FT4 Concentrations Research Articles

EFFECT OF SUBCLINICAL HYPOTHYROIDISM ON MATERNAL AND PERINATAL OUTCOME

Background:Adverse maternal outcomes and perinatal complications are closely associated with overt maternal hypothyroidism, but whether these complications occur in women with subclinical hypothyroidism (SCH) during pregnancy remains controversial.The aim of this study was to evaluate the effects of SCH on maternal and perinatal outcomes during pregnancy. Methods:This retrospective cohort study was conducted by examining the pregnant women who applied to the Gynaecology Department of Hind Institute of Medical Sciences and Hospital at their 6th to 14th gestational weeks and had antenatal follow-ups between February 1, 2021 and December 31, 2022. Results: The TSH concentration was significantly lower in the first trimester than in the third trimester (P,0.001). The fT4 concentration was higher in the first trimester than in the second and third trimesters (P,0.001). The incidences of GH and PROM were significantly higher in women with SCH than in euthyroid women (5% vs. 1.57%, P= 0.020 10% vs. 5%, P= 0.002).IUGR was more frequent in women with SCH than in euthyroid women (7.5% vs. 1.3%, P,0.001). More LBW infants were delivered in the SCH group than in the euthyroid group (12.5% vs. 5%, P,0.001). Conclusion:The results of this study indicate that pregnant women with SCH had increased risks of GH and PROM, and their foetuses and infants had increased risks of IUGR and LBW. Thus, routine maternal thyroid function testing is necessary to improve maternal and perinatal outcomes.

Clinical Study of Liver Cirrhosis with Special Reference to Thyroid Function: A Cross Sectional Study

Objective: The objective of this study was to assess liver cirrhosis with special reference to thyroid function. Study Design: The study was a cross-sectional one. Setting: Research was conducted at Department of Medicine, Shaikh Zayed Hospital, Lahore from August 2022 to January 2023. Material and Methods: In this study, 115 patients with cirrhosis who were both male and female and between the ages of 20 and 70 were included. These patients underwent thyroid function tests. Each patient provided written informed consent. Results: The average patient's age was 51.78±9.17 years old, and their ages ranged from 35 to 70. The vast majority of patients (n=119, or 55.6%) were between the ages of 53 and 70. Patients included 71 males (61.73% of the total) and 44 females (38.8%). The average duration of illness was 23.78 ±10.05 months, although it may be as little as 8 months. A total of 34 patients (29.56%) were classified as Child Class-B, while 81 patients (70.43%) were classified as Child Class-C. The range of serum TSH was from 3.5 to 5.8 uIU/ml (mean 4.32±0.43 uIU/ml), while the range of serum fT3 was from 1.2 to 2.9 pg/ml (mean 1.87± 0.38 pg/ml). The average serum fT4 concentration was 1.68 pg/ml (standard deviation = 0.47). Practical Implication: Especially in low and middle income countries, there is a lack of consistent data on the impact of cirrhosis on thyroid function and the association of thyroid hormone levels in patients with cirrhosis. In order to better understand the medical picture of cirrhosis of the liver and its relationship to thyroid function, the current investigation was carried out at a tertiary care center. Conclusion: Liver cirrhosis patients had lower mean blood levels of fT3 and fT4. However, the mean serum TSH level was higher in this group of individuals. It was shown to be significantly higher in patients with more advanced liver disease, but not to differ significantly by age, gender, or disease duration. Keywords: Thyroid Function, Liver Cirrhosis, Child-Pugh Classification

Trimester-specific reference intervals for thyroid function parameters in pregnant Caucasian women using Roche platforms: a prospective study

BackgroundStandard thyroid function parameters reference intervals (RI) are unsuitable during pregnancy, potentially resulting in incongruous treatments that may cause adverse effects on pregnancy outcomes. We aimed at defining trimester-specific TSH, FT4 and FT3 RI, using samples longitudinally collected from healthy Caucasian women.Materials and methodsBlood samples from 150 healthy Caucasian women, who had a physiological gestation and a healthy newborn at term, were collected in each trimester and at around six months post-partum. They showed mild iodine deficiency. After excluding women with overt TSH abnormalities (> 10 mU/L) and/or TPO antibodies, data from 139 pregnant women were analyzed by means of widely used Roche platforms, and TSH, FT4 and FT3 trimester-specific RI were calculated. Post-partum data were available for 55 subjects.ResultsSerum TSH RI were 0.34–3.81 mU/L in the first trimester, and changed slightly to 0.68–4.07 U/L and 0.63–4.00 mU/L in the second and third trimester, respectively. Conversely, both FT4 and FT3 concentrations progressively decreased during pregnancy, the median values in the third trimester being 14.8% and 13.2% lower, respectively, than in the first trimester. Thyroid function parameters in the first trimester were similar to those measured after the end of pregnancy.ConclusionsThis study calculates trimester-specific RI for thyroid function parameters in pregnancy, and proposes the reference limits that should be adopted when using Roche platforms in Caucasian women.

The associations between concentrations of gestational bisphenol analogues and thyroid related hormones in cord blood: A prospective cohort study

Animal studies indicated that Bisphenol analogues (BPs) exhibited potential thyroid toxicity. However, little is known of the associations between maternal BPs exposure and offspring’s thyroid related hormones in humans. On the basis of Shanghai-Minhang Birth Cohort study, we analyzed BPs in maternal urine collected at the third trimester of pregnancy. Thyroid related hormones (THs), including total triiodothyronine (TT3), free triiodothyronine (FT3), total thyroxine (TT4), free thyroxine (FT4), and thyroid-stimulating hormone (TSH) were measured in cord blood samples. We performed multiple linear regression and Bayesian kernel machine regression (BKMR) models to explore the single and joint effects of gestational BPs exposure on thyroid related hormones in cord blood among 258 mother-child pairs. Statistically significant inverse associations of categorized BPA with FT3 and TT4 concentrations were observed. We also found a significant association between the mixture of BPs in maternal urine and increased concentration of TT3 in cord blood and a marginally significant association between BPs mixture and increased FT3 concentrations. Further associations of BPA with lower TT4/FT4 and of Bisphenol AF (BPAF) with higher TT3/FT3 were also suggestive, by BKMR model, when other BPs were fixed at 25th percentiles. It was concluded that prenatal BPs exposure was associated with THs in cord blood. Exposure to BPA and BPAF might have large contributions to the effects on thyroid function than other bisphenols.

Thyroid hormones in canine pregnancy and lactation

It is believed that thyroid function has a significant effect on fertility and fetal development in mammals. So far, however, only few studies have been published about potential effects of the reproductive cycle stage on thyroid hormone concentrations in dogs. Therefore, over the course of 122 pregnant and non-pregnant cycles in healthy bitches, Thyroid stimulating hormone (TSH), free Thyroxine (fT4), total Thyroxine (tT4) and Progesterone (P4) were measured six times to assess the influence of the cycle stage and pregnancy on hormone concentrations. The aim was to evaluate established reference intervals for the thyroid hormones in a female study population. Of the 122 bitches, 98 became pregnant. Blood samples were collected during estrus, three times in pregnancy, during lactation and after weaning, or at equivalent times during and after estrus in non-pregnant dogs. No differences between pregnant and non-pregnant animals in any of the thyroid hormones were found. Hormone concentrations, however, differed significantly between the six samplings (p < .01). TSH initially declined during pregnancy, then rose again. The mean concentration of all dogs exceeded the overall upper reference limit of 0.70 ng/mL during lactation. Concentrations of tT4 and ft4 increased during the first third of pregnancy and then subsequently declined. The overall reference limits for tT4 were 0.47–3.20 μg/dL, and for fT4 4.86–29.60 pmol/L, but the reference intervals varied between the sampling dates. The observed patterns may reflect that maternal tT4 and fT4 seem to have important effects during early pregnancy, including a pronounced negative feedback effect on TSH. The initial increase and subsequent decline of tT4 and fT4 concentrations during the course of pregnancy is in accordance with findings in humans and may support the development of fetal thyroid function. The observed peak of TSH concentrations during lactation suggests that the demand for thyroid hormones in this phase is largest. Even if the underlying causes and mechanisms of thyroid regulation are not fully understood, the results of this study show relevant changes of hormone concentrations in the course of the sexual cycle and pregnancy. In that regard, cycle stage needs to be considered when assessing thyroid function in bitches.

Association between thyroid hormones and diabetic kidney disease in Chinese adults

ObjectiveWe aimed to explore the association between thyroid hormones and different stages of diabetic kidney disease (DKD) in Chinese adults.MethodsThis is a retrospective study involving 2,832 participants. DKD was diagnosed and classified according to the Kidney Disease: Improving Global Outcomes (KDIGO) categories. Effect sizes are expressed as odds ratio (OR) with 95% confidence interval (CI).ResultsAfter propensity score matching (PSM) on age, gender, hypertension, hemoglobin A1c(HbA1c), total cholesterol (TC), serum triglyceride (TG) and duration of diabetes, per 0.2 pg/mL increment in serum free triiodothyronine (FT3) was significantly associated with 13%, 22% and 37% reduced risk of moderate-risk (OR, 95% CI, P: 0.87, 0.70–0.87, < 0.001), high-risk (0.78, 0.70–0.87, < 0.001) and very-high-risk (0.63, 0.55–0.72, < 0.001) DKD stages relative to the low-risk DKD stage, respectively. After PSM analyses, serum FT4 and TSH showed no statistical significance in risk estimates for all DKD stages. To facilitate clinical application, a nomogram prediction model was established for the moderate-risk, high-risk and very-high-risk DKD stages, with decent accuracy.ConclusionOur results indicate that high concentrations of serum FT3 were associated with the significantly reduced risk of having moderate-risk to very-high-risk DKD stages.

Fast Track Treatment of Hypothyroidism with Levothyroxine: Reaching Homeostasis within Four Weeks

With the current clinical method for the treatment of hypothyroidism the target for the optimum individual values for free thyroxine concentrations [FT4] and thyrotropine concentrations [TSH] of the specific patient are unknown. This situation leads to unnecessary long experimental medication administration that can take a period of sometimes one year. In this article a method will be described where hypothyroid patients are characterized with weekly measured FT4 and TSH concentrations during the first three weeks of synthetic thyroxine or levothyroxine (L-T4) treatment to predict their optimum [FT4] and belonging [TSH] endpoint for a euthyroid homeostatic state. The treatment with levothyroxine will start for all patients with a reference dose of 100µg, which can be adjusted by the treating physician to a more safe and appropriate dose for the individual which is monitored with weekly thyroid function tests to observe the progress. After three weeks all characteristics of the patient can be inferred from the measured data. Thefinal titration target together with the individual thyroxine half life can be calculated. With the known characteristics and the L-T4 titration target the clinician or treating physician has an instrument to reduce the experimental treatment burden for the patient from one year to a maximum of four weeks.

Thyroid evaluation in suspicious hypothyroid adult dogs before and after treatment.

The purpose of this study was to measure circulating TSH, T4 and fT4 concentrations in dogs submitted to a clinical visit for general symptoms (weight gain, polyuria and polydipsia, changes in hair coat). Twenty-eight dogs, 14 cross-breed and 14 purebreds (Golden Retriever, Labrador, Doberman), of both sexes (14 males and 14 females), aged 8 to 14 years, were assessed. No significant differences of circulating TSH, T4 , fT4 concentrations between the baseline and after therapeutic treatment nor between intact and neutered females were observed. Compared to baseline values, intact males showed higher TSH concentrations (p⟨0.01), and castrated males lower TSH concentrations (p⟨0.01) after therapeutic treatment. Compared to intact males, castrated males showed baseline TSH concentrations higher (p⟨0.01), but lower (p⟨0.01) after therapeutic treatment. No significant differences of T4 and fT4 concentrations between baseline conditions and after therapeutic treatment, nor between intact and castrated males, were observed. The experimental sample considered in this study falls within that casuistry involving elevated TSH concentrations but low serum T4 and fT4 concentrations or close to the minimum physiological cut-off, in which the common clinical signs suggestive of hypothyroidism was, essentially, overweight and neglected appearance of the hair.

Lower thyroid stimulating hormone concentrations linked to suicidal ideations among individuals with anxiety and mood disorders

IntroductionSuicidal behavior is quite common in individuals with anxiety and mood disorders (AMD). One of the coexistence factors in suicidal behavior is thyroid dysfunction, however the results are still controversial (Shen et al. J Affect Disord 2019;(1)180-185; Zhou et al., Transl Psychiatry. 2021;11(1):97). The role of thyroid function in suicidal ideation among individuals with comorbid AMD have not been thoroughly investigated.ObjectivesThe aim of this cross-sectional study was to identify potential associations between thyroid function and suicidal ideation in a sample of individuals with anxiety and mood disorders.MethodsThis exploratory study comprised 77 consecutive individuals with AMD (age range 18-73 years, 76% were females) attending the Psychiatry Day care unit. All individuals have been evaluated for current psychiatric diagnoses, suicidal ideation using the Mini International Neuropsychiatric Interview [M.I.N.I. 7.0.2]) as well as for socio-demographic factors and for current psychotropic medication use. Severity of depression and anxiety symptoms have been evaluated using the Patient Health Questionnaire-9 (PHQ-9) and the General Anxiety Disorder-7 (GAD-7). The biochemical blood tests were performed for the concentrations of thyroxine (FT4), triiodothyronine (FT3) and thyroid stimulating hormone (TSH). The univariate and multivariable logistic regression analyses were used to assess the association between biochemical parameters and suicidal ideation.ResultsOf all study individuals with AMD – 56% have been identified as having current SI. There were not significant differences according to age, gender, education, BMI, smoking, depression and anxiety symptoms and current psychotropics use between SI and non-SI individuals. Serum FT4, FT3 and TSH concentrations were within normal range. However individuals with SI had significantly lower TSH concentrations in comparison to the non-SI (1.54 (0.77) vs. 2.04 (1.22) IU/L, respectively; p = 0.049), without significantly differences in FT4 and FT3 concentrations. A multiple logistic regression, adjusting for sociodemographic factors and severity of mental symptoms revealed, that non-SI individuals with AMD were likely to have higher TSH levels than SI (odds ratio = 2.15 (95% CI 1.10–4.22; p = 0.027).ConclusionsAmong individuals with AMD, lower levels of TSH concentrations have been associated with presence of suicidal ideation, independently of sociodemographic factors and severity of depression and anxiety.Disclosure of InterestV. Liaugaudaitė Grant / Research support from: European Union (project No P-PD-22-150) under the agreement with the Research Council of Lithuania (LMTLT)., A. Podlipskytė: None Declared, J. Burkauskas Consultant of: Cronos, N. Mickuvienė: None Declared, V. Adomaitienė: None Declared, E. Zauka: None Declared, V. Steiblienė: None Declared

Thyroid Profile in the First Three Months after Starting Treatment in Children with Newly Diagnosed Cancer

Thyroid hormone anomalies during childhood might affect neurological development, school performance and quality of life, as well as daily energy, growth, body mass index and bone development. Thyroid dysfunction (hypo- or hyperthyroidism) may occur during childhood cancer treatment, although its prevalence is unknown. The thyroid profile may also change as a form of adaptation during illness, which is called euthyroid sick syndrome (ESS). In children with central hypothyroidism, a decline in FT4 of >20% has been shown to be clinically relevant. We aimed to quantify the percentage, severity and risk factors of a changing thyroid profile in the first three months of childhood cancer treatment. In 284 children with newly diagnosed cancer, a prospective evaluation of the thyroid profile was performed at diagnosis and three months after starting treatment. Subclinical hypothyroidism was found in 8.2% and 2.9% of children and subclinical hyperthyroidism in 3.6% and in 0.7% of children at diagnosis and after three months, respectively. ESS was present in 1.5% of children after three months. In 28% of children, FT4 concentration decreased by ≥20%. Children with cancer are at low risk of developing hypo- or hyperthyroidism in the first three months after starting treatment but may develop a significant decline in FT4 concentrations. Future studies are needed to investigate the clinical consequences thereof.

Increased fT4 concentrations in patients using levothyroxine without complete suppression of TSH.

In our hospital, physicians noticed high free thyroxine (fT4) concentrations without complete suppression of thyroid-stimulating hormone (TSH) in blood samples of patients at the outpatient clinic, which appeared to occur more often following the introduction of a new fT4 immunoassay. This discordance may be explained by incorrect reference intervals, analytical issues, or patient-related factors. We aimed to establish the contribution of the possible factors involved. Reference intervals of both fT4 immunoassays were re-evaluated using blood samples of healthy volunteers and the new immunoassay's performance was assessed using internal quality controls and external quality rounds. The frequency of discordant fT4 and TSH pairings obtained from laboratory requests were retrospectively analysed using a Delfia (n = 3174) and Cobas cohort (n = 3408). Last, a literature search assessed whether the time of blood draw and the time of levothyroxine (L-T4) ingestion may contribute to higher fT4 concentrations in L-T4 users. The original reference intervals of both fT4 immunoassays were confirmed and no evidence for analytical problems was found. The Delfia (n = 176, 5.5%) and Cobas cohorts (n = 295, 8.7%) showed comparable frequencies of discordance. Interestingly, 72-81% of the discordant results belonged to L-T4 users. Literature indicated the time of blood withdrawal of L-T4 users and, therefore, the time of L-T4 intake as possible explanations. High fT4 without suppressed TSH concentrations can mainly be explained by L-T4 intake. Physicians and laboratory specialists should be aware of this phenomenon to avoid questioning the assay's performance or unnecessarily adapting the L-T4 dose in patients.

Modeling the iron storage protein ferritin reveals how residual ferrihydrite iron determines initial ferritin iron sequestration kinetics.

Computational models can be created more efficiently by composing them from smaller, well-defined sub-models that represent specific cellular structures that appear often in different contexts. Cellular iron metabolism is a prime example of this as multiple cell types tend to rely on a similar set of components (proteins and regulatory mechanisms) to ensure iron balance. One recurrent component, ferritin, is the primary iron storage protein in mammalian cells and is necessary for cellular iron homeostasis. Its ability to sequester iron protects cells from rising concentrations of ferrous iron limiting oxidative cell damage. The focus of the present work is establishing a model that tractably represents the ferritin iron sequestration kinetics such that it can be incorporated into larger cell models, in addition to contributing to the understanding of general ferritin iron sequestration dynamics within cells. The model's parameter values were determined from published kinetic and binding experiments and the model was validated against independent data not used in its construction. Simulation results indicate that FT concentration is the most impactful on overall sequestration dynamics, while the FT iron saturation (number of iron atoms sequestered per FT cage) fine tunes the initial rates. Finally, because this model has a small number of reactions and species, was built to represent important details of FT kinetics, and has flexibility to include subtle changes in subunit composition, we propose it to be used as a building block in a variety of specific cell type models of iron metabolism.

Iodine Status in Pregnant Women Having Urinary Fluoride in Contaminated Areas: A Case Study of Phayao Province.

Fluoride naturally occurs in the Earth's crust and is widely dispersed in groundwater. The high consumption of fluoride can inhibit iodine metabolism in the human body, especially in the thyroid gland. This study assessed iodine knowledge, iodine consumption behavior, urinary iodine (UI), thyroid stimulating hormone (serum TSH), and free triiodothyronine3 (serum FT3) and examined the connection between fluoride exposure and UI and thyroid function as serum concentrations of TSH and FT3 in pregnant women dwelling in an area of endemic fluorosis. This was a cross-sectional study. The population included 152 pregnant women within the 1st trimester of pregnancy, during which they were provided antenatal care (ANC) in seven public community hospitals in Phayao province, Thailand. The study consisted of two components. First, the study consisted of a questionnaire in which we evaluated the iodine knowledge and iodine consumptive behaviors in subjects. Second, biochemical data were investigated to evaluate thyroid function in the subjects. The gestational age of most subjects was 8-12 weeks. The study population has lived in fluoride-contaminated areas since birth (76.97%). The iodine and iodine consumption levels were moderate (50.00%). Their food iodine consumption was 3-4 days/week, and the top five consumption ranks were iodized salt, cooked pork, eggs, sticky rice, and iodine fish sauce. In terms of biochemical parameters, 63.16% of respondents had UI levels below 150.00 g/L, which is below the normal reference range of 150.00-249.00 g/L. 89.47% of the risk of hypothyroidism was associated with serum TSH levels below 2.50 g/L. In 38.16% of the samples, normal levels of serum FT3 (2.00-4.40 pg/L) were identified in the subjects. In addition, 61.84% of the samples had FT3 concentrations greater than 4.40 pg/L (high intake of iodine). The approved association between positive serum FT3 data and serum TSH was positive (r = 260 and p < 0.05). These studies imply that these elevated levels of TSH and FT3 place pregnant women in their first trimester at risk for hypothyroidism.

P649 Does serum triiodothyronine-to-thyroxine (T3/T4) ratio predict therapeutic outcome to anti-TNF therapies in biologic-naïve patients with active luminal Crohn’s disease?

Abstract Background Lower serum free triiodothyronine-to-thyroxine (fT3/fT4) ratio has been linked to non-response to treatment in a range of diseases, including in biologic-treated patients with IBD. We sought to assess whether baseline serum fT3/fT4 ratio predicted primary non-response (PNR) and non-remission to infliximab and adalimumab in patients with Crohn’s disease. Methods We included 997 adult participants from the Personalised Anti-TNF Therapy in Crohn’s Disease study (PANTS). Thyroid function tests, using the Roche Elecsys TSH immunoassay and T3 and T4 electrochemiluminescence assays, were measured on stored baseline samples (prior to biologic treatment). PNR, assessed at week 14, was defined as treatment failure (including IBD-related surgery), ongoing corticosteroid use, or both CRP failing to fall to ≤3 mg/L, or by 50% from baseline, and HBI failing to fall to ≤4, or by 3 points. Non-remission, assessed at week 54, was defined as either CRP of &amp;gt; 3mg/L or HBI of &amp;gt;4 points, ongoing corticosteroid therapy, or exit for treatment failure. Results Serum fT3, fT4 and TSH concentrations were similar in infliximab (n=549) and adalimumab treated (n=448) patients. Baseline median [IQR] fT3/fT4 ratios were lower in women than men (0.30 [0.27 - 0.34] vs 0.32 [0.28 - 0.36], p&amp;lt;0.001), in patients with more severe inflammatory disease, and in patients receiving corticosteroids (0.28 [0.25 - 0.33] vs 0.32 [0.29 - 0.36], p&amp;lt;0.001). Multivariable logistic regression analysis demonstrated that fT3/fT4 ratio was independently associated with PNR at week 14 (OR 0.51, 95% CI 0.31 – 0.85, p = 0.009), however when stratified by drug and adjusted for variables known to be associated with PNR, low fT3/fT4 ratio remained associated with PNR for adalimumab, but not infliximab. After excluding patients treated with corticosteroids at baseline, there was no difference in fT3/fT4 ratio in those who experienced PNR compared to those who did not (PNR: [128/630] 0.31 [0.28 – 0.35] vs no PNR: [502/630] 0.32 [0.29 – 0.36], p = 0.095). The optimal threshold to determine PNR was 0.31 (AUC 0.57 [95% CI 0.54 - 0.61] sensitivity 0.62 [95% CI 0.41 - 0.74], specificity 0.53 [95% CI 0.42 - 0.73]). No association was seen for baseline fT3/fT4 ratio and non-remission or changes in faecal calprotectin concentrations at week 54. Conclusion Lower baseline serum fT3/fT4 ratio was independently associated with female sex, higher inflammatory burden at baseline, and baseline corticosteroid use, and predicted PNR to anti-TNF therapy at week 14, but not non-remission or change in faecal calprotectin concentrations at week 54. Overall, however, the diagnostic accuracy of baseline fT3/fT4 ratio to predict PNR to anti-TNF treatment was modest, limiting its clinical utility.

Evolution of non-thyroidal illness syndrome in acute decompensation of liver cirrhosis and acute-on-chronic liver failure.

Non-thyroidal illness syndrome (NTIS) is frequent in critically ill patients and associated with adverse outcomes. We aimed to characterize the evolution of NTIS in patients with acute decompensation (AD) of cirrhosis and acute-on-chronic liver failure (ACLF), since NTIS is not well described in these newly defined syndromes. Thyroid hormones (TH) were quantified at baseline in consecutive patients with cirrhosis. In addition, 76 inflammatory mediators were quantified by proximity extension analysis assay in a subgroup of patients. Associations between TH, cirrhosis stage, mortality and inflammation were assessed. Overall, 437 patients were included, of whom 165 (37.8%), 211 (48.3%), and 61 (14%) had compensated cirrhosis (CC), AD, and ACLF. FT3 concentrations were lower in AD versus CC, and further decreased in ACLF. Importantly, NTIS was present in 83 (39.3%) patients with AD and in 44 (72.1%) patients with ACLF (P<0.001). Yet, TSH and TSH-based indexes (TSH/FT3-ratio, thyroid index) showed an U-shaped evolution during progression of cirrhosis, suggesting a partially preserved responsiveness of the hypothalamus and pituitary in AD. Infections were associated with lower FT3 concentrations in AD, but not in ACLF. Low FT3 concentrations correlated significantly with 90-day mortality. Both, AD/ACLF and NTIS, were associated with signatures of inflammatory mediators, which were partially non-overlapping. NTIS is frequent already in AD and therefore precedes critically illness in a subgroup of patients with decompensated cirrhosis. This might constitute a new paradigm of TH signaling in cirrhosis, offering opportunities to explore preventive effects of TH in AD.

Low Free Triiodothyronine as a More Sensitive Predictor of Survival Than Total Testosterone among Dialysis Men.

Some endocrine disorders, previously considered benign, may be related to a poorer prognosis for patients with renal failure. Both low serum free triiodothyronine (fT3) and low total testosterone (TT) concentrations have been considered as predictors of death in dialysis patients, but the results of studies are inconsistent. In our study, we evaluated the relationships of the serum thyroid hormone levels and the total testosterone levels with survival in male dialysis patients. Forty-eight male dialysis patients, 31 on hemodialysis (HD) and 17 on peritoneal dialysis (PD), aged 61.4 ± 10.0, 59.2 ± 12.2 years, respectively, were included in the study. Serum thyroid hormones and total testosterone were measured. During the 12-month follow-up, nine all-cause deaths were recorded. The concentrations of fT3 were significantly lower in those who died than in the survivors (p = 0.001). We did not observe any statistically considerable differences between the group of men who died and the rest of the participants in terms of the total serum testosterone concentration (p = 0.350). Total testosterone positively correlated with fT3 (r = 0.463, p = 0.009) in the HD group. In the group of male dialysis patients, the serum concentration of fT3 had a better prognostic value in terms of survival than the total testosterone. A linear relationship between the fT3 levels and testosterone levels in men undergoing hemodialysis may confirm the hypothesis that some of the hormonal changes observed in chronic kidney disease (CKD) may have a common cause.

Association between prenatal androgens and cord blood androgens, a path analysis

To determine association paths between prenatal androgens and cord blood androgens. The concentrations of T, FT, DHT, DHEA and SHBG in prenatal venous blood and cord blood were measured in 342 pregnant women and their neonates. The association paths between these hormones in prenatal and cord blood were revealed using Pearson correlation, multiple linear regression and path analysis. CB-T, CB-FT and CB-DHT in male neonates were higher than those in female neonates. In male and female neonates, P-FT was lower than CB-FT; however, P-DHT and P-SHBG were higher than CB-DHT and CB-SHBG, respectively. P-DHEA was lower than CB-DHEA in female newborns. In male neonates, there were association paths of P-T → CB-T → CB-FT → CB-DHT, P-T → CB-FT → CB-DHT, P-T → P-FT → CB-FT → CB-DHT, P-T → P-DHT, CB-DHEA → CB-DHT, CB-DHEA → P-DHT, and CB-DHEA → P-DHEA. In female neonates, there were association paths of P-T → CB-T → CB-FT → CB-DHT, P-T → P-FT → CB-FT → CB-DHT, P-T → P-FT → P-DHT, P-T → P-DHT, P-DHEA → P-DHT, CB-DHEA → P-DHEA, and CB-DHEA → CB-FT. There were differences in the T, FT and DHT concentrations in cord blood between male and female neonates and in the FT, DHT, DHEA, and SHBG concentrations between prenatal and cord blood. P-T and P-FT concentrations were positively associated with CB-T and CB-FT concentrations, while CB-DHEA concentration was positively associated with P-DHEA concentration.

Hormonal variation and temporal dynamics of musth in Asian elephants (Elephas maximus) are associated with age, body condition and the social environment.

The sustainability of endangered Asian elephants in human care is threatened in part by low breeding success and concerns over individual animal wellbeing. Male elephants have received less research attention compared to females, yet males deserve special consideration due to their unique reproductive biology (particularly the sexual state of "musth") and the complex interaction of physiological, environmental, and social pressures they face. We measured fecal androgen metabolites (FAMs), fecal glucocorticoid metabolites (FGMs), and fecal triiodothyronine metabolites (FT3s) collected weekly over approximately 12months from 26 male Asian elephants housed in zoos across the US, hypothesizing that FAM, FGM, and FT3 concentrations would be associated with temporal correlates of musth and would vary further with intrinsic (musth status, age, body condition) and extrinsic (social environment) factors. The duration of each musth episode was positively associated with exposure to male conspecifics and negatively associated with body condition. Further, elevated FAM concentrations were associated with social exposure, age, and body condition, and FGM concentrations also varied with age and body condition. FT3 concentrations were not associated with any factor we measured. We also identified periods of lower FAM concentration than confirmed musth episodes (but still higher than baseline FAM concentrations) that we termed "elevated FAM episodes." The durations of these episodes were negatively correlated with exposure to other male elephants. Together, these results provide evidence that hormone profiles (including those that are predicted to change around musth) vary significantly between male Asian elephants in a way that may be attributed to intrinsic and extrinsic factors. Studies like these serve to enhance the sustainability of ex-situ populations by providing wildlife managers with information to enhance the health, welfare, and reproduction of threatened species like Asian elephants.

A cross-sectional study of lipid profile among school-going children with subclinical hypothyroidism in rural Telangana

Abstract Background: Subclinical hypothyroidism (SCH) is defined as serum thyroid-stimulating hormone (TSH) concentration above the statistically defined upper limit of the reference range and serum-free thyroxine (fT4) concentration within its reference range. The correlation of higher levels of TSH and dyslipidaemia in children is controversial. This study was done among school children to document the prevalence of SCH and to investigate the association between the lipid profile and TSH in children with SCH. Methods: A cross-sectional study among 982 school-going children (6-12 years) was conducted and 91 children with SCH were included. Their weight, height, body mass index (BMI), fasting lipid profile (serum total cholesterol [TC], triglycerides [TG] and high-density lipoprotein [HDL]) were converted to z scores and compared with the reference population data. Results: The prevalence of SCH was 11%. Mean TC, TG and HDL levels (mg/dL) were 169 ± 8.8, 66.4 ± 7.7 and 40.5 ± 4.1, respectively. The mean HDL value in the study population was significantly lower, whereas the mean TC levels were significantly higher than the population mean. There was no correlation between TC z scores and TSH (ρ = 0.071) and HDL z scores and TSH (ρ = −0.01371). Multiple linear regression showed a statistically significant association between TSH and HDL z scores (P = 0.006) and TSH and TC z scores (P = 0.008) after adjusting for age and BMI z scores. Conclusions: Children with SCH have an abnormal lipid profile. There is association between TSH and dyslipidaemia (decreased HDL and increased TC) in SCH.

Reference Intervals of Thyroid Hormones During Pregnancy Established by Three Statistical Methods.

Monitoring the thyroid hormones during pregnancy is of great importance for fetal growth and development. Throughout the whole pregnancy, there is constant fluctuation in the thyroid hormone reference intervals (RIs). The purpose of this study is to determine method- and trimester-specific RIs for thyroid-stimulating hormone, free thyroxine, and free triiodothyronine in pregnant women in China. In this study, 2,167 women with normal pregnancies (first trimester, n = 299; second trimester, n = 1,032; third trimester, n = 836) and 4,231 healthy nonpregnant women subjects were recruited. Serum thyroid-stimulating hormone (TSH), free thyroxine (fT4), and free triiodothyronine (fT3) concentrations were measured using electrochemiluminescence immunoassays in Abbott Alinity i analyzer. Following the exclusion of outliers, the RIs were determined using three statistical techniques: the non-parametric method, the Hoffmann method, and the Q-Q plot method. Pregnant women's levels of these three thyroid hormones differ markedly from those of healthy non-pregnant women. In addition, the concentrations of these three hormones change considerably over the course of the three phases of pregnancy. The Q-Q plot method offered more comparable RIs with the non-parametric method in healthy non-pregnant women than the Hoffmann method. Three statistical techniques were used to construct the trimester-specific RIs of thyroid hormones in pregnant women, and there was little difference between them all. The RIs by the non-parametric and Q-Q plot methods indicated closer RIs, and the RIs by the Hoffmann approach were higher and wider than those by the other two methods. For thyroid hormones, trimester-specific RIs are required. The RIs determined by non-parametric and Q⁃Q plot indirect calculation could be used as the alternative method.