TSH Measurements Research Articles

Hot Thyroid Nodule Revealing a Papillary Microcarcinoma: A Case Report

Introduction: Autonomously hyperfunctioning thyroid nodules, also known as "hot nodules", are defined by increased uptake of radiotracers compared to the surrounding thyroid parenchyma on scintigraphy. It has been believed that hot nodules have a low rate of malignancy, while an increasing number of thyroid carcinoma cases are being diagnosed in patients with hyperthyroidism. Case Presentation: A. J, a 50-year-old patient. She presented with signs of hyperthyroidism. Laboratory tests showed peripheral hyperthyroidism with an inhibited TSH of 0.03 μIU/ml and T4L of 37 pmol/L. The scintigraphy revealed a focus of hyper fixation almost completely affecting the right lobe which corresponded to a hot nodule most likely pre-extincted in the remaining parenchyma. The patient was initiated on synthetic antithyroid medication and, after achieving euthyroidism, she was referred to surgery. Right loboishmectomy was performed. The histological study revealed a 0.5 cm intralobular non-encapsulated microcarcinoma papillary on a background of thyroid dystrophy. Discussion: The initial evaluation of a thyroid nodule begins is the measurement of serum TSH and the performance of a thyroid ultrasound, followed by a thyroid radionuclide scan if the TSH is subnormal. Malignant nodules are usually non-functioning. The prevalence of malignancy associated with a hot nodule range between 1-10.3%. In many cases, thyroid cancer is not known preoperatively but is found incidentally during the postoperative histological examination of the thyroid. Most of these malignancies were of papillary carcinoma and less often follicular or Hurthle histological types, and they are small in size, and the majority are microcarcinomas. Conclusion: Further evaluation and characterization of the association between a hot thyroid nodule and malignancy are needed. In the case of our patient, the discovery of papillary carcinoma was incidental and was made during the postoperative histological examination .......

A PROSPECTIVE CLINICAL STUDY OF THYROID MALIGNANCIES AND THE ROLE OF SERUM TSH IN PREDICTING MALIGNANCY

Introduction: Serum TSH is an independent predictor of malignancy in thyroid nodules according to the recent publications. Thyroid malignancies could be screened by using this biochemical marker (TSH) as a preliminary step. In this study, we looked into the usefulness of TSH in predicting cancer as well as the typical clinical presentation of thyroid cancers. Aims And Objectives: To assess the value of serum TSH measurement as a biochemical predictor of malignancy in suspicious thyroid nodules and to study the clinical manifestations and management of different thyroid malignancies. Place of Study: NRI Medical College Materials And Methods: and General Hospital, chinnakakani. Study population: All patients presented to General Surgery Department of NRI medical college and hospital, chinnakakani with clinically suspicious thyroid swellings of malignancy during the study period. Duration of Study: This was done over period Of one year from August 2021 to August 2022. It has a follow up of 6 months. Most of the Results: patients were females.40 years is the mean age of malignancy.mean age in male is 59 years and the mean age in females is 38 years. It commonly manifested as a rapidly growing swelling in the thyroid with shorter duration or development of secondary symptoms in a long standing goiter. Most of the patients are presented with STN. Malignancy occurred more frequently in SNT (36%) than MNG (19%).%. Mean preoperative TSH values of benign illness is less compared to those with malignancy. Higher TSH readings were associated with an increased risk of cancer. Higher TSH levels are Conclusion: denitely used as a predictor. The FNAC can be reexamined in these circumstances where the TSH result is high to correlated with malignancy. In cases with clinically suspected malignant thyroid swelling with a benign FNAC report, TSH values may be conrm the diagnosis

Impacto de la tirotrofina preconcepcional en los resultados obstétricos en población fértil

IntroductionThere is evidence that subclinical hypothyroidism is associated with infertility, miscarriage and obstetric complications. However, there is controversy regarding the optimal TSH value in women seeking pregnancy.Current guidelines recommend that hypothyroid women with levothyroxine replacement who are planning pregnancy should optimise the dose of levothyroxine to achieve thyrotrophin (TSH) levels < 2.5 mU/L, since these requirements increase in pregnancy, thus reducing the risk of TSH elevation during the first trimester.In women with infertility, who undergo highly complex treatments and have positive thyroid autoimmunity, values of TSH < 2.5 mU/L prior to fertility treatment are suggested.Although this is a different population, these «optimal» TSH levels were also extended to euthyroid women without evidence of infertility, who are seeking pregnancy. ObjectivesDetermine whether preconception TSH levels between 2.5 and 4.64 mIU/L are associated with adverse obstetric outcomes in euthyroid women. Materials and methodsRetrospective cohort study. We evaluated 3,265 medical records of pregnant women aged 18 to 40 years, euthyroid (TSH 0.5-4.64 mU/ml), with TSH measurement at least one year before gestation. 1,779 met inclusion criteria. The population was divided according to categories: TSH 0.5- 2.4 mU/L (optimal) and TSH 2.5-4.6 mU/L (suboptimal). Information on maternal and fetal obstetric outcomes was collected from each group. ResultsWe found no statistical difference in the occurrence of adverse obstetric events between the two groups. There was also no difference when adjusting for thyroid autoimmunity, age, body mass index, previous diabetes and previous arterial hypertension. ConclusionOur results suggest that the reference range of TSH used in the general population could be used in women seeking pregnancy, even in the presence of thyroid autoimmunity. Treatment with levothyroxine should be considered only in patients with special situations.

Thyroid Dysfunction and Cardiovascular Events in Patients With Dysglycemia

ObjectivesSubclinical thyroid disease is the most common form of thyroid dysfunction and may be associated with adverse cardiovascular outcomes in people at high risk for cardiovascular events. Our objective in this study was to assess the association of thyroid function and thyroid hormone replacement with cardiovascular outcomes in high-risk individuals with dysglycemia and additional cardiovascular risk factors. MethodsThe relationship between baseline thyrotropin (TSH) level and incidence of the composite outcome of nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death; an expanded composite of this outcome plus revascularization or hospitalization for heart failure; and mortality was assessed in 8,401 ORIGIN trial participants with a baseline measurement of TSH. The hazard of each outcome according to either baseline levothyroxine use or TSH-defined hyperthyroidism, euthyroidism, subclinical hypothyroidism, and overt hypothyroidism was estimated before and after adjustment for baseline demographic and clinical characteristics and treatment allocation. ResultsOf all participants, 91.5% were euthyroid, 0.8% were hyperthyroid, 5.5% had subclinical hypothyroidism, and 2.2% had overt hypothyroidism. Subclinical hypothyroidism predicted both the expanded cardiovascular outcome (hazard ratio [HR]=1.24, 95% confidence interval [CI] 1.06 to 1.46) and mortality (HR=1.37, 95% CI 1.12 to 1.67), whereas levothyroxine use predicted fewer deaths (HR=0.72, 95% CI 0.56 to 0.94). ConclusionSubclinical hypothyroidism predicts future cardiovascular events and mortality in people with dysglycemia and other cardiovascular risk factors.

Iodinated Contrast Administration and Risks of Thyroid Dysfunction: A Retrospective Cohort Analysis of the U.S. Veterans Health Administration System.

Background: Iodine-induced thyroid dysfunction is a potential risk among susceptible individuals. Iodinated contrast media is a common source of an acute iodine load used in the health care setting and is frequently required for diagnostic computed tomography scans, coronary angiograms, and other radiologic studies. However, the epidemiologic risks of iodine-thyroid dysfunction have not been fully established in the United States. Methods: This population-based retrospective cohort study used the U.S. Veterans Health Administration database between 1998 and 2021 and included adults aged ≥18 years with a serum thyrotropin (TSH) measurement. Multivariable logistic regression was used to ascertain the risk of incident thyroid dysfunction (defined by repeated measurements of serum thyroid function) following iodine exposure, adjusting for age, sex, race/ethnicity, baseline serum TSH concentration, and duration between baseline and follow-up TSH concentration. Results: The cohort was composed of N = 4,253,119 veterans (mean ± SD = 63.5 ± 14.3 years; 92.9% men; 65.6% non-Hispanic Whites) with 8,729,155 corresponding pairs of serum TSH measurements, from which there were 499,897 TSH pairs with intervening iodine exposure. Thyroid dysfunction occurred in 4.8% of those pairs who had received iodine contrast and 3.6% of those without iodine exposure. Iodinated exposure was associated with an increased risk of thyroid dysfunction (odds ratio [OR] = 1.39, 95% confidence intervals [CI] = 1.37-1.41, p < 0.001) and consistent for all types of serum thyroid dysfunction (overt or subclinical hypo-/hyperthyroidism). Men were at higher risk for the development of thyroid dysfunction than women (men: OR = 1.42, 95% CI = 1.40-1.44; women: OR = 1.16, 95% CI = 1.11-1.21; p-for-interaction <0.001). Conclusions: In this largest analysis of U.S. adults to date, iodine exposure was associated with only clinically small absolute increased risks of thyroid dysfunction, particularly in men. These findings suggest that screening of thyroid function following iodinated contrast administration should be targeted to high-risk individuals.

Developmental exposure to thyroid disruptors: misprogramming of the brain's stem cells in later life?

Developmental exposure to thyroid disruptors: misprogramming of the brain's stem cells in later life?

Thyroid Hormone Levels in Preterm Neonates with Birth Weight Less than 2500 g, Treated with Phenobarbital.

Indicatively, phenobarbital can impair thyroid function in adults and children. The present research aims to evaluate the thyroid hormone levels in preterm neonates who had received phenobarbital treatment. This study was conducted on preterm neonates who weighed less or equal to 2500 g when phenobarbital was prescribed for treatment in the first 15 days of life. TSH and total T4 measurements were performed before and three months after initiation of phenobarbital. In this study, the sum of preterm neonates stood at 94, of which 53 were girls, with a mean birth weight of 2004.41 ± 315.41g. Weight of 8.5% were under 1500 g. The mean gestational age was estimated at 33.64 ± 2.01 weeks. Mean T4 levels were 12.24 ± 1.96 and 12.07 ± 1.95 (p=0.334), and mean TSH levels were 5.34 ± 2.14 and5.15 ± 2.15 (p=0.376) before and after prescribing phenobarbital, respectively. The same results were compared based on sex, gestational age, birth weight, and height for T4 and TSH and T4 based on head circumference. The only significant difference was TSH in preterm infants with head circumference <32 cm before and after prescribing phenobarbital (p=0.030). In preterm newborns that had less than 2500 g birth weight, phenobarbital did not significantly alter the serum thyroid hormone levels.

Tumor PD-L1 expression and molecular profiling are not associated with immune checkpoint inhibitor-induced thyroid dysfunction in advanced NSCLC patients.

Background: Immune-checkpoint inhibitors (ICIs) have revolutionized the treatment of advanced non-small cell lung cancer (NSCLC), however are frequently associated with thyroid immune-related adverse events (IRAEs). We investigated the association between patient characteristics, tumor PD-L1 expression and molecular profile with the development of thyroid IRAEs in NSCLC patients. Methods: Single center, retrospective study including 107 NSCLC patients treated with PD-1/PD-L1 inhibitors from April 2016 to July 2020. All patients were euthyroid at baseline with at least two TSH measurements post-treatment initiation. The primary outcome was the difference in tumor PD-L1 expression in patients who developed any thyroid IRAEs versus those who remained euthyroid. Additional outcomes included development of overt thyroid dysfunction, the association of specific molecular alterations with thyroid IRAEs, and onset of thyroid IRAEs as a function of tumor PD-L1 expression. Results: Overall, 37 (34.6%) patients developed any thyroid dysfunction and 18 (16.8%) developed overt thyroid dysfunction. Tumor PD-L1 staining intensity was not associated with thyroid IRAEs. TP53 mutation was less likely to be associated with any thyroid dysfunction (p < 0.05) and no association was found between EGFR, ROS, ALK or KRAS mutations. There was no association between PD-L1 expression and time to develop thyroid IRAEs. Conclusion: PD-L1 expression is not associated with the development of thyroid dysfunction in advanced NSCLC patients treated with ICIs, suggesting that thyroid IRAEs are unrelated to tumor PD-L1 expression.

Thyrotropin Levels in Patients with Coronavirus Disease 2019: Assessment during Hospitalization and in the Medium Term after Discharge.

The objectives of this study were (1) to compare TSH levels between inpatients with critical versus non-critical coronavirus disease 19 (COVID-19), and (2) to describe the status of TSH levels three months after hospitalization. We collected data on adult patients hospitalized with COVID-19 at Amiens University Hospital. We compared TSH levels between inpatients with critical (intensive care unit admission and/or death) versus non-critical COVID-19. Thereafter, survivors were invited to return for a three-month post-discharge visit where thyroid function tests were performed, regardless of the availability of TSH measurement during hospitalization. Among 448 inpatients with COVID-19, TSH assay data during hospitalization were available for 139 patients without prior thyroid disease. Patients with critical and non-critical forms of COVID-19 did not differ significantly with regard to the median (interquartile range) TSH level (0.96 (0.68-1.71) vs. 1.27 mIU/L (0.75-1.79), p = 0.40). Abnormal TSH level was encountered in 17 patients (12.2%); most of them had subclinical thyroid disease. TSH assay data at the three-month post-discharge visit were available for 151 patients without prior thyroid disease. Only seven of them (4.6%) had abnormal TSH levels. Median TSH level at the post-discharge visit was significantly higher than median TSH level during hospitalization. Our findings suggest that COVID-19 is associated with a transient suppression of TSH in a minority of patients regardless of the clinical form. The higher TSH levels three months after COVID-19 might suggest recovery from non-thyroidal illness syndrome.

Cut-offs for thyroid peroxidase and thyroglobulin antibodies in early pregnancy.

Thyroid disease in women of reproductive age is mainly of autoimmune origin, and thyroid peroxidase antibodies (TPO-Ab) as well as thyroglobulin antibodies (Tg-Ab) are key markers. Adding to this, much focus in pregnancy is on euthyroid women who are thyroid antibody positive. Evidence to substantiate the cut-offs for the definition of thyroid autoantibody positivity in early pregnant women is warranted. Stored serum samples from 14,030 Danish pregnant women were used for the measurement of TPO-Ab, Tg-Ab, TSH, and free thyroxine (ADVIA Centaur XPT, Siemens Healthineers). Among all women, a reference cohort of 10,905 individuals was identified for the establishment of antibody cut-offs. Percentile cut-offs for TPO-Ab and Tg-Ab were determined using regression on order statistics (the reference cohort). The established cut-offs were then applied (the full cohort), and frequencies of early pregnancy as well as later diagnosis of hypothyroidism were evaluated. The highest established cut-offs (95th, 97.5th, and 99th percentiles) were 59, 68, and 81 U/mL for TPO-Ab and 33, 41, and 52 U/mL for Tg-Ab. When the cut-offs were applied in the full cohort, 11.0, 10.2, and 9.7% were TPO-Ab positive, whereas 13.3, 12.3, and 11.2% were Tg-Ab positive. Antibody-positive women (TPO-Ab and/or Tg-Ab) had higher median TSH and were more likely to have hypothyroidism in early pregnancy and to be diagnosed with hypothyroidism during follow-up. This large study established and evaluated pregnancy-specific cut-offs for TPO-Ab and Tg-Ab. The findings are important regarding the classification of exposure in pregnancy and assessment of thyroid autoimmunity per se.

Abnormal TSH Prior to Surgery in Children with Graves' Disease Predicts Abnormal TSH Following Thyroidectomy.

To identify variables that are associated with poor compliance to thyroid hormone replacement therapy in children after total thyroidectomy. A retrospective cohort study of children who underwent total thyroidectomy by high-volume pediatric otolaryngologists between 1/2014 and 9/2021. Postoperative poor compliance was characterized by at least three separate measurements of high TSH levels not associated with radioactive iodine treatment. There were 100 patients, ages 3-20 years old who met inclusion criteria; 44 patients underwent thyroidectomy for cancer diagnosis, and 56 for Graves' disease. The mean follow-up time was 36.5 months (range 3.0-95.6 months). Overall, 42 patients (42%) were found to have at least three measurements of high TSH during follow-up, and 29 patients (29%) were diagnosed with clinical hypothyroidism. Sex, race, income, insurance type, and benign versus malignant etiology for thyroidectomy were not associated with adherence to therapy. Multivariate regression analysis identified patients with Graves' disease and hyperthyroidism at the time of surgery and Hispanic ethnicity to be associated with postoperative clinical hypothyroidism (OR 9.38, 95% CI 2.16-49.2, p=0.004 and OR 6.15, 95% CI 1.21-36.0, p=0.033, respectively). Preoperative hyperthyroidism in patients with Graves' disease and Hispanic ethnicity were predictors of postoperative TSH abnormalities. Preoperative counseling for patients and their families on the implications of total thyroidectomy and the need for life-long medications postoperatively is necessary. Efforts should be made to evaluate and improve adherence to therapy pre-and postoperatively in patients with Graves' disease. 4 Laryngoscope, 133:2402-2406, 2023.

How Should I Take My Levothyroxine?

How Should I Take My Levothyroxine?

LBSAT247 Factors Guiding Successful Treatment Discontinuation In Levothyroxine Replacement Therapy Overuse: Short And Long-term Observation Data Of 802 Subjects.

Abstract Background Levothyroxine (LT4-Rx) is one of the most commonly prescribed drugs worldwide and the vast majority of patients receive long-term treatment. However, in a recent study of LT4-Rx withdrawal in 291 subjects, it was found that 60% of those remained biochemically euthyroid two months after LT4-Rx discontinuation1. Aim of the study A prospective clinical cohort follow-up study was carried out to address this issue. We registered all patients presented in our clinical practice who were not on LT4-Rx for a solid diagnosis of hypothyroidism and abruptly discontinued treatment. All subjects underwent weight, height, TSH, TPO, Tg-Abs and free T4 measurement and thyroid ultrasound on enrolment, 2-4 months later, and at the end of follow up. A TSH value of ≥4.5IU/mL was considered as underlying hypothyroidism. Results We enrolled 802 consecutive subjects (83% females) aged 48±16 (range 18-84 years) with 8.8±7.3 years on LT4-Rx. The treatment indications and corresponding percentage for LT4-Rx were classified as a nodule(s) (35%), indefinite (25%), post-partum (7%) and Hashimoto's (33%); 48% of subjects were part of Group A and long-term follow-up up to 5 years was achieved in the remaining. Among the entire cohort, n=182 subjects became hypothyroid, while the remaining n=620 remained euthyroid off LT4-Rx (23 vs. 77%, p&amp;lt;0. 001). On subgroup analysis, 40% of subjects comprising Group A became hypothyroid, whereas the corresponding value for Group B was 7%. In Group A, the reason for LT4-Rx, LT4 dose, LT4 dose/BMI, TSH levels and the presence of increased thyroid autoantibodies titers (ATA) were significantly different in those who became hypothyroid, whereas only the reason for LT4-Rx differed in Group B. Subjects with a diagnosis of nodules, negative ATA, lower TSH values and lower LT4 dose during treatment had significantly lower probability to become hypothyroid. Furthermore, in Group A, 14.8% became hypothyroid with baseline TSH&amp;gt;3IU/mL vs. 5.2% with baseline TSH&amp;lt;3IU/mL (p&amp;lt;0. 001); the corresponding values for Group B were 22.2% vs. 8.8%, (p&amp;lt;0. 001), respectively. Conclusions These findings suggest considerable overuse of thyroxine therapy. In cases of uncertainty, the existence of nodules, a low-normal TSH value, a relatively small T4 dose, and the absence of ATA are strong predictors of euthyroidism, and accordingly a treatment discontinuation trial is recommended. Furthermore, if hypothyroidism does not ensue 2-4 months post-treatment discontinuation, the likelihood to develop hypothyroidism in the long term is minimal.1. Livadas S, et al. Thyroid 2018. Presentation: Saturday, June 11, 2022 1:00 p.m. - 3:00 p.m.

ODP642 Differences in hormonal profiles and vitamin D status depending on the insulin sensitivity status in women with polycystic ovary syndrome (PCOS).

Abstract Background Depending on metabolic profile, two different PCOS phenotypes may be distinguished- the metabolic phenotype related to insulin resistance (IR) and the reproductive one, with persistent insulin sensitivity. Hyperandrogenemia, the main feature of PCOS, leads to increased visceral fat and muscle masses and thus to lower insulin sensitivity. In turn, IR leads to metabolic consequences and hormonal imbalance. Moreover, vitamin D deficiency, which is common in PCOS patients, is also associated with insulin resistance. Aim To compare the hormonal profiles and vitamin D status in women with PCOS depending on insulin sensitivity status. Materials and methods One thousand three hundred women with PCOS, aged 18 to 40, were recruited. The patients were divided into two groups depending on their insulin sensitivity status. Metabolic and hormonal parameters were assessed in subjects from each group. Blood samples were collected between the second and the sixth day of the menstrual cycle (follicular phase)for the quantification of hormonal parameters using the electrochemiluminescence immunoassay (ECLIA) methods or colorimetry. Results Patients with insulin resistance have a significantly higher concentration of DHEAS and TSH, higher Free Androgen Index, and significantly lower vitamin D concentration. Moreover, cortisol and estradiol concentrations are higher and prolactin is lower in patients with IR, but the differences are not statistically significant. There are no significant differences in the prevalence of Hashimoto disease between patients with IR and patients with persistent insulin sensitivity. Conclusions Metabolic phenotype of PCOS is associated with higher androgen concentration and higher TSH concentration compared to reproductive phenotype. Moreover, patients with PCOS and IR often have vitamin D deficiency compared to patients with persistent insulin sensitivity. Therefore the supplementation of vitamin D and regular TSH measurements are important in patients with metabolic PCOS phenotype. Presentation: No date and time listed

Medical cannabis for the treatment of comorbid symptoms in children with autism spectrum disorder: An interim analysis of biochemical safety.

Background: Autistic Spectrum Disorder (ASD) is a common neurodevelopmental disorder and no effective treatment for the core symptoms is currently available. The present study is part of a larger clinical trial assessing the effects of cannabis oil on autism co-morbidities. Objectives: The aim of the present study was to assess the safety of a CBD-rich oil treatment in children and adolescents with ASD. Methods: Data from 59 children and young adults (ages 5–25 years) from a single-arm, ongoing, prospective, open-label, one center, phase III study was analyzed. Participants received the Nitzan Spectrum® Oil, with cannabis extracts infused in medium chain triglyceride (MCT) oil with a cannabidiol:THC ratio of 20:1, for 6 months. Blood analysis was performed before treatment initiation, and after 3 months. Complete blood count, glucose, urea, creatinine, electrolytes, liver enzymes (AST, ALT, gamma glutamyl transferase), bilirubin, lipid profile, TSH, FT4, thyroid antibodies, prolactin, and testosterone measurements were performed at baseline, prior to starting treatment and at study midpoint, after 3 months of treatment. Results: 59 children (85% male and 15% female) were followed for 18 ± 8 weeks (mean ±SD). The mean total daily dose was 7.88 ± 4.24 mg/kg body weight. No clinically significant differences were found in any of the analytes between baseline and 3 months follow up. Lactate dehydrogenase was significantly higher before treatment (505.36 ± 95.1 IU/l) as compared to its level after 3 months of treatment (470.55 ± 84.22 IU/L) (p = 0.003). FT4 was significantly higher after 3 months of treatment (15.54 ± 1.9) as compared to its level before treatment (15.07 ± 1.88) (p = 0.03), as was TSH [(2.34 ± 1.17) and (2.05 ± 1.02)] before and after 3 months of treatment, respectively (p = 0.01). However, all these values were within normal range. A comparison of the group with additional medications (n = 14) to those who received solely medical cannabis (n = 45) showed no difference in biochemical analysis, including liver enzymes, which remained stable, except for change in potassium level which was significantly higher in the group that did not receive additional medications (0.04 ± 0.37) compared to the group receiving concomitant drug therapy (-0.2 ± 0.33) (p = 0.04). A comparison of patients who received a high dose of the cannabis oil (upper quartile-16 patients), with those receiving a low dose (lower quartile—14 patients) showed no significant difference between the two groups, except for the mean change of total protein, which was significantly higher among patients receiving high dose of CBD (0.19 ± 2.74) compared to those receiving a low dose of CBD (1.71 ± 2.46 (p = 0.01), and mean change in number of platelets, that was significantly lower among patients who received high dose of CBD (13.46 ± 31.38) as compared to those who received low dose of CBD (29.64 ± 26.2) (p = 0.0007). However, both of these changes lack clinical significance. Conclusion: CBD-rich cannabis oil (CBD: THC 20:1), appears to have a good safety profile. Long-term monitoring with a larger number of participants is warranted.

Association between thyroid function, nursing home admission and mortality in community-dwelling adults over 80 years

PurposeThyroid deficiency may reduce mortality in older adults, but older adults prioritize independence over merely staying alive. We investigated the association between thyroid dysfunction and nursing home admission and all-cause mortality in community-dwelling older adults over 80. MethodsWe conducted a retrospective population-based open cohort study using data from laboratory registries covering 75% of Denmark supplemented by national registries. We included all community-dwelling older adults over 80 years with a first TSH measurement between 1996 and 2019. Participants with prior thyroid disorders or medication affecting the thyroid were excluded. Participants were followed from inclusion until nursing home admission, death or loss to follow-up due to emigration. ResultsWe included 272,495 participants at baseline. Median follow-time was 3.71 years in analyses of nursing home admissions and 4.00 years for all-cause mortality. Hypothyroidism was associated with lower nursing home admission (TSH 5–10 mIU/l: HR 0.85, 95% CI: 0.80–0.91, P < 0.001); TSH >10 mIU/l HR 0.68, 95% CI: 0.54–0.85, P = 0.001) and with reduced all-cause mortality (TSH >10 mIU/l: HR 0.81, 95% CI: 0.70–0.93, P = 0.002). The association between hyperthyroidism and nursing home admission was of little clinical significance while hyperthyroidism was associated with increased all-cause mortality hazard both for low (HR 1.16, 95% CI 1.13–1.19, P < 0.001) and suppressed (HR 95% CI: 1.14 1.07–1.21, P < 0.001) TSH. Conclusion: Hypothyroidism is associated with a reduced nursing home admission hazard and to a lesser extent all-cause mortality in community-dwelling adults over 80 years, while hyperthyroidism is associated with increased all-cause mortality but not hazard of nursing home admission.

Effect of initial levothyroxine dose on neurodevelopmental and growth outcomes in children with congenital hypothyroidism

ObjectivesWe designed a multicentre open prospective randomized trial to evaluate the risk-benefit profile of two different initial treatment schemes with levothyroxine (L-T4), 10-12.5 μg/kg/day vs 12.6-15 μg/kg/day, on growth and neurodevelopmental outcomes in children with congenital hypothyroidism (CH) detected by neonatal screening to identify the best range dose to achieve optimal neurocognitive development.Design, patients and methodsChildren detected by neonatal screening were randomly assigned to receive an initial L-T4 dose of 10-12.5 μg/kg/day (Low) or 12.6-15 μg/kg/day (High). All patients underwent periodical clinical examination with measurement of growth parameters and measurement of TSH and FT4. Neurocognitive development was evaluated at the age of 24 months using Griffiths Mental Development Scales (GMDS) and cognitive and behavioral assessment was performed at 48 months of age using Wechsler Preschool and Primary scale of Intelligence (WIPPSI-III). The study was registered with clinicaltrials.gov (NCT05371262).ResultsTreatment schemes below or above 12.5 μg/kg/day were both associated with rapid normalization of TSH and thyroid hormone levels in most patients with no differences in the risk of over- and under-treatment episodes in the first months of life. Growth parameters were normal and comparable between the two groups. Developmental quotients at 24 months of age were normal in both groups (Low 100.6 ± 15.5 vs High 96.9 ± 16.6). Likewise, at 4 years of age IQ and subtest scores were comparable between patients from Low and High (Total IQ 104.2 ± 11.4 vs 101.0 ± 20.3, Verbal IQ 103.9 ± 11.5 vs 98.7 ± 15.1, Performance IQ 105.3 ± 10.4 vs 100.3 ± 19.8). 6/45 CH patients (13.3%) showed a total IQ below 85 (73.7 ± 5.9) regardless of age at diagnosis, L-T4 starting dose, time of FT4 and TSH normalization and episodes of over and undertreatment. Worse socioeconomic status and delayed bone age at diagnosis were the only predictors of an increased risk of having suboptimal IQ at 24 and IQ at 48 months.ConclusionsOur results indicate that initial treatment with L-T4, 10-12.5 μg/kg/day vs 12.6-15 μg/kg/day, are both associated with normal growth and neurodevelopmental outcomes in children with CH detected by neonatal screening. Further studies with a long-term follow-up on a larger number of patients are needed to confirm these results.Clinical trial registration https://clinicaltrials.gov/ct2/show/NCT05371262?term=NCT05371262&draw=2&rank=1 identifer NCT05371262.

Prevalence of thyroid dysfunction in neonates receiving parenteral nutrition in the intensive care unit

ObjectiveThe use of parenteral nutrition (PN) formulations that do not contain iodine can contribute to the deficiency of this mineral, potentially leading to hypothyroidism and, ultimately, neurocognitive impairments. This study aimed to evaluate TSH alterations in newborns receiving PN. MethodsRetrospective study of neonatal intensive care unit patients receiving PN for > 15 days. Nutritional, anthropometric, and biochemical variables (TSH, T4, CRP) were analyzed. Hypothyroidism was defined by TSH > 10 mU/L. ResultsTwo hundred newborns were evaluated [156 (78%) preterm, 31±5 weeks of gestational age, 112 (56%) with very or extremely low birth weight]. The median (IQR) hospital stay was 68 (42-110) days, PN duration was 31 (21-47) days, and 188 (94%) patients also received enteral nutrition. Overall, 143 (71.5%) newborns underwent at least one TSH measurement. The prevalence of hypothyroidism was 10.5%. The Median PN duration in this group was 51 (34-109) days. Among those with hypothyroidism, 10 received Lugol's solution and six levothyroxine. Thirteen patients received prophylactic Lugol's solution with a median PN duration of 63 (48-197) days. TSH levels correlated positively with PN duration (r = 0.19, p = .02). ConclusionsThe present data suggest that changes in TSH and T4 levels are present in neonates receiving PN for > 15 days, suggesting this population may be at risk for developing hypothyroidism. Therefore, the authors suggest that TSH and T4 measurements should be included as routine in neonatal patients receiving PN for > 15 days if PN formulations are not supplemented with iodine, and that iodine supplementation be provided as necessary.

A novel point-of-care device accurately measures thyrotropin in whole blood, capillary blood and serum.

Point-of-care (POC) measurement of thyrotropin (TSH) may facilitate prompt diagnosis of thyroid dysfunction. We evaluated the analytical performance of a new POC TSH assay (Wondfo). TSH measurements were made from 730 consecutive, unselected subjects in an outpatient setting, using Wondfo in whole blood, capillary blood and serum or automated reference equipment (serum only). TSH measurements were user-independent. Total intra-and inter-assay variation (CV%) was 12.1 and 16.2%, respectively. Total CV% was 10.6-22.6% and 14.5-21.6% in serum and whole blood, respectively. Linearity was very good. Recovery rate was 97-127%. Prolongation of incubation time increased TSH results of 12% (13%) and 33% (35%) after 2 and 5 additional minutes in serum (blood), respectively. When measured simultaneously in two Wondfo devices, the slope of the regression line was 1.03 (serum) and 1.02 (blood), with Spearman's correlation of 0.99 for both. TSH measurements between Wondfo and reference correlated strongly (r=0.93-0.96), though TSH measurements were lower with Wondfo (slopes of plots of measurements made using the two devices were 0.94 [serum vs. serum]; 0.83 [whole blood vs. serum] and 0.64 [capillary blood vs. serum]). Depending on sample material, TSH in capillary blood was lower vs. whole blood (slope: 0.82) and for whole blood vs. serum (Wondfo and reference method; slope: 0.69 and 0.83). Total haemolysis, but not elevated bilirubin or lipemia, disrupted TSH measurement. The Wondfo system was straightforward to use without need for specialist technicians and demonstrated analytic performance suitable for clinical use for the diagnosis of thyroid dysfunction.

The prevalence of hypothyroxinemia in premature newborns.

Congenital hypothyroidism diagnosed by TSH assessment in bloodspot screening may be overlooked in preterm newborns due to immaturity of the hypothalamus-pituitary-thyroid axis in them. The purpose of the study was to determine the prevalence and causes of hypothyroxinemia in preterm newborns, determined by TSH and FT4 serum concentration measurement, performed on the 3-5th day of life. We assessed TSH, FT4 and FT3 serum concentration on the 3-5th day of life in preterm children born at our centre within three consecutive years. We assessed the incidence of hypothyroxinemia, and its cause: primary hypothyroidism, secondary hypothyroidism or low FT4 syndrome - with normal TSH concentration, its dependence - among others - on gestational age (GA), birth body weight (BBW) and being SGA. A total of 525 preterm children were examined. FT4 concentration was decreased in 14.9% of preterm newborns. The most frequent cause of hypothyroxinemia was low FT4 syndrome (79.5%). More than 92% cases of hypothyroxinemia occurred in children born before the 32nd week and/or with BBW below 1500 g. Thus, every fourth child in these groups had a reduced FT4 concentration. Neonates with hypothyroxinemia were significantly lighter than those with normal FT4. In older and heavier neonates with hypothyroxinemia, serious congenital defects were observed. Neither IVH nor SGA nor twin pregnancies predispose children to hypothyroxinemia. Among newborns with untreated hypothyroxinemia in whom TSH and FT4 assessment was repeated within 2-5 weeks, a decreased FT4 concentration was confirmed in 56.1% of cases. As hypothyroxinemia affects 25% of newborns born before the 32nd week of gestation and those in whom BBW is less than 1500g, it seems that in this group of children the newborn screening should be extended to measure serum TSH and FT4 concentration between the 3-5th day of life. In older and heavier neonates, additional serum TSH and FT4 assessment should be limited to children with severe congenital abnormalities but not to all SGA or twins. Despite the fact that the most common form of preterm hypothyroxinemia is low FT4 syndrome, it should be emphasized that FT4 remains lowered on subsequent testing in more them 50% of cases.