srpska. METHODS A total of 250 euthyroid subjects were enrolled in this study. A direct method for choosing reference subjects was used to establish reference intervals. The hormones and thyroid antibodies were measured by an electrochemiluminescence immunoassay method (ECLIA, Roche Diagnostics, Mannheim, Germany). We calculated the reference intervals by MedCalc, version 12.1.4.0 (MedCalc software, Belgium) as recommended by the IFCC (CLSI C28-A3). RESULTS Using guidelines recommended by the National Academy of Clinical Biochemistry (NACB) and based on standard statistical approaches, the reference intervals derived for TSH, fT4, T4, fT3, T3 were 0.75-5.32 mIU/L, 12.29-20.03 pmol/L, 73.49-126,30 nmol/L, 4.11-6.32 pmol/L, 1.15-2.32 nmol/L and for Tg, TPOAb, TgAb were 3.63-26.00 μg/L, <18.02 mIU/L, < 98.00 mIU/L, respectively. We found a significant difference (p<0.05) in TSH and fT3 values between different age groups as well as in T4, fT4 and fT3 values between ge nder groups. CONCLUSIONS The established reference values for the population of the Republic of Srpska were significantly different from the values recommended by the manufacturer of reagents (Roche Diagnostics). Our results showed that a laboratory needs to establish its own reference values in order to set up a proper diagnosis, as well as to treat patients successfully.
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Affiliation(s)
- Bosa Mirjanic-Azaric
- University Clinical Centre of the Republic of SrpskaBanja Luka, Bosnia and Herzegovina, Serbia
| | - Sanja Avram
- University Clinical Centre of the Republic of SrpskaBanja Luka, Bosnia and Herzegovina, Serbia
| | | | - Darja Stojanovic
- Health Centre Laktasi, the Republic of Srpska, Bosnia and HerzegovinaSerbia
| | - Mira Petkovic
- Institute for Sport and Occupational Medicine Banja Luka, Bosnia and HerzegovinaSerbia
| | | | - Svetlana Ignjatovic
- Institute of Medical Biochemistry, Faculty of Pharmacy, University of Belgrade, Serbia
- Center for Medical Biochemistry, Clinical Center of Serbia, Belgrade, Serbia
| | - Marina Stojanov
- Institute of Medical Biochemistry, Faculty of Pharmacy, University of Belgrade, Serbia
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17
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Pereira AM. Long-term effects of treatment of pituitary adenomas. HANDBOOK OF CLINICAL NEUROLOGY 2016; 124:361-71. [PMID: 25248599 DOI: 10.1016/b978-0-444-59602-4.00024-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Pituitary adenomas can be treated effectively in the vast majority of cases. After successful treatment for pituitary disease, many patients still report reduced quality of life in the presence of persistent morbidity and (slightly) increased mortality. At present, there is an increasing awareness that in many cases long-term remission of functioning or nonfunctioning adenomas does not equal cure. The causes are most probably multifactorial. Hypopituitarism, intrinsic imperfections of surgical or endocrine replacement therapy, but also persistent effects of treatment and of previous hormone excess on the central nervous system all affect long-term morbidity, general well-being, and mortality. This implies that treatment goals for patients with pituitary adenomas will shift from long-term cure to long-term care. Further research is therefore needed to get more insight into each of these factors of influence, such as the extent of reversibility of hormone excess syndromes on cardiovascular risk and behavior. The fact that coping strategies, despite long-term remission, are altered and illness perceptions are affected strongly suggests that long-term care should incorporate self-management interventions that might help to improve quality of life for patients.
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Affiliation(s)
- Alberto M Pereira
- Department of Endocrinology and Center for Endocrine Tumors, Leiden University Medical Center, Leiden, The Netherlands.
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18
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Rønjom MF, Brink C, Bentzen SM, Hegedüs L, Overgaard J, Petersen JBB, Primdahl H, Johansen J. External validation of a normal tissue complication probability model for radiation-induced hypothyroidism in an independent cohort. Acta Oncol 2015; 54:1301-9. [PMID: 26248025 DOI: 10.3109/0284186x.2015.1064160] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND A normal tissue complication probability (NTCP) model for radiation-induced hypothyroidism (RIHT) was previously derived in patients with squamous cell carcinoma of the head and neck (HNSCC) discerning thyroid volume (Vthyroid), mean thyroid dose (Dmean), and latency as predictive factors. The purpose of this study was to test the performance of this model in an independent cohort of patients receiving primary radiotherapy (RT) for HNSCC. MATERIAL AND METHODS A validation cohort of 198 patients with HNSCC was included after plasma thyrotropin (TSH) assessment. RIHT was defined as TSH > 4.0 mU/l from blood samples obtained during follow-up. A new mixture NTCP model was developed from the validation cohort after multivariable analysis. Due to only one follow-up TSH assessment in the validation cohort, the time factor derived from the original cohort was fixed in a mixture model and applied for the NTCP validation. Association between model predictions of the initial model and observed clinical outcome in the validation cohort was investigated by applying the previous model (Vthyroid, Dmean and time) on the new cohort and comparing it to the clinical outcome. RESULTS Both Dmean and Vthyroid were confirmed as significant risk factors for RIHT in the validation cohort, odds ratio (OR) 1.19 (1.1-1.37) and OR 0.75 (0.57-0.9), respectively. A small difference in overall probability of RIHT was observed between the cohorts, further analysis indicated this to be related to less frequent blood tests in the validation cohort relative to the original cohort. However, Pearson's correlation coefficients between model and clinical outcome were high: r = 0.97 estimated by the original model versus the original cohort, and r = 0.97 estimated by the original model versus the new cohort. CONCLUSION Dmean and Vthyroid were significant predictors of RIHT in both cohorts. The original NTCP model demonstrated external validity owing to high Pearson's correlation coefficients between estimated and observed incidence rates of RIHT in the original as well as in the validation cohort. This model may facilitate clinically relevant estimations of RIHT after RT to the neck.
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Affiliation(s)
- Marianne F Rønjom
- a Department of Oncology , Odense University Hospital , Odense , Denmark
- b Institute of Clinical Research, University of Southern Denmark , Odense , Denmark
| | - Carsten Brink
- b Institute of Clinical Research, University of Southern Denmark , Odense , Denmark
- c Laboratory of Radiation Physics, Odense University Hospital , Odense , Denmark
| | - Søren M Bentzen
- d Division of Biostatistics and Bioinformatics, University of Maryland Greenebaum Cancer Center , Baltimore , USA
- e Department of Epidemiology and Public Health , University of Maryland School of Medicine , Baltimore , USA
| | - Laszlo Hegedüs
- b Institute of Clinical Research, University of Southern Denmark , Odense , Denmark
- f Department of Endocrinology and Metabolism , Odense University Hospital , Odense , Denmark
| | - Jens Overgaard
- g Department of Experimental Clinical Oncology , Aarhus University Hospital , Aarhus , Denmark
| | - Jørgen B B Petersen
- h Department of Medical Physics , Aarhus University Hospital , Aarhus , Denmark
| | - Hanne Primdahl
- i Department of Oncology , Aarhus University Hospital , Aarhus , Denmark
| | - Jørgen Johansen
- a Department of Oncology , Odense University Hospital , Odense , Denmark
- b Institute of Clinical Research, University of Southern Denmark , Odense , Denmark
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Kristensen B, Hegedüs L, Lundy SK, Brimnes MK, Smith TJ, Nielsen CH. Characterization of Regulatory B Cells in Graves' Disease and Hashimoto's Thyroiditis. PLoS One 2015; 10:e0127949. [PMID: 26016954 PMCID: PMC4446335 DOI: 10.1371/journal.pone.0127949] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2014] [Accepted: 04/21/2015] [Indexed: 12/21/2022] Open
Abstract
A hallmark of regulatory B cells is IL-10 production, hence their designation as IL-10+ B cells. Little is known about the ability of self-antigens to induce IL-10+ B cells in Graves’ disease (GD), Hashimoto’s thyroiditis (HT), or other autoimmune disease. Here we pulsed purified B cells from 12 HT patients, 12 GD patients, and 12 healthy donors with the thyroid self-antigen, thyroglobulin (TG) and added the B cells back to the remaining peripheral blood mononuclear cells (PBMCs). This procedure induced IL-10+ B-cell differentiation in GD. A similar tendency was observed in healthy donors, but not in cells from patients with HT. In GD, B cells primed with TG induced IL-10-producing CD4+ T cells. To assess the maximal frequency of inducible IL-10+ B cells in the three donor groups PBMCs were stimulated with PMA/ionomycin. The resulting IL-10+ B-cell frequency was similar in the three groups and correlated with free T3 levels in GD patients. IL-10+ B cells from both patient groups displayed CD25 or TIM-1 more frequently than did those from healthy donors. B-cell expression of two surface marker combinations previously associated with regulatory B-cell functions, CD24hiCD38hi and CD27+CD43+, did not differ between patients and healthy donors. In conclusion, our findings indicate that autoimmune thyroiditis is not associated with reduced frequency of IL-10+ B cells. These results do not rule out regulatory B-cell dysfunction, however. The observed phenotypic differences between IL-10+ B cells from patients and healthy donors are discussed.
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Affiliation(s)
- Birte Kristensen
- Institute for Inflammation Research, Department of Infectious Diseases and Rheumatology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark
| | - Laszlo Hegedüs
- Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark
| | - Steven K. Lundy
- Division of Rheumatology, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States of America
| | - Marie K. Brimnes
- Institute for Inflammation Research, Department of Infectious Diseases and Rheumatology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Terry J. Smith
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center and Division of Metabolism, Endocrinology, and Diabetes, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI, United States of America
| | - Claus H. Nielsen
- Institute for Inflammation Research, Department of Infectious Diseases and Rheumatology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
- * E-mail:
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20
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Abrahamsen B, Jørgensen HL, Laulund AS, Nybo M, Bauer DC, Brix TH, Hegedüs L. The excess risk of major osteoporotic fractures in hypothyroidism is driven by cumulative hyperthyroid as opposed to hypothyroid time: an observational register-based time-resolved cohort analysis. J Bone Miner Res 2015; 30:898-905. [PMID: 25431028 DOI: 10.1002/jbmr.2416] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 11/11/2014] [Accepted: 11/27/2014] [Indexed: 11/10/2022]
Abstract
The long-term relationship between hypothyroidism and fracture risk is challenging to dissect because of the modifying influence of subsequent thyroxine replacement with the potential for excessive replacement doses. We studied changes in serum thyrotropin concentration (TSH) over time and association with fracture risk in real-world patients presenting with elevated TSH. All TSH determinations were done in the same laboratory, which served all hospitals and general practices. The study population consisted of all adults with a first measurement of TSH >4.0 mIU/L (n = 8414) or normal TSH (n = 222,138; comparator). We used a Cox proportional hazards analysis incorporating additional time-dependent covariates to represent initiation of thyroxine replacement and cumulative number of periods with high versus low TSH after index date with a mean follow-up of 7.2 years. Elevated baseline TSH was not associated with an increased risk of hip fracture (HR 0.90; 95% CI, 0.80 to 1.02) or major osteoporotic fractures (HR 0.97; 95% CI, 0.90 to 1.05), nor was subsequent thyroxine prescription predictive of increased risk of fractures. The number of subsequent 6-month periods with low TSH-suggesting excessive thyroxine dosing-was significantly associated with increased risk of both hip fracture (HR 1.09; 95% CI, 1.04 to 1.15) and major osteoporotic fracture (HR 1.10; 95% CI, 1.06 to 1.14). When gender- and age-stratified analyses for major osteoporotic fractures were undertaken, hyperthyroid time was identified as a predictor of fracture risk in postmenopausal women whereas hypothyroid time predicted increased fracture risk in men below age 75 years. In conclusion, among patients who present with an elevated TSH, the long-term risk of hip and other osteoporotic fractures is strongly related to the cumulative duration of periods with low TSH-likely from excessive replacement. An independent effect of elevated TSH could only be observed in young and middle-aged men, suggesting gender-discrepant consequences on risk.
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Affiliation(s)
- Bo Abrahamsen
- Odense Patient data Explorative Network (OPEN), Institute of Clinical Research University of Southern Denmark, Odense, Denmark; Department of Medicine M, Research Centre for Ageing and Osteoporosis, Glostrup Hospital, Glostrup, Denmark
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Laulund AS, Nybo M, Brix TH, Abrahamsen B, Jørgensen HL, Hegedüs L. Duration of thyroid dysfunction correlates with all-cause mortality. the OPENTHYRO Register Cohort. PLoS One 2014; 9:e110437. [PMID: 25340819 PMCID: PMC4207745 DOI: 10.1371/journal.pone.0110437] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 09/20/2014] [Indexed: 01/01/2023] Open
Abstract
Introduction and Aim The association between thyroid dysfunction and mortality is controversial. Moreover, the impact of duration of thyroid dysfunction is unclarified. Our aim was to investigate the correlation between biochemically assessed thyroid function as well as dysfunction duration and mortality. Methods Register-based follow-up study of 239,768 individuals with a serum TSH measurement from hospitals and/or general practice in Funen, Denmark. Measurements were performed at a single laboratory from January 1st 1995 to January 1st 2011. Cox regression was used for mortality analyses and Charlson Comorbidity Index (CCI) was used as comorbidity score. Results Hazard ratios (HR) with 95% confidence intervals (CI) for mortality with decreased (<0.3 mIU/L) or elevated (>4.0 mIU/L) levels of TSH were 2.22; 2.14–2.30; P<0.0001 and 1.28; 1.22–1.35; P<0.0001, respectively. Adjusting for age, gender, CCI and diagnostic setting attenuated the risk estimates (HR 1.23; 95% CI: 1.19–1.28; P<0.0001, mean follow-up time 7.7 years, and HR 1.07; 95% CI: 1.02–1.13; P = 0.004, mean follow-up time 7.2 years) for decreased and elevated values of TSH, respectively. Mortality risk increased by a factor 1.09; 95% CI: 1.08–1.10; P<0.0001 or by a factor 1.03; 95% CI: 1.02–1.04; P<0.0001 for each six months a patient suffered from decreased or elevated TSH, respectively. Subdividing according to degree of thyroid dysfunction, overt hyperthyroidism (HRovert 1.12; 95% CI: 1.06–1.19; P<0.0001), subclinical hyperthyroidism (HRsubclinical 1.09; 95% CI: 1.02–1.17; P = 0.02) and overt hypothyroidism (HRovert 1.57; 95% CI: 1.34–1.83; P<0.0001), but not subclinical hypothyroidism (HRsubclinical 1.03; 95% CI: 0.97–1.09; P = 0.4) were associated with increased mortality. Conclusions and Relevance In a large-scale, population-based cohort with long-term follow-up (median 7.4 years), overt and subclinical hyperthyroidism and overt but not subclinical hypothyroidism were associated with increased mortality. Excess mortality with increasing duration of decreased or elevated serum TSH suggests the importance of timely intervention in individuals with thyroid dysfunction.
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Affiliation(s)
- Anne Sofie Laulund
- Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark
| | - Mads Nybo
- Department of Clinical Biochemistry and Pharmacology, Odense University Hospital, Odense, Denmark
| | - Thomas Heiberg Brix
- Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark
| | - Bo Abrahamsen
- Odense Patient Data Explorative Network OPEN, University of Southern Denmark, Odense, Denmark; Institute of Clinical Research, Odense, Denmark; Research Centre for Ageing and Osteoporosis, Department of Medicine M, Glostrup Hospital, Copenhagen, Denmark
| | | | - Laszlo Hegedüs
- Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark
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Brix TH, Hegedüs L, Weetman AP, Kemp HE. Pendrin and NIS antibodies are absent in healthy individuals and are rare in autoimmune thyroid disease: evidence from a Danish twin study. Clin Endocrinol (Oxf) 2014; 81:440-4. [PMID: 24612086 DOI: 10.1111/cen.12434] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Revised: 01/28/2014] [Accepted: 02/14/2014] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Antibodies against thyroglobulin, thyroid peroxidase and the TSH receptor are accepted as pathophysiological and diagnostic biomarkers in autoimmune thyroid disease (AITD). In contrast, the prevalence, aetiology and clinical relevance of autoantibodies against the human sodium-iodine symporter (NISAb) and pendrin (PenAb) remain unclear. The objectives of the study were to investigate the presence of NISAb and PenAb in Danish twins, with and without AITD, to study whether the published variations in NISAb and PenAb frequencies were related to differences in methodology or study populations, and to evaluate whether the presence of NISAb or PenAb most likely results from genetic or nongenetic factors. METHODS Sera from 93 patients with AITD and 230 healthy controls were evaluated for NISAb and PenAb using radioligand binding assays (RBA). RESULTS Patients with AITD had a higher prevalence than the controls: NISAb: 17% vs 0% (P < 0·001) and PenAb: 11% vs 0% (P < 0·001). Subdividing according to cause of AITD yielded similar results: 20% (11/56) of patients with Graves' disease (GD) and 14% (5/37) of patients with Hashimoto's thyroiditis (HT) had NISAb, (P < 0·05, vs control population). Seven of 56 (13%) patients with GD and three of 37 (8%) patients with HT had PenAb (P < 0·05 vs control population). No twin pairs were concordant for NISAb or PenAb, not even among twin pairs concordant for AITD. CONCLUSIONS In accord with studies using the same RBAs, the frequency of NISAb and PenAb was low in Danish patients with AITD and absent in healthy individuals, suggesting that differences between studies rely on assay differences. The skewed distribution of NISAb and PenAb within AITD concordant twin pairs suggests that NISAb and PenAb are likely attributable to the effects of environmental factors acting in genetic susceptible individuals.
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Affiliation(s)
- Thomas H Brix
- Department of Endocrinology and Metabolism, Odense University Hospital, Odense, UK
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Selmer C, Olesen JB, Hansen ML, von Kappelgaard LM, Madsen JC, Hansen PR, Pedersen OD, Faber J, Torp-Pedersen C, Gislason GH. Subclinical and overt thyroid dysfunction and risk of all-cause mortality and cardiovascular events: a large population study. J Clin Endocrinol Metab 2014; 99:2372-82. [PMID: 24654753 DOI: 10.1210/jc.2013-4184] [Citation(s) in RCA: 169] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
CONTEXT Thyroid dysfunction has been associated with both increased all-cause and cardiovascular mortality, but limited data are available on mild thyroid dysfunction and cause-specific mortality. OBJECTIVE The objective of the study was to examine the risk of all-cause mortality, major adverse cardiovascular events (MACEs), and cause-specific events in subjects with overt and subclinical thyroid dysfunction. DESIGN This was a retrospective cohort study. SETTING AND PARTICIPANTS Participants in the study were subjects who underwent thyroid blood tests, without prior thyroid disease, consulting their general practitioner in 2000-2009 in Copenhagen, Denmark. MAIN OUTCOME MEASURE All-cause mortality, MACEs, and cause-specific events identified in nationwide registries were measured. RESULTS A total of 47 327 (8.4%) deaths occurred among 563 700 included subjects [mean age 48.6 (SD ± 18.2) y; 39% males]. All-cause mortality was increased in overt and subclinical hyperthyroidism [age adjusted incidence rates of 16 and 15 per 1000 person-years, respectively; incidence rate ratios (IRRs) 1.25 [95% confidence interval (CI) 1.15-1.36] and 1.23 (95% CI 1.16-1.30)] compared with euthyroid (incidence rate of 12 per 1000 person-years). Risk of MACEs was elevated in overt and subclinical hyperthyroidism [IRRs 1.16 (95% CI 1.05-1.27) and 1.09 (95% CI 1.02-1.16)] driven by heart failure [IRRs 1.14 (95% CI 0.99-1.32) and 1.20 (95% CI 1.10-1.31)]. A reduction of all-cause mortality was observed in subclinical hypothyroidism with TSH of 5-10 mIU/L [IRR 0.92 (95% CI 0.86-0.98)]. CONCLUSIONS Heart failure is the leading cause of an increased cardiovascular mortality in both overt and subclinical hyperthyroidism. Subclinical hypothyroidism with TSH 5-10 mIU/L might be associated with a lower risk of all-cause mortality.
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Affiliation(s)
- Christian Selmer
- Department of Cardiology (C.S., J.B.O., M.L.H., P.R.H., G.H.G.), Gentofte University Hospital, DK-2900 Hellerup, Denmark; Department of Endocrinology (C.S., J.F.), Herlev University Hospital, DK-2730 Herlev, Denmark; Copenhagen General Practitioners Laboratory (J.C.M.), DK-2100 Copenhagen, Denmark; Faculty of Health and Medical Sciences (J.F., G.H.G.), University of Copenhagen, DK-2200 Copenhagen, Denmark; Department of Cardiology (O.D.P.), Roskilde University Hospital, DK-4000 Roskilde, Denmark; Institute of Health, Science, and Technology (C.T.-P.), Aalborg University, DK-9220 Aalborg, Denmark; and National Institute of Public Health (L.M.v.K., G.H.G.), University of Southern Denmark, DK-1353 Copenhagen, Denmark
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Roelfsema F, Pijl H, Kok P, Endert E, Fliers E, Biermasz NR, Pereira AM, Veldhuis JD. Thyrotropin secretion in healthy subjects is robust and independent of age and gender, and only weakly dependent on body mass index. J Clin Endocrinol Metab 2014; 99:570-8. [PMID: 24276453 DOI: 10.1210/jc.2013-2858] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
CONTEXT Studies of the influence of sex, age, and body weight on TSH secretion are not unanimous. Most reports are based on a single TSH measurement; studies using frequent blood sampling are scarce and include a limited number of selected subjects. OBJECTIVE The goal was to investigate TSH dynamics in 117 healthy adults. METHODS TSH was measured by a sensitive immunofluorometric assay. Secretion parameters were quantified by automated deconvolution, approximate entropy [ApEn], spikiness, and diurnal properties. RESULTS Mean age was 43 years (range, 22-77 y). Mean body mass index (BMI) was 26.8 kg/m(2) (range, 18.3-39.4 kg/m(2)). Daily TSH secretion was 45.4 mU/L (range, 8.0-207 mU/L). There were no sex differences in secretion parameters, including pulse frequency; basal, pulsatile, and total secretion; pulse mode; half life; pulse regularity; ApEn; spikiness; and nycthemeral properties. BMI was positively related to basal secretion. Total secretion correlated negatively with free T₄ (R = 0.225; P = .018). The onset of the nocturnal surge was delayed by increasing BMI and advanced by increasing age. ApEn and spikiness correlated positively with age, especially in men. The 9 am sample correlated strongly with the total 24-hour secretion, explaining two-thirds of the variability. CONCLUSION This study shows that the 24-hour TSH secretion in healthy volunteers is stable and robust and not influenced by sex, BMI, and age. ApEn in the elderly, especially men, is increased, pointing to a less tight feedback control. Furthermore, aging is associated with advance shifting of the TSH rhythm, which is a phenomenon also observed in other biological rhythms.
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Affiliation(s)
- Ferdinand Roelfsema
- Department of Endocrinology and Metabolism (F.R., H.P., P.K., N.R.B., A.M.P.), Leiden University Medical Center, 2333 ZA Leiden, The Netherlands; Department of Endocrinology (E.E., E.F.), Amsterdam Medical Center, University of Amsterdam, 1105 AZ Amsterdam, The Netherlands; and Endocrine Research Unit (J.D.V.), Mayo Clinic College of Medicine, Rochester, Minnesota 55905
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Kutluturk F, Yildirim B, Ozturk B, Ozyurt H, Bekar U, Sahin S, Akturk Y, Akbas A, Cetin I, Etikan I. The reference intervals of thyroid stimulating hormone in healthy individuals with normal levels of serum free thyroxine and without sonographic pathologies. Endocr Res 2014; 39:56-60. [PMID: 24067097 DOI: 10.3109/07435800.2013.824896] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
INTRODUCTION The aim of the present study was to investigate the reference intervals for thyroid stimulating hormone (TSH) in healthy individuals with normal levels of serum free thyroxine (fT4) and without sonographic pathologies, and determine the effects of age, gender, and residence on the TSH reference intervals. SUBJECTS AND METHODS This research was a population-based study conducted in 70 regions. The random sampling method was used to select the 1095 subjects of the study among inhabitants aged 18 and above. Patients who had a previous history of thyroid disease and had been taking medication were excluded from the study as this may have affected their fT4 or TSH levels. In addition, subjects who had serum fT4 without a reference range and abnormal ultrasonography findings were also excluded. A total of 408 subjects were used for establishing the reference intervals for TSH. RESULTS The data for TSH in the study group were not normally distributed according to the Kolmogorov-Smirnov index. The geometric mean was 1.62 mIU/L, the median was 1.40 mIU/L, and the 95% reference intervals were 0.38-4.22 mIU/L. The median TSH level was higher in females compared to males (p < 0.05). In the female subjects 2.5th percentile of TSH was lower and 97.5th percentile was higher than those of males. The reference intervals of TSH were of lower values in subjects over 50 years old (p < 0.001). DISCUSSION Studies suggest that determination of the TSH reference intervals may differ due to environmental influences or due to age, gender, and race. It is suggested that the lower limit of normal TSH for the adult Turkish population would be 0.38 mIU/L and the upper limit similar to the traditional value of 4.2 mIU/L. If each clinician uses their population-specific reference interval for TSH, thyroid function abnormalities can be accurately estimated.
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Amouzegar A, Delshad H, Mehran L, Tohidi M, Khafaji F, Azizi F. Reference limit of thyrotropin (TSH) and free thyroxine (FT4) in thyroperoxidase positive and negative subjects: a population based study. J Endocrinol Invest 2013; 36:950-4. [PMID: 23873252 DOI: 10.3275/9033] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND Current reference values for thyroid function tests are based on data from different ethnicities and geographical areas. The aim of the present study was to determine reference intervals for thyrotropin (TSH) and free T4 (FT4), based on the criteria of the National Academy of Clinical Biochemistry (NACB) in an Iranian population. MATERIAL AND METHODS This study was conducted within the framework of Tehran Thyroid Study (TTS), an ongoing prospective cohort of 5704 randomly selected individuals, age ≥ 20 yr. A total of 2199 individuals (43.3% male, 56.7% female), based on NACB criteria were included in this study. Reference limit analysis was performed for the negative thyroid peroxidase antibody (TPOAb) group. RESULTS After applying all exclusion criteria except TPOAb positivity (10.5%), data of 2459 participants remained for analysis. Of these, 953 (43.3%) were males and 1246 (56.7%) were females; the mean ± SD age was 43.53 ± 14.16 yr. The mean ± SD and median+IQR for TSH were 1.77 mU/l ± 1.24 and 1.46 (0.93-2.23) mU/l, respectively. The 2.5th and 97.5th percentiles TSH were 0.32 mU/l and 5.06 mU/l respectively. The mean ± SD and median (IQR) for FT4 for all negative TPOAb subjects were 1.19 ± 0.16 and 1.18 (1.08-1.31) ng/dl respectively. CONCLUSION Reference ranges for thyroid function tests need to be derived from national databases. This study determined age and sex specific TSH and FT4 reference ranges in a Tehranian population, which could eventually enable clinicians to classify patients more appropriately.
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Affiliation(s)
- A Amouzegar
- Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, I.R. Iran
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27
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Rønjom MF, Brink C, Bentzen SM, Hegedüs L, Overgaard J, Johansen J. Hypothyroidism after primary radiotherapy for head and neck squamous cell carcinoma: normal tissue complication probability modeling with latent time correction. Radiother Oncol 2013; 109:317-22. [PMID: 23891099 DOI: 10.1016/j.radonc.2013.06.029] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Revised: 06/17/2013] [Accepted: 06/20/2013] [Indexed: 01/07/2023]
Abstract
BACKGROUND AND PURPOSE To develop a normal tissue complication probability (NTCP) model of radiation-induced biochemical hypothyroidism (HT) after primary radiotherapy for head and neck squamous cell carcinoma (HNSCC) with adjustment for latency and clinical risk factors. PATIENTS AND METHODS Patients with HNSCC receiving definitive radiotherapy with 66-68Gy without surgery were followed up with serial post-treatment thyrotropin (TSH) assessment. HT was defined as TSH >4.0mU/l. Data were analyzed with both a logistic and a mixture model (correcting for latency) to determine risk factors for HT and develop an NTCP model based on mean thyroid dose (MTD) and thyroid volume. RESULTS 203 patients were included. Median follow-up: 25.1months. Five-year estimated risk of HT was 25.6%. In the mixture model, the only independent risk factors for HT were thyroid volume (cm(3)) (OR=0.75 [95% CI: 0.64-0.85], p<0.001) and MTD (Gy) (OR=1.12 [95% CI: 1.07-1.20], p<0.001). From the mixture NTCP-model individual dose constraints for a 25% risk of HT were 26, 38, 48 and 61Gy for thyroid volumes of 10, 15, 20 and 25cm(3), respectively. CONCLUSIONS Comparing the logistic and mixture models demonstrates the importance of latent-time correction in NTCP-modeling. Thyroid dose constraints in treatment planning should be individualized based on thyroid volume.
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Affiliation(s)
- Marianne Feen Rønjom
- Department of Oncology, Odense University Hospital, Denmark; Institute of Clinical Research, University of Southern Denmark, Odense, Denmark.
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Management of thyroid peroxidase antibody euthyroid women in pregnancy: comparison of the american thyroid association and the endocrine society guidelines. J Thyroid Res 2013; 2013:542692. [PMID: 23738229 PMCID: PMC3666229 DOI: 10.1155/2013/542692] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Accepted: 03/27/2013] [Indexed: 01/27/2023] Open
Abstract
The presence of thyroid autoantibodies is relatively high in women of childbearing age. There is evidence that positive thyroperoxidase antibody even in euthyroid women may increase the risk of spontaneous and recurrent pregnancy loss and preterm delivery. However, the evidence is not enough to justify recommendation on the screening of pregnant women for thyroid autoantibodies or LT4 supplementation for reducing maternal or fetal complications. In this paper we reviewed the related evidence and compared the new guidelines of the American Thyroid Association and Endocrine Society with respect to the screening and management of positive thyroperoxidase antibody in euthyroid pregnant women. As there was no major contradiction or disagreement between the two guidelines, either one of two guidelines may be used by clinicians for the appropriate management of thyroid autoimmunity during pregnancy.
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Jalkanen A, Saraste M, Gfeller A, Surcel HM, Airas L. Increased thyroid autoimmunity among women with multiple sclerosis in the postpartum setting. Mult Scler 2013; 19:1734-42. [DOI: 10.1177/1352458513485148] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background: Multiple sclerosis (MS) patients are predisposed to thyroid abnormalities, but the risk for pregnancy-related thyroid pathology among MS patients has not been evaluated. Objectives: The objectives of this research are to prospectively evaluate the prevalence of thyroid autoimmunity among MS patients in relation to pregnancy, and to investigate its impact on pregnancy outcome, postpartum depression and fatigue. Methods: Forty-six pregnant MS patients underwent repeat testing for serum thyroid antibodies (Abs), clinical evaluation and thyroid hormone measurement. Results were compared to 35 age-matched healthy mothers. Results: At six months postpartum 35.3% of MS patients presented elevated levels of thyroid Abs compared to 5.7% of controls, p = 0.01. Mean thyroid Ab concentrations among MS patients were significantly reduced during pregnancy and returned to maximal levels at six months postpartum. The proportion of individuals with postpartum thyroid dysfunction did not differ significantly between MS patients and healthy controls (3.4% vs 2.9%, p = 1.00). Elevated thyroid Ab levels did not increase the risk for adverse pregnancy outcome, fatigue or postpartum depression. Conclusions: Considering the tendency of MS mothers to develop thyroid autoimmunity postpartum and in association to treatments, we recommend screening MS patients for thyroid dysfunction (TSH) during early pregnancy and after delivery.
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Affiliation(s)
- A Jalkanen
- Department of Neurology, Turku University Hospital, Finland
| | - M Saraste
- MediCity Research Laboratory, University of Turku, Finland
| | - A Gfeller
- Department of Neurology, Turku University Hospital, Finland
| | - HM Surcel
- Finnish Maternity Cohort, National Institute for Health and Welfare, Finland
| | - L Airas
- Department of Neurology, Turku University Hospital, Finland
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Marwaha RK, Tandon N, Ganie MA, Mehan N, Sastry A, Garg M, Bhadra K, Singh S. Reference range of thyroid function (FT3, FT4 and TSH) among Indian adults. Clin Biochem 2013; 46:341-5. [DOI: 10.1016/j.clinbiochem.2012.09.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 09/07/2012] [Accepted: 09/23/2012] [Indexed: 10/27/2022]
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Abstract
Reference ranges are a set of values that correctly include most of the subjects with characteristics similar to the reference group and exclude the others. When accurate, reference ranges aid physicians to interpret results of clinical measurements and thus establish diagnosis. However, obtaining accurate reference ranges is a very demanding procedure. This chapter provides basic definitions and theories as well as a step-by-step procedure for the analysis of reference values and determination of reference ranges of coagulation, focusing on quantitative clinical laboratory assays. Preanalytical and analytical factors as well as dependence on the age influencing reference values for coagulation assays and their transference are discussed.
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Affiliation(s)
- Oliver Speer
- Division of Haematology, University Children's Hospital, Zurich, Switzerland
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Cárdenas Roldán J, Amaya-Amaya J, Castellanos-de la Hoz J, Giraldo-Villamil J, Montoya-Ortiz G, Cruz-Tapias P, Rojas-Villarraga A, Mantilla RD, Anaya JM. Autoimmune thyroid disease in rheumatoid arthritis: a global perspective. ARTHRITIS 2012; 2012:864907. [PMID: 23209899 PMCID: PMC3505628 DOI: 10.1155/2012/864907] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 08/31/2012] [Indexed: 12/14/2022]
Abstract
Objective. To determine the prevalence and impact of autoimmune thyroid disease (AITD) in patients with rheumatoid arthritis (RA). Methods. Eight-hundred patients were included. The association between AITD and RA was analyzed was analyzed by bivariate and multivariate analysis. In addition, a literature review was done focusing on geographical variations. Results. In our cohort the prevalence of AITD was 9.8% while the presence of antibodies was 37.8% for antithyroperoxidase enzyme (TPOAb) and 20.8% for antithyroglobulin protein (TgAb). The presence of type 2 diabetes, thrombosis, abnormal body mass index, and a high educational level was positively associated with AITD. The literature review disclosed a geographical variation of AITD in RA ranging from 0.5% to 27%. Autoantibody prevalence ranges from 6% to 31% for TgAb, 5% to 37% for TPOAb, and from 11.4% to 32% for the presence of either of the two. Conclusion. AITD is not uncommon in RA and should be systematically assessed since it is a risk factor for developing diabetes and cardiovascular disease. These results may help to further study the common mechanisms of autoimmune diseases, to improve patients' outcome, and to define public health policies. An international consensus to accurately diagnose AITD is warranted.
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Affiliation(s)
- Jorge Cárdenas Roldán
- Center for Autoimmune Diseases Research (CREA), School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
| | - Jenny Amaya-Amaya
- Center for Autoimmune Diseases Research (CREA), School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
| | - Juan Castellanos-de la Hoz
- Center for Autoimmune Diseases Research (CREA), School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
| | - Juliana Giraldo-Villamil
- Center for Autoimmune Diseases Research (CREA), School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
| | - Gladys Montoya-Ortiz
- Center for Autoimmune Diseases Research (CREA), School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
| | - Paola Cruz-Tapias
- Center for Autoimmune Diseases Research (CREA), School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
- Doctoral Program in Biomedical Sciences, Universidad del Rosario, Bogota, Colombia
| | - Adriana Rojas-Villarraga
- Center for Autoimmune Diseases Research (CREA), School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
| | - Rubén D. Mantilla
- Center for Autoimmune Diseases Research (CREA), School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
| | - Juan-Manuel Anaya
- Center for Autoimmune Diseases Research (CREA), School of Medicine and Health Sciences, Universidad del Rosario, Bogota, Colombia
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Hansen CT, Münster AM, Nielsen L, Pedersen P, Abildgaard N. Clinical and preclinical validation of the serum free light chain assay: identification of the critical difference for optimized clinical use. Eur J Haematol 2012; 89:458-68. [DOI: 10.1111/ejh.12013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2012] [Indexed: 11/27/2022]
Affiliation(s)
| | - Anna-Marie Münster
- Department of Clinical Biochemistry; Hospital of Southwest Denmark; Esbjerg; Denmark
| | - Lars Nielsen
- Department of Clinical Biochemistry; Hospital of Southwest Denmark; Esbjerg; Denmark
| | - Per Pedersen
- Department of Haematology; Hospital of Southwest Denmark; Esbjerg; Denmark
| | - Niels Abildgaard
- Department of Haematology; Odense University Hospital; Odense; Denmark
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Thvilum M, Brandt F, Brix TH, Hegedüs L. A review of the evidence for and against increased mortality in hypothyroidism. Nat Rev Endocrinol 2012; 8:417-24. [PMID: 22392154 DOI: 10.1038/nrendo.2012.29] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The lifetime risk of overt hypothyroidism is around 5%, and this disease is usually preceded by subclinical hypothyroidism, which has an even higher prevalence (estimated to be up to 9%). Hypothyroidism has been linked with cardiac dysfunction, atherosclerosis, hypertension and coagulopathy. Intuitively, this increased morbidity is expected to shorten patients' lifespan, but definitive data are lacking on whether either of these hypothyroid states (particularly overt hypothyroidism) increase mortality. Study findings are inconsistent and, overall, the pooled data do not demonstrate increased mortality in patients with either subclinical or overt hypothyroidism. However, none of the available studies was adequately designed to answer this question. This Review discusses major shortcomings in those studies, such as population dissimilarities, hypothyroid state classification and misclassification, the inclusion of nonthyroidal illness, drug interference from concurrent therapies, serious comorbidities (for example, cardiovascular disease), differences in duration of follow-up and the number of levothyroxine-treated individuals. Taken together, the data exhibit little evidence of systematic bias and no strong scientific proof of increased mortality related to either subclinical or overt hypothyroidism. Future studies, however, should take the above-mentioned shortcomings and potential genetic confounding into consideration.
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Affiliation(s)
- Marianne Thvilum
- Department of Endocrinology and Metabolism, Odense University Hospital, Kløvervænget 6, 5000 Odense C, Denmark
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Deary M, Buckey T, Soldin OP. TSH - Clinical Aspects of its Use in Determining Thyroid Disease in the Elderly. How Does it Impact the Practice of Medicine in Aging? ACTA ACUST UNITED AC 2012; 1. [PMID: 23869289 DOI: 10.4172/2167-1052.1000119] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The last four decades have seen enormous growth in the efficacy of serum thyroid stimulating hormone (thyrotropin, TSH) assay methodology, establishing TSH as the hallmark of thyroid testing. At the center of the considerations is the strong inverse correlation between serum thyrotropin and free thyroxine concentrations. While it is widely accepted that elevated serum TSH concentrations are consistent with thyroid dysfunction, a vast multitude of additional factors must be considered before an accurate clinical diagnosis can be made followed by an appropriate treatment. Epidemiological studies have demonstrated slightly elevated serum TSH concentrations among the elderly population. There is, however, a debate whether these elevated TSH levels reflect an increased prevalence of hypothyroidism among the elderly or a normal aspect of healthy aging. A comprehensive analysis of the many variables associated with this debate and TSH measurement as a diagnostic tool in aging should provide insight into the clinical efforts to diagnose and treat thyroid disease, particularly in the elderly population.
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Affiliation(s)
- Mackenzie Deary
- Georgetown University Medical Center, 3800 Reservoir Road NW, Washington DC 20057, USA
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Ozdemir I, Calka O, Karadag A, Akdeniz N, Ozturk M. Thyroid autoimmunity associated with recurrent aphthous stomatitis. J Eur Acad Dermatol Venereol 2011; 26:226-30. [DOI: 10.1111/j.1468-3083.2011.04040.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Schalin-Jäntti C, Tanner P, Välimäki MJ, Hämäläinen E. Serum TSH reference interval in healthy Finnish adults using the Abbott Architect 2000i Analyzer. Scand J Clin Lab Invest 2011; 71:344-9. [DOI: 10.3109/00365513.2011.568630] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Arzideh F, Wosniok W, Haeckel R. Indirect reference intervals of plasma and serum thyrotropin (TSH) concentrations from intra-laboratory data bases from several German and Italian medical centres. Clin Chem Lab Med 2011; 49:659-64. [PMID: 21342020 DOI: 10.1515/cclm.2011.114] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND The dogma of establishing intra-laboratory reference limits (RLs) and their periodic review cannot be fulfilled by most laboratories due to the expenses involved. Thus, most laboratories adopt external sources for their RLs, often neglecting the problems of transferability. This is particularly problematic for analytes with a large diversity of existing RLs, as for example thyrotropin (TSH). Several attempts were taken to derive RLs from the large data pools stored in modern laboratory information systems. These attempts were further developed to a more sophisticated indirect procedure. The new approach can be considered a combined concept because it pre-excludes some subjects by direct criteria a-posterior. In the current study, the applicability of the new concept for modern protein bindings assays was examined for estimating RLs of serum and plasma TSH with data sets from several German and Italian laboratories. METHODS A smoothed kernel density function was estimated for the distribution of the total mixed data of the sample group (combined data of non-diseased and diseased subjects). It was assumed that the "central" part of the distribution of all data represents the non-diseased ("healthy") population. The central part was defined by truncation points using an optimisation method, and was used to estimate a Gaussian distribution of the values of presumably non-diseased subjects after Box-Cox transformation of the empirical data. This distribution was now considered as the distribution of the non-diseased subgroup. The percentiles of this parametrical distribution were calculated to obtain RLs. RESULTS RLs determined by the indirect combined decomposition technique led to similar RLs as found by several recent study reports using a direct method according to international recommendations. Furthermore, the RLs obtained from 13 laboratories in two different European regions reflected the well-known differences of various analytical procedures. Stratification for gender and age was necessary in contrast to earlier reports. With increasing age, an increase of the upper RL and the reference range was observed. Hospitalisation also affected the RLs. Common RLs appeared acceptable only within the same analytical systems. Some laboratories used RLs which were not appropriate for the population served. CONCLUSIONS The proposed strategy of combining exclusion criteria with a resolution technique led to retrospective RLs from intra-laboratory data pools for TSH which were comparable with directly determined RLs. Differences between laboratories were due primarily to the well-known bias of the different analytical procedures and to the status of the population.
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Affiliation(s)
- Farhad Arzideh
- Institut für Statistik, Universität Bremen, Bremen, Germany
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Roos A, Links TP, de Jong-van den Berg LTW, Gans ROB, Wolffenbuttel BHR, Bakker SJL. Thyroid peroxidase antibodies, levels of thyroid stimulating hormone and development of hypothyroidism in euthyroid subjects. Eur J Intern Med 2010; 21:555-9. [PMID: 21111944 DOI: 10.1016/j.ejim.2010.09.001] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/16/2010] [Revised: 08/21/2010] [Accepted: 09/03/2010] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Thyroid peroxidase antibodies (TPOAbs) have been found to be related to the levels of thyroid stimulating hormone (TSH) and to predict future development of thyroid failure in selected populations. We investigated these relations in a euthyroid general population. DESIGN Cross-sectional investigation of the relationship of TPOAbs and levels of TSH in euthyroid subjects. Prospective investigation of the association of TPOAbs and TSH with development of hypothyroidism. Incident hypothyroidism was defined as initiation of l-thyroxine in the absence of thyreostatic medication. SUBJECTS The study was performed in a random sample of 2703 participants of the PREVEND study. A total of 309 subjects were excluded from analyses, mainly because of TSH outside the reference range (0.35-4.94 mIU/l; n=115). RESULTS Mean (SD) baseline age was 47.7 (12.5) years, with 50.8% females. Prevalence of positive TPOAbs (≥ 12 kU/l) was 8.4%. TSH concentrations were increased in subjects with TPOAbs (P<0.001). During a median follow-up of 9.1 years, 15 (0.6%) subjects developed hypothyroidism (3.5% in TPOAbs positive vs. 0.4% in TPOAbs negative subjects; P<0.001). Female sex (P=0.02), and TSH (P<0.001) were also significantly associated with incident hypothyroidism. In multivariate analysis, TSH and TPOAbs remained independent predictors (both P<0.001). CONCLUSIONS We confirmed the positive relationship of the presence of TPOAbs with levels of TSH and showed that TPOAbs and TSH predict future development of hypothyroidism. These results are consistent with the presence of TPOAbs necessitating a compensatory increase in levels of TSH for maintenance of euthyroidism, even in the euthyroid range.
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Affiliation(s)
- Annemieke Roos
- Department of Endocrinology, Groningen University Institute for Drug Exploration, University Medical Center Groningen and University of Groningen, The Netherlands
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Brix TH, Hansen PS, Kyvik KO, Hegedüs L. The pituitary-thyroid axis set point in women is uninfluenced by X chromosome inactivation pattern? A twin study. Clin Endocrinol (Oxf) 2010; 73:666-70. [PMID: 20718768 DOI: 10.1111/j.1365-2265.2010.03848.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
OBJECTIVE The pituitary-thyroid axis (PTA) set point is determined by a combination of genetic and environmental factors. However, despite considerable efforts to characterize the background, the causative genes as well as environmental factors are not well established. Theoretically, as shown for autoimmune thyroid disease, the pattern of X chromosome inactivation (XCI) could offer a novel explanation for the observed variability of the PTA set point in women. DESIGN AND PATIENTS To examine the impact of XCI pattern on the PTA set point, we studied whether within-cohort (n = 318 subjects) and within-twin pair (n = 159 pairs) differences in XCI are correlated with serum concentrations of thyrotropin (TSH), free triiodothyronine (FT3) and free thyroxine (FT4). METHODS X chromosome inactivation was determined by PCR analysis of a polymorphic CAG repeat in the first exon of the androgen receptor gene. Thyroid variables were measured using a solid-phase time-resolved fluoroimmunometric assay. Zygosity was established by DNA fingerprinting. RESULTS In the overall study population (within cohort), no significant correlations were found between TSH [regression coefficient (β) = -0·28 (95% confidence intervals, -0·66 to 0·11), P = 0·158], FT3 [β = -0·25 (-0·85 to 0·34), P = 0·403], FT4 [β = 0·08 (-0·91 to 1·07), P = 0·876] and XCI pattern. Essentially similar results were found in the within-pair analysis. Controlling for confounders such as age, body mass index, smoking and zygosity did not change the findings. CONCLUSIONS In a sample of female twins, we found no evidence of a relationship between XCI pattern and PTA set point.
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Affiliation(s)
- Thomas H Brix
- Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark.
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Brix TH, Hegedüs L, Gardas A, Banga JP, Nielsen CH. Monozygotic twin pairs discordant for Hashimoto's thyroiditis share a high proportion of thyroid peroxidase autoantibodies to the immunodominant region A. Further evidence for genetic transmission of epitopic “fingerprints”. Autoimmunity 2010; 44:188-94. [DOI: 10.3109/08916934.2010.518575] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Rosario PW, Xavier ACM, Calsolari MR. TSH reference values for adult Brazilian population. ACTA ACUST UNITED AC 2010; 54:603-6. [DOI: 10.1590/s0004-27302010000700003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Accepted: 08/21/2010] [Indexed: 11/22/2022]
Abstract
OBJECTIVE: To establish limits of normal serum TSH for the adult (18 to 60 years) Brazilian population according to recommendations of the National Academy of Clinical Biochemistry. SUBJECTS AND METHODS: Healthy volunteers were evaluated and those fulfilling the following clinical criteria were selected: absence of known thyroid disease; no use of any interfering medications; no history of head and neck external radiotherapy, type 1 diabetes or autoimmune disease; no family history of thyroid disease, and absence of goiter or palpable nodules. Subjects with anti-thyroperoxidase antibodies and/or altered free T4 were excluded. The sample consisted of 960 subjects (480 males and 480 females). RESULTS: TSH values corresponding to the 2.5th and 97.5th percentiles of the sample were 0.43 and 3.24 mIU/L, respectively. TSH values > 2.5 mIU/L were observed in 9.15% of the volunteers and levels > 3 mIU/L in 3.11%. CONCLUSION: The present study suggests an upper limit of normal TSH of approximately 3.5 mIU/L.
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Walsh JP, Bremner AP, Feddema P, Leedman PJ, Brown SJ, O'Leary P. Thyrotropin and thyroid antibodies as predictors of hypothyroidism: a 13-year, longitudinal study of a community-based cohort using current immunoassay techniques. J Clin Endocrinol Metab 2010; 95:1095-104. [PMID: 20097710 DOI: 10.1210/jc.2009-1977] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Longitudinal studies of risk factors for hypothyroidism are required to inform debate regarding the TSH reference range. There are limited longitudinal data on the predictive value of thyroid antibodies measured by automated immunoassay (as opposed to semiquantitative methods). METHODS We measured TSH, free T(4), thyroid peroxidase antibodies (TPOAbs), and thyroglobulin antibodies (TgAbs) using the Immulite platform on sera from 1184 participants in the 1981 and 1994 Busselton Health Surveys. Outcome measures at follow-up were hypothyroidism, defined as TSH greater than 4.0 mU/liter or on thyroxine treatment; and overt hypothyroidism, defined as TSH above 10.0 mU/liter or on thyroxine treatment. Receiver-operator characteristic analysis was used to determine optimal cutoffs for baseline TSH, TPOAbs, and TgAbs as predictors of hypothyroidism. RESULTS At 13 yr follow-up, 110 subjects (84 women) had hypothyroidism, of whom 42 (38 women) had overt hypothyroidism. Optimal cutoffs for predicting hypothyroidism were baseline TSH above 2.5 mU/liter, TPOAbs above 29 kIU/liter, and TgAbs above 22 kIU/liter, compared with reference range upper limits of 4.0 mU/liter, 35 kIU/liter, and 55 kIU/liter, respectively. In women with positive thyroid antibodies (TPOAbs or TgAbs), the prevalence of hypothyroidism at follow-up (with 95% confidence intervals) was 12.0% (3.0-21.0%) when baseline TSH was 2.5 mU/liter or less, 55.2% (37.1-73.3%) for TSH between 2.5 and 4.0 mU/liter, and 85.7% (74.1-97.3%) for TSH above 4.0 mU/liter. CONCLUSIONS The use of TSH cutoffs of 2.5 and 4.0 mU/liter, combined with thyroid antibodies, provides a clinically useful estimate of the long-term risk of hypothyroidism.
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Affiliation(s)
- John P Walsh
- Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, Western Australia 6009.
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Brix TH, Hansen PS, Bennedbak FN, Bonnema SJ, Kyvik KO, Ørstavik KH, Hegedüs L. X Chromosome inactivation pattern is not associated with interindividual variations in thyroid volume: a study of euthyroid Danish female twins. Twin Res Hum Genet 2010; 12:502-6. [PMID: 19803777 DOI: 10.1375/twin.12.5.502] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Ahigher frequency of skewed X chromosome inactivation (XCI) is found in patients with autoimmune thyroid disease (AITD) than in controls. Although goitre is often present in AITD, a recent study failed to show an association between XCI and clinically overt nontoxic goitre. However, the etiology of overt goitre is complex, and the mechanisms influencing thyroid volume may involve fewer factors than the mechanisms underlying overt goitre. In order to examine the impact of XCI on thyroid volume in euthyroid females, we studied whether within cohort (n = 138) and within twin pair (n = 69) differences in XCI are correlated with differences in thyroid volume. XCI was determined by PCR analysis of a polymorphic CAG repeat in the first exon of the androgen receptor gene. Thyroid volume was determined by ultrasound. Neither in the within cohort nor in the within twin pair analysis could we demonstrate a statistically significant association between XCI and thyroid volume: Regression coefficient (beta) = 0.023 (95% confidence interval, -0.062-0.108), p = 0.592 and beta = 0.038 (-0.080-0.156), p = 0.521, respectively. Controlling for potential confounders such as zygosity, age, TSH, smoking habits and use of oral contraceptives did not change the findings. In conclusion, in a sample of euthyroid Danish female twins, we found no evidence of a relationship between XCI pattern and thyroid volume.
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Affiliation(s)
- Thomas Heiberg Brix
- Department of Endocrinology and Metabolism, Odense University Hospital, Denmark.
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Brix TH, Hansen PS, Kyvik KO, Hegedüs L. Aggregation of thyroid autoantibodies in twins from opposite-sex pairs suggests that microchimerism may play a role in the early stages of thyroid autoimmunity. J Clin Endocrinol Metab 2009; 94:4439-43. [PMID: 19808849 DOI: 10.1210/jc.2009-0813] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
CONTEXT Microchimerism is the presence of small populations of cells from one individual in another genetically distinct individual. This phenomenon can arise from pregnancy, blood transfusion, or bidirectional cell trafficking between twins in utero. Microchimerism has recently been proposed to play a role in the pathogenesis of thyroid autoimmunity. In that case, twins from opposite-sex pairs (OS) should have an increased risk of thyroid autoantibodies (TA). AIM The aim of the study was to compare the frequency of TA in twin individuals from OS and monozygotic (MZ) twin pairs. DESIGN This was a case-control study of 240 individuals (120 females and 120 males) from OS twin pairs (cases) and 568 control individuals from MZ pairs (284 females and 284 males). METHODS Antibodies toward thyroid peroxidase (TPOAb), thyroglobulin (TgAb), and the TSH receptor (TSHRAb) were measured and considered positive if greater than 60 U/ml, greater than 60 U/ml, and greater than 1.0 U/liter, respectively. RESULTS The frequency of TPOAb, TgAb, and TSHRAb among female cases was 15.0, 5.0, and 4.2%, respectively, which was higher than the corresponding prevalences in the female control population: 7.4% (P = 0.018), 1.1% (P = 0.023), and 0.7% (P = 0.026), respectively. However, when corrected for the number of phenotypes studied (TPOAb, TgAb, TSHRAb, and any thyroid antibody), the association remained significant only in the combined group, P(corrected) = 0.012. Essentially similar results were obtained in males. CONCLUSION Both female and male twins from OS pairs, as opposed to MZ pairs, have an increased frequency of TA, indicating a potential role of microchimerism in developing TA.
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Affiliation(s)
- Thomas Heiberg Brix
- Department of Endocrinology and Metabolism, Odense University Hospital, 5000 Odense C, Denmark. thomas.brix@ouh
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Malati T. Whether western normative laboratory values used for clinical diagnosis are applicable to Indian population? An overview on reference interval. Indian J Clin Biochem 2009; 24:111-22. [PMID: 23105819 PMCID: PMC3453230 DOI: 10.1007/s12291-009-0022-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Reference Intervals denote normative values related to laboratory parameters/analytes used by diagnostic centers for clinical diagnosis. International guidelines recommend that every country must establish reference intervals for healthy individuals belonging to a group of homogeneous population. Considering enormous racial and ethnic diversity of Indian population, it is mandatory to establish reference intervals specific to Indian population. The overview on reference interval describes why the national organizations in India need to initiate nationwide efforts to establish its own laboratory standards for apparently healthy reference individuals belonging to our polygenetic, polyethnic, polyracial, multilinguistic and multicultural predominantly rural and appreciable urban Indian population with varied dietary habits.
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Affiliation(s)
- T. Malati
- Department of Biochemistry, Nizam’s Institute of Medical Sciences, Punjagutta, Hyderabad, 500 082 Andhra Pradesh
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Brix TH, Hansen PS, Knudsen GPS, Kringen MK, Kyvik KO, Orstavik KH, Hegedüs L. No link between X chromosome inactivation pattern and simple goiter in females: evidence from a twin study. Thyroid 2009; 19:165-9. [PMID: 19191747 DOI: 10.1089/thy.2008.0380] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Simple goiter (SG) comprises diffuse (DG) and nodular (NG) benign nonautoimmune nontoxic goiter. In nonendemic goiter areas, the ratio of females to males may exceed 5:1, indicating that gender and/or sex hormones may play a role in the etiology of SG in these areas. Theoretically, as shown for autoimmune thyroid disease, X chromosome inactivation (XCI) and resultant tissue chimerism could offer a novel explanation for the female preponderance of SG. To examine whether skewed XCI is associated with SG, we first compared XCI in 71 twin individuals with SG with that in 142 unrelated healthy control twin individuals, and then performed a within-pair comparison of XCI in 48 twin pairs discordant for SG. METHODS DNA was extracted from peripheral blood cells. XCI analysis was performed by predigestion of DNA using the methylation-sensitive enzyme Hpall, followed by polymerase chain reaction of the polymorphic CAG repeat of the androgen receptor gene. A polymerase chain reaction product is obtained from the inactive X chromosome only. The XCI pattern was classified as skewed when 80% or more of the cells preferentially inactivated the same X chromosome. Twin zygosity was established by DNA fingerprinting. RESULTS The frequency of skewed XCI in female twins with SG, DG, and NG was 11% (8/71), 13% (6/46), and 8% (2/25), respectively, which was not significantly different from the prevalences in the corresponding control populations, 14% (20/142, p = 0.56), 14% (13/92, p = 1.00), and 14% (7/50, p = 0.71), respectively. Essentially, similar results were obtained when comparing the prevalence of skewed XCI in twin pairs discordant for SG (48 pairs), DG (30 pairs), and NG (18 pairs). CONCLUSION In a sample of Danish female twins, we did not find evidence for involvement of skewed XCI in the etiology or the female preponderance of SG.
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Affiliation(s)
- Thomas Heiberg Brix
- Department of Endocrinology and Metabolism, Odense University Hospital, Odense, Denmark.
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Waise A, Price HC. The upper limit of the reference range for thyroid-stimulating hormone should not be confused with a cut-off to define subclinical hypothyroidism. Ann Clin Biochem 2009; 46:93-8. [PMID: 19164339 DOI: 10.1258/acb.2008.008113] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The upper limit of the reference range for serum thyroid-stimulating hormone (TSH) is used to assist in identifying individuals with hypothyroidism. Improvements in TSH assays have led to better definition of the lower limit of the reference range, but the upper limit of the range for a healthy population is currently a topic of some debate. Population studies have improved our understanding of the clinical implications of elevated serum TSH concentrations in terms of future progression to hypothyroidism, but have not yet fully elucidated the correlation of modestly elevated TSH levels with long-term morbidity. This paper will review the current debate including the arguments for and against reducing the upper limit of the TSH range, whether such a level should be based on evidence from epidemiological studies, and the implications of categorizing large numbers of people with subclinical hypothyroidism. The impact of using different methodologies for the measurement of TSH and the inherent variability of results on reference ranges is also discussed. We argue that the reference range for TSH should be assay-specific and be determined by standard techniques in normal populations as recommended by the National Academy of Clinical Biochemistry. In contrast, we suggest that a decision level be determined separately from epidemiological studies to identify a population with subclinical hypothyroidism. Serial monitoring of TSH in this population deserves further study as a means of identifying those at risk of progressing to frank hypothyroidism and meriting treatment.
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Affiliation(s)
- Ahmed Waise
- Laboratory Medicine, York Hospital, York, UK.
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Tozzoli R, Giavarina D, Villalta D, Soffiati G, Bizzaro N. Definition of reference limits for autoantibodies to thyroid peroxidase and thyroglobulin in a large population of outpatients using an indirect method based on current data. Arch Pathol Lab Med 2009; 132:1924-8. [PMID: 19061292 DOI: 10.5858/132.12.1924] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/08/2008] [Indexed: 11/06/2022]
Abstract
CONTEXT The reference limits for thyroid antibodies are generally made by measuring thyroid peroxidase and thyroglobulin antibody values in a group of healthy subjects (direct method), as proposed by the National Academy of Clinical Biochemistry. OBJECTIVE To define the upper reference limits of thyroid peroxidase and thyroglobulin, by using an indirect method to analyze data from a large number of outpatients that were stored in the information system of a general hospital laboratory. DESIGN Thyroid peroxidase and thyroglobulin values from 21 492 patients, who had undergone antithyroid antibody measurements, were retrieved from the laboratory information system; the upper reference limits (in the top 97.5 percentile) were calculated using the indirect Kairisto method, after exclusion of outliers. RESULTS The mean upper reference limits for females and males were 15 kIU/L and 9 kIU/L for thyroid peroxidase, and 21 kIU/L and 19 kIU/L for thyroglobulin, respectively. The upper limits showed minimal or no differences in the different age classes in either females or males. CONCLUSIONS Using a vast population of patients, we demonstrated that the upper limits for thyroid antibodies are much lower than the values obtained with classic, direct methods and that they do not vary in relation to age and sex.
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Affiliation(s)
- Renato Tozzoli
- Laboratory of Clinical Pathology, Ospedale Civile, Latisana, Italy
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Estaquio C, Valeix P, Leenhardt L, Modigliani E, Boutron-Ruault MC, Chérié-Challine L, Legrand M, Hercberg S, Castetbon K. Serum thyrotropin and free thyroxine reference ranges as defined in a disease-free sample of French middle-aged adults. Clin Chem Lab Med 2009; 47:1497-505. [DOI: 10.1515/cclm.2009.334] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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