Low T4 Levels Research Articles

Thyroid hormone decreasing after mechanical thrombectomy for cerebral infarction

ObjectiveMechanical thrombectomy (MT) is an established treatment for large vessel occlusion in patients with cerebral infarction. The use of iodine contrast agent decreases thyroid hormone levels via the Wolff−Chaikoff effect. Low triiodothyronine (T3) syndrome caused due to severe illness status can contribute to decreased levels of thyroid hormones. Reportedly, a low T3 level is associated with poor prognosis in patients with cerebral infarction. This study aimed to clarify the changes in thyroid hormone levels in the acute phase after MT and the effects of the iodine contrast agent on these hormones. MethodsThis was a single-center, prospective, and single-arm trial. Thyroid stimulating hormone (TSH), free T3 (FT3), and free T4 (FT4) levels were tested on admission and 24 h postoperatively in patients who were approved for MT. ResultsA total of 37 patients were screened during the study period and 31 patients were enrolled in this study. Significant decreases were observed in TSH (P < 0.001) and FT3 (P < 0.001) levels 24 h after MT. Moreover, there was a correlation between the decrease in ratio of change in FT3 levels and the amount of iodine contrast agent used per body surface area (r = 0.43, P = 0.019), while no such correlations were detected for TSH and FT4. ConclusionWe demonstrated that TSH and FT3 levels decreased in the acute phase after MT and that FT3 levels were associated with the amount of iodine contrast agent used.

Selpercatinib-Induced Hypothyroidism Through Off-Target Inhibition of Type 2 Iodothyronine Deiodinase.

The development of the selective RET inhibitors selpercatinib and pralsetinib has revolutionized the treatment of metastatic progressive RET-mutant medullary thyroid carcinoma (MTC) and other RET-driven cancers, given their more favorable side-effect profile. The aim of this study is to investigate the mechanisms of selpercatinib-induced thyroid dysfunction in athyreotic patients with RET-mutant MTC and in patients with RET-mutant non-small-cell lung cancer (NSCLC) who had a functional thyroid. Thyroid hormone levels were evaluated in an observational cohort of five athyreotic patients with MTC and 30 patients with NSCLC before and after initiation of selpercatinib. In vitro experiments to identify the mechanism of selpercatinib-induced thyroid dysfunction were conducted in cells expressing endogenous D1, D2, and D3 iodothyronine deiodinases. Upon initiating treatment with selpercatinib, athyreotic patients developed clinical hypothyroidism with approximately 60% lower T3 levels despite adequate levothyroxine supplementation, whereas in patients with NSCLC, who retain a normal thyroid, selpercatinib resulted in a more attenuated reduction in serum T3, which was dose-dependent. We conducted studies in cells endogenously expressing either D1, D2, or D3, the three iodothyronine deiodinases. Selpercatinib inhibited D2-mediated T3 production in MSTO-211 cells by 50%. A modest repression of D2 mRNA was present in human thyroid cancer TT cells that express RET, but not in the MSTO-211 cells that do not. No effect of the drug was observed on D1 (activating deiodinase) or D3 (inactivating deiodinase). Thus, a nontranscriptional effect of selpercatinib on D2 activity is the most plausible explanation for the low T3 levels. An off-target effect of selpercatinib on D2-mediated T3 production leads to clinical hypothyroidism, primarily in levothyroxine-treated athyreotic patients. Liothyronine supplementation was needed to achieve normal T3 levels and restore clinical euthyroidism.

Thyroid status in children with severe acute malnutrition

Objectives: The objective of the study is to study thyroid hormone levels in children with severe acute malnutrition (SAM) and its correlation with serum total protein and albumin levels. Materials and Methods: A prospective cross-sectional study was carried out at Nutritional Rehabilitation Centre, Hubli, from Dec 2018 to Nov 2019. Inclusion criteria: All children in the age group of 6–59 months with SAM. Exclusion criteria: (i) Children suffering from metabolic disorders, tuberculosis, urinary tract infection, malabsorption syndrome (celiac disease), protein losing enteropathy, and nephrotic syndrome; (ii) Children with major congenital anomalies; and (iii) Children with chronic liver and kidney diseases. All enrolled children’s details of demography, clinical history, and examination were entered in a predesigned pro forma. Total triiodothyronine (TT3), total thyroxine (TT4), thyroid-stimulating hormone (TSH), and serum total protein and albumin were estimated. Data were analyzed using SPSS Version 16. Results: Total of 50 children fulfilled criteria during study period. Mean age of presentation was 18 ± 2.1 months with male-to-female ratio 0.8:1. The mean TT3 (ng/dl), TT4 (mcdg/l), and TSH (mIU/L) were 109.8 ± 50.6, 8.36 ± 3.7, and 2.5 ± 1.8, respectively. Mean total protein and albumin were 5.5 ± 1.4 g/dl and 2.97 ± 0.9 g/dl. Overall, 18 (36%) children had low total protein and 17 (34%) have low serum albumin. Low serum TT3, and TT4 levels were found in 11 (22%) and 14 (28%), respectively, and elevated TSH in 4 (8%) children. Low T3 was significantly associated with low albumin (P &lt; 0.01). Conclusion: The impaired thyroid function and low serum T3 levels seen in SAM children were probably an adaptive change to malnutrition.

Abstract 81: A case report of elevated TSH, elevated T3 and low T4 levels and mutation in SLCA5A gene: A diagnostic dilemma

Background: Iodide transport defect (ITD) is one of the causes of thyroid dyshormonogenesis. It is an uncommon disorder which is mediated by NIS mutations. They present with hypothyroidism and goitre due to the absence of active transport of iodide into the thyroid gland. The clinical presentation of patients with ITD due to different mutations of NIS gene has been described: including T354P, G395R, Q267E, and G543E mutations.Case Report: A 10-year-old boy born out of non – consanguineous marriage, with no antenatal, postnatal complications presented with history of goitre for 7 years. The child had a history of ADHD, average scholastic performance, and history of weight gain of 4-5 kilograms over past 2 months. Mother was diagnosed to have hypothyroidism during pregnancy. His Thyroid profile showed FT4 – 0.413 ng/dL, FT3 – 6.06 pg/mL, TSH – 12.75 mIU/mL and USG neck showed mild thyromegaly. A genetic analysis was done which revealed a homozygous mutation on Exon 7 in SLC5A5 gene. Child was started on Levothyroxine supplementation.Conclusion: The clinical picture is suggestive of hypothyroidism with elevated free T3 levels. This genetic mutation needs to be followed up in the global data base to ascertain its significance in future.

Worse Outcomes in Patients With Depression Linked to Low Thyroid Hormones

Worse Outcomes in Patients With Depression Linked to Low Thyroid Hormones

The Tri-iodothyronine (T3) Level Is a Prognostic Factor for Patients With Advanced NSCLC: Receiving Immune Checkpoint Inhibitors and Is Associated With Liver Metastasis.

Endocrine hormones influence tumor progression and the response to treatment. Despite the importance of immune checkpoint inhibitors (ICIs) as treatments for advanced non-small cell lung cancer (NSCLC), few studies have explored the effects of hormone levels in NSCLC patients on the effectiveness of ICI therapies. We thus investigated the effects of baseline blood markers in patients with advanced NSCLC on ICI treatments. Patients with advanced NSCLC who received programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) inhibitors at Chungnam National University Hospital between December 2016 and November 2020 and who lacked any history of thyroid gland-related diseases were analyzed retrospectively. We collected clinical information and baseline laboratory data, including the levels of endocrine hormones, cytokines, complete blood counts (CBCs), and peripheral blood chemistry panels. We explored the relationships of hormone levels with clinical outcomes (overall survival [OS], progression-free survival [PFS], and best response), liver metastasis, and blood markers using the Kaplan-Meier method, Cox's proportional hazards regression, and logistic regression. A total of 113 patients were enrolled. A shorter PFS was independently associated with liver metastasis, higher cortisol levels, and lower hemoglobin (Hb) levels; a shorter OS was associated with liver metastasis, lower tri-iodothyronine (T3) levels, higher lactate dehydrogenase (LDH) levels, and lower albumin levels. Patients with low T3 levels exhibited a shorter PFS and OS, and a poorer best response. Patients with low T3 levels tended to have higher disease progression rates, lower levels of adrenocorticotropic hormone (ACTH), C-peptide, albumin, Hb, and neutrophil-to-lymphocyte ratio, and higher levels of interleukin (IL)-6, white blood cells, platelets, compared with those with normal T3 levels. We found a significant association between a low T3 level and liver metastasis. We found the baseline T3 level was associated with both prognosis and the response to ICIs in patients with advanced NSCLC, probably reflecting impaired liver function and systemic inflammation induced by the interaction of T3 with other biomarkers, such as IL-6, ACTH, cortisol, C-peptide, Hb, LDH, and albumin.

Evaluating Thyroid Function in Paediatric Nephrotic Syndrome in a Tertiary Care Hospital of Northern India: A Case-control Study

Introduction: Nephrotic Syndrome (NS) is a glomerular disease characterised by oedema, hypoalbuminaemia and substantial proteinuria, which includes loss of thyroxine binding globulin and thyroid hormones, often resulting in subclinical or overt hypothyroidism. Studies reporting on the relationship between NS and thyroid dysfunction elude consensus. Aim: To evaluate Triiodothyronine (T3), Thyroxine (T4) and Thyroid Stimulating Hormone (TSH), and lipid levels to identify clinical predictors of thyroid dysfunction in paediatric cases of NS. Materials and Methods: A hospital based case-control study was undertaken on 100 children, attending Paediatric Nephrology Clinic, from October 2020 to March 2021.Patients were divided into two groups: 50 cases under various stages of nephrotic syndrome, and 50 healthy controls in the age group of 1 to 18 years, of either gender. Investigations on serum creatinine, Haemoglobin (Hb), white blood cell count, platelet count, serum T3, T4, TSH, and blood lipids like: Triglyceride (TG), Total Cholesterol (TC) and Low Density Lipoprotein (LDL), were performed on all the children, and compared for analysis of corresponding data of cases and controls. Statistical analysis was carried out using ANOVA test. Results: The mean age of the cases and controls was 12.6±4.2 and 11.8±4.0 years, respectively. Mean T3 value in the case group was 117±63 ng/dL, and in control was 176±95 ng/ dL (p=0.104). Mean T4 value among the case group (9.9±5.1 μg/dL) was significantly lower than that of controls (14.2±8.4 μg/dL) (p=0.016). The difference of TSH levels in the case group was 3.8±2.9 μIU/mL, and control was 2.5±2.2 μIU/mL (p&lt;0.001). Hypothyroidism was observed in 9 (45%) children with first episode, 7 (53.84%) in remission, and 6 (60%) relapsed patients. Conclusion: Urinary losses of binding proteins such as Thyroxine Binding Globulin (TBG), transthyretin or prealbumin and albumin, may have caused lower levels of T3 and T4 and higher value of TSH. T3, T4 and TSH are important clinical predictors of thyroid dysfunction in patients with NS, therefore hypothyroidism should be investigated in all children with NS.

Myxedema coma associated with Covid-19 infection: case report

The coronavirus disease 2019 pandemic continues to exert a significant impact on global health care systems, causing devastating mortality and morbidity. As time passes and our understanding of this novel respiratory virus deepens, it is increasingly clear that its effects extend beyond that of the respiratory system. The link with endocrine disorders was noticed quite early when it was found that patients with diabetes and uncontrolled hyperglycemia were at an increased risk of severe disease as well as mortality from COVID-19. However, the other endocrine manifestations of COVID-19 probably were more subtle and information about them emerged more gradually over a period of time. Thyroid diseases are common endocrine disorders, and accordingly, a lot of attention has gone into the study of how COVID-19 affects the thyroid. Although the majority of mild to moderate COVID-19 patients remain euthyroid, a significant proportion of those with severe disease manifest with abnormalities in thyroid function. These manifestations include low thyroid stimulating hormone and low T3 levels, whereas low T4 levels were observed less commonly. Apart from this, several reports of subacute thyroiditis following COVID-19 have also been published. Similarly, Graves’ disease has been reported to occur in patients who had recovered from COVID-19. We present a case of a 55-year-old woman who presented to the emergency department and her physical examinations and laboratory results were significant for myxedema coma and the patient was given levothyroxine with improvement of symptoms and mild change in thyroid hormone levels during hospitalization.

Thyroid Dysfunction in Patients with Liver Cirrhosis and its Association with the Severity of Liver Disease: A Cross-sectional Study

Introduction: There exists a complex relation between the thyroid hormones and liver physiology in health and disease. The liver along with the thyroid gland play a significant role in the conversion of inactive Thyroxine (T4 ) to active Triiodothyronine (T3 ). The most common thyroid hormone profile in cirrhosis of liver is a low total T3 and free T3 , secondary to reduced activity of deiodinase type 1 and increased conversion to rT3 . Aim: To assess the association between the thyroid hormone levels and severity of liver disease, expressed in terms of child pugh score in tertiary care hospital in Goa. Materials and methods: The cross-sectional observational study included hundred patients with liver cirrhosis, admitted at a tertiary care hospital in Goa, from October 2019 to September 2020. The thyroid hormone levels were estimated from an early morning fasting blood sample within 24 hours of admission, once the patient satisfied the inclusion criteria. The Child Turgott Pugh scoring system was used to classify patients as per their severity of liver disease. The data was entered and analysed in Statistical Package for Social Sciences (SPSS) software version 14.0. Results: There were 95 males and 5 females. The study showed low mean levels of total T4 and free T3 in patients with cirrhosis of liver, which was significantly associated with Child Pugh classes of liver dysfunction. There was an association between levels of free T3 and the classes of Child Pugh score. The difference in the mean levels of TSH, total T3 and free T4 across the Child Pugh classes were not statistically significant. Conclusion: The study showed low free T3 levels in patients with cirrhosis of liver as seen in similar studies done in various settings. Thus, Thyroid Function Tests (TFTs) especially free T3 levels have a considerable potential to be used an independent predictor or a proxy to prognosis in patients with liver cirrhosis.

To study thyroid hormone levels (FT3, FT4, and TSH levels) in critically ill children and their correlation with disease severity and clinical outcome in Rajendra Institute of Medical Sciences, Ranchi, Jharkhand.

There are manifold effects on neuro-endocrine and metabolic systems due to critical illness. Abnormalities in thyroid hormone levels in a critically-ill patient with no pre-existing hypothalamo-pituitary-thyroid dysfunction is seen in Euthyroid sick syndrome or Non thyroidal illness syndrome. The understanding of different endocrinal changes in acute phase of critical illness may help us to intervene early and improve by pharmacological intervention. Critically ill children admitted in PICU, RIMS, Ranchi, aged 29 days to 17 years. In our study, it was seen that FT3 and FT4 were low at admission at admission in critically ill children. And among them, the non-survivors had significantly lower values compared to survivors. Among this critically ill patient, more than 70% of patients have shown low free T3 (Type I NTIS) and around 50% of low free T4 levels and free T3 levels (Type II NTIS). We have done this study to assess the thyroid dysfunction in critically ill children admitted in our PICU and its correlation with disease severity and clinical outcome.

STUDY ON THYROID ABNORMALITY AMONG CHRONIC KIDNEY DISEASE PATIENTS

Chronic Kidney Disease is a worldwide health problem with an increasing incidence and prevalence. Abnormalities in the structure and function of the thyroid gland and in the metabolism and plasma concentration of thyroid hormones are common in patients with Chronic Kidney Disease. Patients with CKD having many signs and symptoms suggestive of thyroid dysfunction like sallow complexion, edema, dry skin, cold intolerance, decreased BMR, asthenia and hyporeexia. So in cases of CKD, it is difcult to exclude thyroid dysfunction on mere clinical background. Total number of 100 patients with Chronic Kidney Disease were selected in this prospective study. 100 patients with Chronic Kidney Disease (CKD) fullling the criteria for CKD who were on conservative management were studied, among these 100 patients 70 were male and 30 were female Among the 100 patients in our study 55 of them had low serum T3 levels (55%), 17 patients among the low serum T3 level also had high TSH value of &gt;20 ILIU/m1 with low T4 levels and also symptoms suggestive of hypothyroidism.

Thyroid Disorders.

Thyroid Disorders.

Effects of hormonal changes on sarcopenia in chronic kidney disease: where are we now and what can we do?

Sarcopenia or muscle wasting is a progressive and generalized skeletal muscle disorder involving the accelerated loss of muscle mass and function, often associated with muscle weakness (dynapenia) and frailty. Whereas primary sarcopenia is related to ageing, secondary sarcopenia happens independent of age in the context of chronic disease states such as chronic kidney disease (CKD). Sarcopenia has become a major focus of research and public policy debate due to its impact on patient's health‐related quality of life, health‐care expenditure, morbidity, and mortality. The development of sarcopenia in patients with CKD is multifactorial and it may occur independently of weight loss or cachexia including under obese sarcopenia. Hormonal imbalances can facilitate the development of sarcopenia in the general population and is a common finding in CKD. Hormones that may influence the development of sarcopenia are testosterone, growth hormone, insulin, thyroid hormones, and vitamin D. Although the relationship between free testosterone level that is low in uraemic patients and sarcopenia in CKD is not well‐defined, functional improvement may be seen. Unlike testosterone, it is known that vitamin D is associated with muscle strength, muscle size, and physical performance in patients with CKD. Outcomes after vitamin D replacement therapy are still controversial. The half‐life of growth hormone (GH) is prolonged in patients with CKD. Besides, IGF‐1 levels are normal in patients with Stage 4 CKD—a minimal reduction is seen in the end‐stage renal disease. Unresponsiveness or resistance of IGF‐1 and changes in the GH/IGF‐1 axis are the main causes of sarcopenia in CKD. Low serum T3 level is frequent in CKD, but the net effect on sarcopenia is not well‐studied. CKD patients develop insulin resistance (IR) from the earliest period even before GFR decline begins. IR reduces glucose utilization as an energy source by hepatic gluconeogenesis, decreasing muscle glucose uptake, impairing intracellular glucose metabolism. This cascade results in muscle protein breakdown. IR and sarcopenia might also be a new pathway for targeting. Ghrelin, oestrogen, cortisol, and dehydroepiandrosterone may be other players in the setting of sarcopenia. In this review, we mainly examine the effects of hormonal changes on the occurrence of sarcopenia in patients with CKD via the available data.

THE IMPORTANCE OF THYROID HORMONE LEVELS AFTER HEART SURGERY – PRELIMINARY STUDY

Introduction Thyroid hormone level suppression after serious operations as coronary artery bypass graft (CABG) surgery, and aortic valve replacement (AVR) is a quite common phenomenon. It is called the nonthyroidal illness syndrome. This appears with a decrease in triiodothyronine (T3) and tetra iodothyronine (T4) serum levels with no thyroid disorders in the medical history. Our aim was to investigate the relationship among thyroid hormone levels and postoperative complications after CABG and AVR. Methods This single center retrospective, observational study approved by the IRB (65/2017). 49 patients, who underwent CABG or AVR, were enrolled in our study between the 1st of January 2019 and the 16th of February 2021. Demographic parameters, Euroscore, thyroid disorders, T3, T4 levels in the first postoperative week, the perioperative thyroxine supplementation and the vasopressor- inotropic needs were summarized in our database. Our primary outcome was 1-year mortality, secondary outcome was the length of stay in the intensive care unit (ICU). Spearman's correlation and Cox-regression analysis were used for the statistical analysis. Results Final analysis included 49 patients, 9 (18.4%) were female. The median survival time was 584 days (IQR25-75: 571-614). Five of the 49 patients (10.2%) died until the 16th of February 2021. Seven patients (14.3%) stayed in ICU for more than 72 hours. Four patients (8.2%) were treated with thyroxine in the postoperative period whom did not have preoperative thyroid dysfunction. None of the patients had hypothyroidism nor hyperthyroidism in their medical history. 17 patients (34.7%) had low T3 levels while, none of the patients had low T4 levels on the 1st or 2nd postoperative day. Association was found between the lengths of stay in the ICU and low T4 levels (p=0.048) using nonparametric test. The actual change in T4 levels between the first and the second sample during first postoperative week showed a significant association with 1-year mortality (OR: 1.17; 95%CI: 1.04-1.31; p=0.007). Discussion Our results highlight the role of thyroid function in the postoperative period. The decrease of T4 levels have independent relationship with adverse outcomes as 1-year mortality and the lengths of ICU stay. Thyroid function monitoring could be a beneficial after CABG and AVR operations.

Low striatal T3 is implicated in inattention and memory impairment in an ADHD mouse\xa0model overexpressing thyroid hormone-responsive protein

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder, potentially with a biological basis; however, its exact cause remains unknown. Thyroid hormone (TH) abnormalities are more prevalent in patients with ADHD than in the general population, indicating a shared pathogenetic mechanism for these conditions. Previously, we identified that overexpression of thyroid hormone-responsive protein (THRSP), a gene highly responsive to TH status, induced inattention in male mice. Herein, we sought to explore whether TH function in THRSP-overexpressing (THRSP OE) mice influences ADHD-like (inattention) behavior. We now confirm that THRSP overexpression in male mice reproduces behavioral features of ADHD, including sustained inattention and memory impairment, accompanied by excessive theta waves that were found normal in both the THRSP-knockout and hetero groups. Physiological characterization revealed low striatal T3 levels in the THRSP OE mice due to reduced striatal T3-specific monocarboxylate transporter 8 (MCT8), indicating brain-specific hypothyroidism in this transgenic mouse strain. TH replacement for seven days rescued inattention and memory impairment and the normalization of theta waves. This study further supports the involvement of the upregulated THRSP gene in ADHD pathology and indicates that THRSP OE mice can serve as an animal model for the predominantly inattentive subtype of ADHD.

Analysing Biochemical Parameters and Developing Risk Prediction Models in Patients with Schizophrenia and Bipolar Disorder

Objectives: The aim of this study is to analyze biochemical parameters and develop risk prediction models in patients with schizophrenia and bipolar disorder. Methods: Biochemical values of 65 schizophrenia and 65 bipolar disorder patients were statistically compared by analyzing thyroid function tests (TSH, T3 and T4), 25-0H vitamin D3, calcium, ferritin, iron, folate, vitamin B12, and magnesium levels. Risk analysis of the control group was evaluated in line with the obtained findings. Results: Male patients diagnosed with schizophrenia were observed to have lower T3 level than that of control group (p<0.001). Vitamin B12 value and Ferritin levels of male patients diagnosed with bipolar disorder were higher than those of control group (p<0.05), while their T3 levels were lower comparing to control group (p<0.001). Female patients diagnosed with schizophrenia were observed to have higher Ferritin levels (p<0.05) and lower T3 levels comparing to control group (p<0.001). When female patients diagnosed with bipolar disorder were compared with control group, their Ferritin levels and T4 levels were observed to be higher (p<0.05). Conclusion: Unless an intervention is made by detecting vitamin deficiency, the treatment may fail with psychotropic medications. In psychotic symptoms, in addition to antipsychotic treatment, replacement of low serum vitamin level may have positive effects on recovery. Therefore, serum vitamin B12, T3, T4 and TSH hormones, and ferritin levels can be recommended to be used as routine screening tests especially in the first applications of psychiatric patients with cognitive disorders.

The Correlation Between Low Serum T3 Levels and All-Cause and Cardiovascular Mortality in Peritoneal Dialysis Patients.

ObjectiveThis study is to investigate the correlation between serum triiodothyronine (T3) levels and all-cause and cardiovascular mortality in PD patients.MethodsA total of 376 end-stage renal disease (ESRD) patients who started maintenance PD treatment in the Department of Nephrology in our hospital and stable treatment for ≥3 months were selected, and the total T3 (TT3) and free T3 (FT3) levels were determined. Among them, 168 cases with FT3 <3.5 pmol/L and/or TT3 <0.92 nmol/L were divided into the low serum T3 level group, and the remaining 208 cases were divided into normal serum T3 level group. The Cox survival analysis method was used to analyze the correlation between low serum T3 levels and all-cause and cardiovascular mortality in PD patient.ResultsCompared with the normal serum T3 level group, patients with low serum T3 levels had higher systolic blood pressure and a higher proportion of heart disease, and lower levels of total T4, free T4, hemoglobin, serum albumin, blood calcium, serum total bilirubin, alanine aminotransferase, and 24-h urine volume (all P < 0.05). Binary Logistic regression analysis showed that heart disease (P = 0.003, OR: 2.628, 95% CI: 1.382–4.997) and high TT4 level (P < 0.001, OR: 0.968, 95% CI: 0.956–0.979) were related to low serum T3 levels in PD patients. Multivariate Cox regression analysis showed that low serum FT3 level was an independent risk factor for all-cause death in PD patients (HR = 0.633, 95% CI = 0.431–0.930; P < 0.020).ConclusionLow serum T3 levels in PD patients were associated with heart disease and TT4 levels. Low serum FT3 levels were associated with the risk of all-cause death in PD patients.

Thyroid function and immune status in perch (Perca fluviatilis) from lakes contaminated with PFASs or PCBs

The environment contains a multitude of man-made chemicals, some of which can act as endocrine disruptors (EDCs), while others can be immunotoxic. We evaluated thyroid disruption and immunotoxic effects in wild female perch (Perca fluviatilis) collected from two contaminated areas in Sweden; one site contaminated with per- and polyfluoroalkyl substances (PFASs) and two sites contaminated with polychlorinated biphenyls (PCBs), with one reference site included for each area. The hepatic mRNA expression of thyroid receptors α and β, and the thyroid hormone metabolising iodothyronine deiodinases (dio1, dio2 and dio3) were measured using real-time PCR, while the levels of thyroid hormone T3 in plasma was analysed using a radioimmunoassay. In addition, lymphocytes, granulocytes, and thrombocytes were counted microscopically. Our results showed lower levels of T3 as well as lower amounts of lymphocytes and granulocytes in perch collected from the PFAS-contaminated site compared to reference sites. In addition, expressions of mRNA coding for thyroid hormone metabolising enzymes (dio2 and dio3) and thyroid receptor α (thra) were significantly different in these fish compared to their reference site. For perch collected at the two PCB-contaminated sites, there were no significant differences in T3 levels or in expression levels of the thyroid-related genes, compared to the reference fish. Fish from one of the PCB-contaminated sites had higher levels of thrombocytes compared with both the second PCB lake and their reference lake; hence PCBs are unlikely to be the cause of this effect. The current study suggests that lifelong exposure to PFASs could affect both the thyroid hormone status and immune defence of perch in the wild.

Low Tri-iodothyronine Syndrome Improves the Risk Prediction for Mortality in Patients with Acute Heart Failure: A Prospective Observational Cohort Study

Background and Objective: Clinical studies have suggested that low tri-iodothyronine (T3) syndrome negatively affects the clinical outcomes of patients with acute heart failure (AHF). The aim of this prospective cohort study was to evaluate the effect of low T3 syndrome in terms of prognosis and risk-predictive potential in AHF. Methods: A prospective observational cohort study was conducted from April 2012 to August 2016 in Nanjing, China. All clinical baseline characteristics were retrieved from electronic medical records. Low T3 syndrome was defined by a low free T3 level (

T3 as predictor of mortality in any cause non-critically ill patients.

BackgroundLow T3 syndrome refers to a set of thyroid hormone metabolism alterations present in the disease state. A correlation between low T3 and poor clinical outcomes in the intensive care unit is more established. Nonetheless, studies on non-critically ill patients are few and controversial.ObjectiveTo evaluate the prevalence and predictive value of low T3 levels on 30-day and 6-month mortality in non-critically ill patients. Secondary outcomes evaluated the length of hospital stay, overall mortality, and hospital readmission.DesignProspective cohort study.MethodsA total of 345 consecutive patients from the Internal Medicine ward of a tertiary hospital in southern Brazil were included and followed from October 2018 to April 2019 (6 months). Levels of total serum T3 were measured weekly, from admission to discharge, and correlated with 30-day and 6-month mortality.ResultsPrevalence of low T3 was 36.6%. Low T3 levels were associated with higher 30-day hospital mortality (15.1% vs 4.1%, P < 0.001) and higher 6-month overall mortality (31.7% vs 13.2%, P < 0.001). Total serum T3 at admission was an independent predictor of 30-day hospital mortality.ConclusionLow T3 levels are a prevalent condition among non-critically ill patients, and this condition is associated with poor clinical outcomes in this population. Total serum T3 levels, alone or in association with other predictive scores, were demonstrated to be an easy and valuable tool for risk stratification and should be further employed in this setting.