Serum Free T4 Levels Research Articles

6430 SAT-534 Evaluating the Effectiveness of Combined T4 and T3 Therapy or Desiccated Thyroid Versus T4 Monotherapy in Hypothyroidism: A Systematic Review and Meta-Analysis

Abstract Disclosure: M. Nassar: None. A. Hassan: None. M.T. Desouki: None. S. Ramadan: None. M.A. Hassan: None. A. Chaudhuri: None. Background: Many patients with hypothyroidism experience persistent symptoms despite normalized TSH levels, which highlights the need for alternative treatment strategies. This study aims to evaluate the effectiveness of combined T4 and T3 therapy or desiccated thyroid (DTE) compared to T4 monotherapy, with a focus on thyroid profile, lipid profile, and quality of life metrics, including the 36-point thyroid symptom questionnaire (TSQ-36), Beck Depression Inventory (BDI) scores, and General Health Questionnaire (GHQ)-28 scores. Methods: A systematic literature search was conducted using a Boolean strategy on the following databases: Embase, Medline/PubMed, and Web of Science. The search included results from the inception of each database until 11/23/2023. We used the following keywords: "Armour Thyroid," OR "Thyroid Extract," OR "Natural Desiccated Thyroid," OR "Nature-Throid," "Desiccated Thyroid," OR "NP Thyroid," OR "Synthroid," OR "Levothyroxine," OR "Liothyronine," "Cytomel," OR "Thyroid USP," OR "Unithroid." AND "hypothyroidism. " We only included RCTs. We excluded non-English articles. Results: Initially, 6,394 records were identified. After removing 477 duplicate records, 5,917 records underwent title and abstract screening, excluding 5,874 records. The full texts of the remaining 43 articles were examined for eligibility, excluding 27 articles. Ultimately, 16 studies met the inclusion criteria and were incorporated into our analysis. We included two studies on desiccated thyroid and 15 studies on combined therapy. In this meta-analysis, combination therapy with T4+T3 revealed a significant reduction in free T4 levels (mean difference (MD): -0.34; 95% CI: -0.47, -0.20), total T4 levels (mean difference: -2.20; 95% CI: -3.03, -1.37), and GHQ-28 scores (MD: -2.89; 95% CI: -3.16, -2.63) compared to T4 monotherapy. Total T3 levels increased significantly in combined therapy (MD: 29.82; 95% CI: 22.40, 37.25). The analyses demonstrated moderate to high heterogeneity. There was no significant difference in heart rate, SHBG, TSH, lipid profile, TSQ-36, or BDI score. DTE significantly increased serum total T3 levels (MD: 50.90; 95% CI: 42.39, 59.42) and significantly decreased serum total T4 (MD: -3.11; 95% CI: -3.64, -2.58) and free T4 levels (MD: -0.50; 95% CI: -0.57, -0.43) compared to T4 monotherapy. Moreover, DTE treatment showed a modest increase in TSH levels (MD: 0.49; 95% CI: 0.17, 0.80). The analyses indicated low heterogeneity. There was no significant difference in heart rate, SHBG, lipid profile, TSQ-36, GHQ-28, or BDI score. Conclusions: Our study revealed that combined therapy and DTE lead to higher T3 and lower T4 levels compared to T4 monotherapy in hypothyroidism. However, no significant effects on heart rate, lipid profile, or quality of life were noted. Given the heterogeneity of results, personalized treatment approaches are recommended. Presentation: 6/1/2024

Thyrotoxic periodic paralysis - a retrospective study from Southern India.

Thyrotoxic periodic paralysis is a rare manifestation of thyrotoxicosis. Here, we describe the clinical and biochemical features and treatment outcomes of this disorder. This retrospective study was conducted at a tertiary care centre in southern India. The clinical and biochemical features, treatment received, and therapeutic outcomes of all patients with thyrotoxicosis and acute flaccid paralysis without any other identifiable causes (cases for the study) were compared with an equal number of consecutively selected patients who presented with thyrotoxicosis but without features of paralysis (controls for the study) during the same period. In total, 41 cases and controls were included in this study. The proportion of males was 92.6% and 43.9% in the cases and controls, respectively. The mean age was 32.8 (±7.6) years (cases) and 39.7 (±11.3) years (controls). In the cases, 20% of patients presented without clinical thyrotoxic features. Graves' disease was the most common aetiology of thyrotoxicosis in both groups (92.6% of cases and 87.8% of controls). The prevalence of goitre was significantly higher among controls (90.2%) than among cases (53.7%). The mean serum potassium, free T4, total T4 and total T3 levels were significantly lower in the cases than in the controls. In these cases, two patients had an additional aetiology for persistent hypokalaemia, likely Gitelman's syndrome. This is one of the largest series of thyrotoxic periodic paralysis cases in India. In subjects with thyrotoxicosis, serum potassium, free T4, total T4 and total T3 levels were significantly lower in those with periodic paralysis than in those without.

Evaluation of thyroid profile among children aged 1-15 years with nephrotic syndrome: An observation study.

The interaction between the kidney and the thyroid is important for normal function of both organs. In nephrotic syndrome, proteinuria leads to loss of several proteins, which in turn causes hypothyroidism. To assess the thyroid function in children with nephrotic syndrome. This cross-sectional study was conducted in a tertiary center, Bhopal, from February 2020 to January 2021. Consecutive children aged 1-15 years admitted with nephrotic syndrome (first-time diagnosed and all relapse cases) were included in the study. A thyroid profile was sent along with routine investigations, and thyroid hormone status was assessed in nephrotic syndrome children. Of the 70 patients, 39 (55.7%) showed abnormal thyroid profiles; 19 (27.1%) had overt hypothyroidism, and 20 (28.6%) had subclinical hypothyroidism. Overt hypothyroidism was seen in 16.1% of newly diagnosed cases, 40% of second relapses, and 2.7% of frequently relapsed cases (P < 0.001). The mean serum free T3 and free T4 levels in frequent relapses were 2.50 ± 0.39 ng/dL and 0.78 ± 0.12 ng/dL, respectively, which were significantly lower than in newly diagnosed cases (2.77 ± 0.37 ng/dL and 0.91 ± 0.19 ng/dL, respectively). The mean thyroid-stimulating hormone (TSH) level was significantly higher in frequent relapses 5.86 ± 1.56 µIU/mL) and second relapse (5.81 ± 1.78 µIU/mL) than in newly diagnosed cases (4.83 ± 0.76 µIU/mL) and first relapse cases (4.74 ± 1.17 µIU/mL), (P < 0.01). An abnormal thyroid profile was commonly observed in children with nephrotic syndrome, and overt hypothyroidism was more common in frequent relapse cases. Therefore, thyroid screening should be a part of the management of nephrotic syndrome so that hypothyroidism can be detected and managed at an early stage.

Interrelationship between thyroid hormones and reduced renal function, a review article

BackgroundUnderstanding the relationship of thyroid hormones with the development of chronic kidney disease (CKD) has important clinical implications for managing patients with both thyroid and kidney dysfunction. In this review, our purpose was to provide a thorough comprehension of the interplay between thyroid hormones, thyroid dysfunctions, and CKD.SummaryWhile there is evidence linking thyroid hormone levels to renal diseases, the association between thyroid hormones, specifically within the normal range, and the risk of CKD incidence is still a subject of debate. The Google Scholar, PubMed, Scopus, and Web of Science, were searched using the medical subject heading (MeSH) terms for the relevant keywords up to December 2023.ConclusionBased on the review, the development of CKD is more consistently associated with higher serum TSH and thereafter lower serum free T3 levels; however, its association with free T4 is more controversial. Furthermore, subclinical and overt hypothyroidisms were considerably associated with incident CKD. Hyperthyroidism and Hashimoto thyroiditis might increase the risk of CKD.

Low free T3 level may predict the severity of acute pancreatitis

ABSTRACT Objectives To demonstrate that deterioration in thyroid function tests can serve as an indicator of severity and prognosis in acute pancreatitis despite a healthy thyroid gland. Methods This study is a retrospective, single-center study. Patients diagnosed with acute pancreatitis between May 2020 and June 2021 were evaluated. Acute pancreatitis was diagnosed and classified according to the 2012 revised Atlanta criteria. Patients were categorized into Non-Thyroidal Illness Syndrome and euthyroid groups and compared in terms of biochemical parameters and scoring systems such as Ranson, Glasgow, Balthazar and BISAP scores. Results A total of 152 patients were included in the study. Eighty-three patients (54%) were euthyroid, with free triiodothyronine (T3), free thyroxine (T4), and Thyroid-stimulating hormone (TSH) levels within normal limits. Sixty-nine patients (46%) had Non-Thyroidal Illness Syndrome with low serum free T3 levels and low/normal TSH levels. As expected, free T3 was significantly lower in the Non-Thyroidal Illness Syndrome group than in the euthyroid group (1.5 ± 0.04 vs 2.6 ± 0.04, respectively, p < 0.0001). In the Non-Thyroidal Illness Syndrome group, Ranson score (3.35 ± 0.2 vs 2.11 ± 0.18 p < 0.0001), Glasgow (2.4 ± 0.2 vs 1.3 ± 0.1, p < 0.0001), Atlanta (p = 0.007), and Balthazar (2.1 ± 0.1 vs 1.4 ± 0.1, p = 0.001) scores were significantly higher than euthyroid group. Conclusion Non-Thyroidal Illness Syndrome provides insight into the prognosis of acute pancreatitis. Free T3 values are a significant parameter that may indicate the prognosis of acute pancreatitis. We believe that free T3 could be incorporated into an ideal scoring system in a disease such as acute pancreatitis, where early determination of prognosis is known to significantly reduce mortality.

Effect of progestin on thyroid function in female Wistar rats.

To characterize the influence of female-specific hormones on women's thyroid function, the study investigated the influence of extra progestin from oral contraceptives on inducing thyroid dysfunction. Sixty female Wistar rats were divided into six groups based on levonorgestrel or desogestrel administration as the main active agents: control, low (0.0039 mg*20-fold), medium (0.0039 mg*100-fold), high (0.0318 mg*100-fold) levonorgestrel (pure product); and low (0.0083 mg*20-fold) and high (0.0083 mg*100-fold) desogestrel (pure product). Progestin was administered by gavage every 4 days for 1 month. Statistical analysis was performed using one-way analysis of variance and the Kruskal-Wallis test. Following levonorgestrel gavage, serum free T4 and thyroidstimulating hormone levels were significantly lower in the experimental group than that in the control group (p=0.013 and 0.043). After desogestrel gavage, the serum free T4 and free T3 levels were lower in the experimental group than that in the control group (p=0.019 and 0.030). Thyroid hormone antibody concentrations were lower in rats administered levonorgestrel and desogestrel than that in control rats. Moreover, exposure to progestin upregulated the expression of the thyroid-stimulating hormone receptor and sodium iodide symporter in thyroid. Progestin stimulation enhanced the proliferation of follicular epithelial cells in rat thyroid tissues. Progestin exposure could cause thyroid dysfunction by upregulating the transcription of thyroid-stimulating hormone receptor and sodium iodide symporter in thyroid, thus inducing pathomorphological changes in rats' thyroid.

Association of Anxiety and Depressive Symptoms with Thyroid Hormone Concentrations in Patients with Primary Bone Tumors.

Timely identification and intervention of psychological disorders bear significant import in ameliorating the ensuing therapeutic trajectories in primary bone tumor patients. Moreover, perturbations in thyroxine and thyroid-stimulating hormone (TSH) levels have been linked to manifestations of depressive and anxiety-related symptoms. However, the precise interplay governing the nexus of anxiety, depression, and the levels of thyroxine and TSH within the context of primary bone tumor patients remains presently unexplored. The objective of this study is to investigate the potential correlation between the hypothalamus- pituitary-thyroxine (HPT) axis and the depressive as well as anxious states observed in patients afflicted with bone tumors. Patients with primary bone tumors were required to accept the assessments of anxiety and depressive symptoms as well as thyroid axis hormone concentrations. The depressive and anxiety symptoms were assessed using the Hamilton Depression Rating Scale (HAMD) and the Hamilton Anxiety Scale (HAMA) score. During each follow-up, peripheral venous blood samples were collected for subsequent analysis using radioimmunoassay methods to measure serum- free T3, free T4, and TSH levels, with the calculated free T3 to free T4 ratio indicating peripheral free T4 to free T3 conversion. Tests for trend were conducted to assess thyroid axis hormone concentrations, HAMA scores, and HAMD scores, while the correlation between HAMA or HAMD scores and thyroid axis hormone concentrations was examined through univariate regression analyses. The study included 30 primary bone tumor patients. Initial high HAMA and HAMD scores decreased over a year after surgery (P < 0.05), reflecting diminishing anxiety and depression. TSH levels reduced postoperatively, contrasting with increased free-T3 and free-T4 levels (p < 0.01). Multivariate analysis affirmed that positive correlations were noted between TSH and anxiety/depression scores, while free-T3 correlated negatively, adjusted for demographic factors (p < 0.05). No significant associations emerged between HAMA/HAMD scores and free-T4 or free-T3 to free-T4 ratio (p > 0.05). The early identification of the low T3 syndrome could prove instrumental in both intervening and preventing adverse emotional states associated with primary bone tumors.

Associations of TSH, free T3, free T4, and conversion ratio with incident hypertension: results from the prospective Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).

To evaluate the association of TSH, free T3 (FT3), free T4 (FT4), and conversion (FT3:FT4) ratio values with incident hypertension. The study included data from participants of the ELSA-Brasil study without baseline hypertension. Serum TSH, FT4 and FT3 levels, and FT3:FT4 ratio values were assessed at baseline, and incident hypertension (defined by blood pressure levels ≥ 140/90 mmHg) was estimated over a median of 8.2 years of follow-up. The risk of incident hypertension was evaluated considering a 1-unit increase in TSH, FT4, FT3, and conversion ratio values and after dividing these variables into quintiles for further analysis using Poisson regression with robust variance. The results are presented as relative risks (RR) and 95% confidence intervals (CIs) before and after adjustment for multiple variables. The primary analysis incorporated data from 5,915 euthyroid individuals, and the secondary analysis combined data from all euthyroid individuals, 587 individuals with subclinical hypothyroidism, and 31 individuals with subclinical hyperthyroidism. The rate of incident hypertension was 28% (95% CI: 27%-29.3%). The FT4 levels in the first quintile (0.18-1.06 ng/dL) were significantly associated with incident hypertension (RR: 1.03, 95% CI: 1.01-1.06) at follow-up. The association between FT4 levels in the first quintile and incident hypertension was also observed in the analysis of combined data from euthyroid individuals and participants with subclinical thyroid dysfunction (RR: 1.04, 95% CI: 1.01-1.07). The associations were predominantly observed with systolic blood pressure levels in euthyroid individuals. However, in the combined analysis incorporating euthyroid participants and individuals with subclinical thyroid dysfunction, the associations were more pronounced with diastolic blood pressure levels. Low FT4 levels may be a mild risk factor for incident hypertension in euthyroid individuals and persons with subclinical thyroid dysfunction.

Prevalence and feto-maternal outcomes of subclinical hypothyroidism in pregnancy among mothers attending a tertiary care hospital of Darjeeling District, West Bengal, India

Background: Pregnancy is a stressful test for the mother’s thyroid function. The frequency of hypothyroidism in pregnant women is high. However, there are no adequate studies to evaluate the adverse effects of subclinical hypothyroidism (SCH) during pregnancy. Aims and Objectives: This study was carried out to evaluate the prevalence of SCH in pregnancy and its adverse feto-maternal outcomes among mothers attending a tertiary care teaching hospital in Darjeeling district, West Bengal, India. Materials and Methods: The present study was an institution-based observational descriptive study with a prospective longitudinal design conducted for 1 year among pregnant women attending the antenatal clinic of the study institution in the first trimester of their pregnancy. The sample size for the present study was calculated to be 200. A consecutive sampling technique was utilized. The enrolled women were evaluated for thyroid status by assessing serum thyroid stimulating hormone and free T4 level. All the enrolled mothers were kept under close follow-up and they were evaluated for the development of any antenatal, intranatal, and postnatal complications. Results: The mean age was found to be 23.1±4.2 years, most of the women were nulliparous (60%). Of the women, 74% were euthyroid, while the prevalence of SCH was found to be 16%. On follow-up till the termination of their pregnancies, mothers suffering from SCH had statistically significantly higher incidence of maternal complications such as hypertensive disorders in pregnancy (P=0.001), abortion (P&lt;0.001), postpartum hemorrhage (P=0.020) and also fetal adverse outcomes, such as intrauterine growth restriction (P=0.018), fetal premature birth (P=0.035), and low birth weight (P=0.004) when compared with euthyroid mothers. Conclusion: The burden of SCH high in the study population, and it was significantly associated with a number of different maternal as well as fetal complications and adverse outcomes.

Expression of hTERT and Lp-PLA(2) genes is increased in primary hypothyroidism.

ObjectiveSightly low serum free T4 levels are associated with longer life expectancy. However, hypothyroidism is associated with increased risk of inflammation and vascular complications. Therefore, relation of thyroid hormones (THs) with life expectancy seems to be complex. This study was carried out in an effort to understand the contribution of THs in inflammation and aging. Methodology15 cases of treatment naïve primary hypothyroidism and 15 age and sex matched euthyroid controls were recruited. mRNA expression of Telomerase (hTERT), leucocyte telomere length (LTL) and Lipoprotein associated phospholipase A2 (Lp-PLA2), a marker of vascular inflammation and risk predictor of cardiovascular events were measured by qPCR in whole blood. ResultExpression of hTERT was found to be 6.95 times higher in the cases as compared to the controls. mRNA expression of Lp-PLA(2) was also 3.3 times higher in cases. LTL in euthyroid was approximately 81% of the length in hypothyroid patients. ConclusionA higher expression of hTERT indicates that hypothyroidism confers better cell survival in peripheral leucocytes inspite of the presence of vascular inflammation. However causal relationship cannot be ascertained with these results.

Thyroid Hormone Homeostasis in Levothyroxine-treated Patients: Findings From ELSA-Brasil.

The effectiveness of levothyroxine (LT4) in restoring thyroid hormone (TH) homeostasis, particularly serum thyroxine (T4) and triiodothyronine (T3) levels, remains debatable. This work aimed to assess TH homeostasis in LT4-treated individuals using data from the Longitudinal Study of Adult Health in Brazil (ELSA-Brasil) study. The ELSA-Brasil study follows 15 105 adult Brazilians (aged 35-74 years) over 8.2 years (2008-2019) with 3 observation points assessing health parameters including serum thyrotropin (TSH), free T4 (FT4), and free T3 (FT3) levels. We analyzed 186 participants that initiated treatment with LT4 during the study, and 243 individuals continuously treated with LT4 therapy. Initiation of therapy with LT4 resulted in an 11% to 19% decrease in TSH, an approximately 19% increase in FT4, and a 7% reduction in FT3 serum levels (FT3 dropped >10% in ∼40% of the LT4-treated patients). This was associated with an increase in triglyceride levels and utilization of hypolipidemic and antidiabetic medications. Participants continuously treated with LT4 exhibited a stable elevation in serum FT4 and a reduction in serum FT3 and TSH levels. While 115 participants (47.3%) had at least 1 serum FT4 levels above the control reference range (>1.52 ng/dL), 38 participants (15.6%) had at least 1 serum FT3 below the reference range (<0.23 ng/dL). The present results challenge the dogma that treatment with LT4 for hypothyroidism restores TH homeostasis in all patients. A substantial number of LT4-treated patients exhibit repeated FT4 and FT3 levels outside the normal reference range, despite normal TSH levels. Further studies are needed to define the clinical implications of these findings.

Clinicopathological Evaluation of Papillary Thyroid Microcarcinoma.

Clinicians sometimes encounter papillary thyroid microcarcinoma (PMC) that is less than 10 mm, associated with lymph node metastasis. In this study, we assessed PMC clinicopathologically to clarify risk factors for poor prognosis. Fifty-one patients who underwent thyroid surgery at Aichi Medical University from September 2009 to October 2016 were included. Patients were divided into two groups, pEX-positive (23 patients) and pEX-negative (28 patients), based on the pathological finding of thyroid capsule invasion. The former indicates that the tumor infiltrated the thyroid capsule and spreadto the neighboring tissue, and the latter indicates no capsule invasion. We analyzed factors such as patient characteristics, pathological findings, and serum levels of thyroid hormones in the two groups. No statistical differences were observed between the two groups in gender distribution or age at surgery. Preoperative cancer diagnoses were established for more patients in the pEX-positive group than in the pEX-negative group (n = 21 and 14, respectively; P = 0.004). The mean (±SD) pathological tumor diameter was 5.42 ± 2.77 in the pEX-negative group and 8.32 ± 1.61 in the pEX-positive group (P < 0.001). No significant differences in preoperative serum levels of free T3, free T4, thyroid-stimulating hormone, or thyroglobulin were observed between the two groups. The odds ratio for node positivity in tumors invading thyroid capsules (pEX-positive) compared to those with no capsule invasion (pEX-negative) was 13.20 (95% confidence interval, 3.45-50.42). Immunohistological staining for phosphatase and tensin homolog deleted from chromosome 10 (PTEN) and Akt (protein kinase B) revealed the facilitation of PTEN and suppression of Akt, which might indicate downregulation of the phosphoinositide 3-kinase-Akt (PI3K-Akt) cascade. In general, the prognosis of PMC is favorable. However, the prognosis is less favorable in patients with nodal metastasis or extrathyroidal invasion. It is controversial whether resection is required for proven PMCs. For PMCs associated with extrathyroidal invasion, regional lymph node resection with lobectomy should be performed due to the high risk for lymphatic spread. There might be a possibility that the natural progression of PMC seems to be controlled by the facilitation of PTEN. However, a tumor in the lateral peripheral region of the thyroid parenchyma might be associated with capsule invasion followed by lymphatic spread.

Approach to management of hypo and hyperthyroidism in Bangladesh: a nationwide physicians' perspective survey.

Thyroid disorders are common clinical conditions globally. The objective of the present study was to evaluate the physicians' approach to the diagnosis and treatment of thyroid disorders in Bangladesh. The present nationally representative cross-sectional study was conducted among 662 physicians of different levels (general practitioners as well as specialists) from different hospitals in Bangladesh from January to June 2023. A self-administered semi-structured questionnaire including information about demographics and practice patterns for the diagnosis and management of thyroid disorders was used for data collection. Descriptive statistics were used to analyze the data. The American Thyroid Association (ATA) guidelines were the most commonly followed guidelines for the diagnosis and management of thyroid disorders (60%), followed by the American Association of Clinical Endocrinologists (AACE) guidelines (18%) and the European Thyroid Association (ETA) guidelines (9%). Serum TSH, free T3 and free T4 levels were the most frequently used diagnostic tests for the evaluation and follow-ups of both hypothyroid and hyperthyroid states in adults, pregnant women and children, followed by total T3 and total T4 levels. Other tests, such as anti-TPO antibody, anti-TG antibody, anti-TPO, ultrasound scan of the thyroid gland, etc., were rarely used by the participating physicians. Levothyroxine at a dose of 25 to 50 mcg and carbimazole at a dose of 30 to 45 mg were the most frequently used drugs for hypothyroid and hyperthyroid patients, respectively. Almost 65% of the physicians suggested routine thyroid function tests before surgery. In addition, more than 90% of the physicians agreed that thyroid screening for pregnancy, neonates, school children and adults would be mandatory. The majority of the physicians participating in our study followed relevant guidelines for the diagnosis and management of thyroid disorders in Bangladesh. However, there are still some gaps to be improved, as a good number of physicians did not follow specific guidelines for these disorders.

Brainstem auditory evoked responses in newly diagnosed untreated hypothyroid females

Background: Hypothyroidism stands as a prevalent endocrine disorder, affecting females more than males. Among the array of otolaryngological manifestations linked with thyroid dysfunctions, sensorineural hearing loss emerges as the most frequently encountered issue. Evoked potentials serve as valuable tools extensively utilized in studying brain disturbances. Among these evoked potentials, Brainstem Auditory Evoked Response (BAER) stands out as one of the methods employed for assessing the pathology within the brainstem auditory pathway. Aims and Objectives: The aim of the study is to evaluate the auditory sensory process in the brainstem using BAERs in newly diagnosed untreated hypothyroid individuals. Materials and Methods: Forty newly diagnosed untreated hypothyroid females of 20–50 years were taken as cases and forty age-matched females were considered controls. The hypothyroidism was diagnosed by estimating the serum levels of free T3 (fT3), free T4 (fT4), and thyroid-stimulating hormone. After getting informed written consent, the absolute latencies and interpeak latencies of BAER were recorded using NeuroPerfect EMG 2000 system with installed BAER in the research laboratory, Department of Physiology, Coimbatore Medical College, Coimbatore, and the data were analyzed by student unpaired t-test. Results: The absolute latencies I, III, V and interpeak latencies I- III, III- V, I – V were significantly prolonged in newly diagnosed untreated hypothyroid females (P &lt; 0.0001) and also there was a direct correlation between thyroid profile changes and the BAER latencies. Conclusion: The results of the present study suggest that hypothyroidism impacts the auditory pathway diffusely and early identification of auditory pathway involvement in thyroid hormone deficiency can be achieved using BAER. Prolonged BAER latencies observed in newly diagnosed untreated hypothyroid females are attributed to defective myelination of neural pathways and diminished cerebral metabolism. Hence, integrating BAER recordings into screening protocols could enhance the accuracy and early assessment of neurological involvement in hypothyroid females.

Study of Feto-Maternal Outcome in Pregnancy with Subclinical Hypothyroidism

Background: Hypothyroidism has a great impact on pregnancy. But there is a controversy about the maternal and perinatal outcomes of subclinical hypothyroidism (SCH). This study was placed to know the significant effects. Methods and Materials: A descriptive longitudinal study was held in Z. H. Sikder Women’s Medical College &amp; Hospital, Dhaka, Bangladesh. 400 pregnant women were included in this study with purposive sampling. All antenatal patients from booking visit at 1st trimester to delivery were monitored by serum TSH and serum FT4 levels in each trimester and fetal outcomes were also monitored. 200 pregnant women were diagnosed as subclinical hypothyroidism (SCH) with random screening of initial thyroid function tests. Another 200 pregnant women were euthyroid. The study period was 3 years, from January 2020 to December 2022. To evaluate the thyroid status, maternal serum samples were collected in each trimester, total three times. Maternal outcomes, which we studied, were gestational hypertension, gestational diabetes mellitus, maternal anemia, antepartum hemorrhage, postpartum hemorrhage, placental abruption, preterm delivery, premature rupture of membranes (PROM), caesarean deliveries; perinatal outcomes were low birth weight (LBW), intrauterine growth restriction (IUGR), low Apgar score, stillbirth, congenital anomaly and NICU admission. Result: This study includes 400 pregnant women, among which 200 were euthyroid and 200 were with SCH. The mean age was 27.12 ± 0.05 years in pregnancy with euthyroid group and 26.31 ± 0.25 in pregnancy with SCH group. Among the pregnancy with euthyroid group, 141 women were nullipara and 59 women were nullipara. Among the pregnancy with SCH group, 87 women were nullipara and 113 women were nullipara. Serum TSH level was 4.44 ± 0.11 in 1st trimester, 4.74 ± 0.19 in 2nd trimester, 5.45 ± 0.17 in 3rd trimester. Serum free T4 level was 8.29 ± 0.13 in 1st trimester, 6.65 ± 0.15 in 2nd trimester, 6.67 ± 0.34 in 3rd trimester. In pregnancy with SCH group gestational hypertension, miscarriage, placental abruption and premature rupture of membranes (PROM) were significantly higher (p&lt;0.001). Antepartum hemorrhage (APH), preterm delivery and Caesarian deliveries were also higher in this group (p&lt;0.05). Among the neonatal outcomes, low birth weight and intrauterine growth restriction (IUGR) babies were more born in pregnancy with SCH group. Anti TPO antibody titer was significantly higher in pregnant women with SCH. Conclusion: Subclinical hypothyroidism (SCH) is associated with increased risk of gestational hypertension, premature rupture of membranes (PROM), abruptio placentae and fetuses have more risk of IUGR and LBW. Therefore, routine maternal thyroid function test should be done to protect from adverse maternal and fetal outcome.

Frequency of Subclinical Hypothyroidsim Among Patients with end Stage Renal Disease on Hemodialysis Presenting to A Tertiary Care Hospital

Objective: Aim of this study was to determine the frequency of subclinical hypothyroidism among patients with end stage renal disease presenting to tertiary care hospital.&#x0D; Study Design: Cross sectional study.&#x0D; Place and Duration of Study: Department of Nephrology, Sharif Medical City Hospital, Lahore. Pakistan, from Mar 2020 toDec 2020.&#x0D; Methodology: A total of 200 cases studied. Informed consent was obtained from them. Data was noted in the proforma. Using aseptic techniques blood sample was taken for testing serum TSH and free T4 levels through radioimmunoassay. Results were collected by the researcher next day and were labeled and noted as subclinical hypothyroidism according to its clinical definition. Privacy of the data was maintained.&#x0D; Results: In 200 study cases age interval was 15-80 years with mean age of 46.22±19.67 years. The minimum Serum TSH level was 4.1 and maximum was 4.6 with mean serum TSH level was 4.31±0.16. The minimum Serum T4 levels was 0.5 and maximum was 2.1 with mean Serum T4 levels was 1.28±0.68. Duration of chronic kidney disease was 3-60 months with mean duration of 17.58±14.14 months. It was observed that there were 56.5% male patients while females were 43.5%. Subclinical Hypothyroidism was present in 9.5% patients with ESRD reporting to tertiary care hospital while it was absent in 90.5% patients. &#x0D; Conclusion: The frequency of subclinical hypothyroidism was found as 9.5% among patients with end stage renal disease presenting to tertiary care hospital.

FRI471 Regulation Of Adult Thyroid Hormone Homeostasis By Early Postnatal Hyperthyroidism In Male Mice

Abstract Disclosure: D. Kovári: None. A. Szilvásy-Szabó: None. V. Penksza: None. B. Gereben: None. C. Fekete: None. The thyroid hormone (TH) negative feedback regulation enables the hypothalamic-pituitary-thyroid (HPT) axis to maintain the relatively steady circulating TH levels. Internal and external factors influence the development of this feedback regulation and consequently evoke life-long changes of the HPT axis activity. The aim of our study was to reveal how perinatal alteration of TH status influences TH homeostasis of adult mice. Mice were treated with 1µg/bwg thyroxine (T4) or vehicle subcutaneously every day between postnatal day (P) 2-6 and sacrificed at adulthood. Early postnatal hyperthyroidism resulted in central hypothyroidism in adults, characterized by decreased thyrotropin releasing hormone (TRH) mRNA expression in the hypothalamic paraventricular nucleus (PVN) and lower serum free T4 level, accompanied by unchanged thyrotropin stimulating hormone β (TSHβ) mRNA expression in the pituitary and serum free triiodothyronine level. The two main regulators of the HPT axis are the hypophysiotropic TRH neurons and tanycytes. Tanycytes affect the feedback regulation of TRH neurons by type 2 deiodinase (D2) mediated TH activation. To understand how postnatal T4 treatment results in central hypothyroidism in adult mice, tanycytes and TRH neurons of the PVN were isolated by laser capture microdissection from control and postnatally T4 treated adult mice. Postnatal T4 treatment did not change D2 expression in the tanycytes. Furthermore, using Thyroid Hormone Action Indicator (THAI) mice, we showed that the treatment did not influence TH action in the mediobasal hypothalamus of adult mice. These data together indicate that tanycytes are not involved in mediation of the postnatal T4 treatment induced effects. In contrast, the early postnatal T4 treatment markedly changed the transcriptome of TRH neurons in the PVN of adult mice. The expression of TH receptors, most TH receptor-related coregulators, TH transporters and genes involved in the synthesis of TRH were decreased. Despite of the central hypothyroidism, the energy expenditure of these mice were not decreased and TH action also remained unchanged in most tissues indicating that the peripheral tissues are able to compensate the effect of the generated mild hypothyroidism. These results indicate that alteration of TH levels during the early postnatal period can cause life-long effects on the activity of the HPT-axis likely via epigenetic regulation of TRH neurons. Presentation: Friday, June 16, 2023

Normal intellectual ability and hyperprolactinemia as unique clinical manifestations of congenital hypothyroidism: A case report and review of hypotheses.

Congenital hypothyroidism is the deficiency of thyroid hormone in infants and hyperprolactinemia is frequently observed. Previously reported cases typically involve intellectual disability, highlighting this particular unique case report to the first reported patient demonstrating normal intellectual ability despite experiencing growth and gonad dysfunction. This study aims to present a case and review medical hypotheses related to the patient's condition. A 19-year-old female presented with a chief complaint of irregular menstruation for up to 40 days or not occurring at all. The patient experienced the first menstruation at the age of 16 years old. The patient's height was 133 cm, body weight 40 kg, and body mass index 22.61 kg/m2; other family members were normal. Physical examination showed no abnormalities, and laboratory examination showed suppressed serum free T4 (FT4) level (6.41 pmol/L), elevated thyroid stimulating hormone (TSH) level (333.700 µIU/mL), and elevated prolactin hormone level (32.03 ng/mL). Ultrasound of the thyroid gland found hypoplasia of the left and right thyroid glands. The patient was a college student enrolled in a public national university and had never complained about academic performance throughout the patient's education. The patient was diagnosed with congenital hypothyroidism and hyperprolactinemia. The patient was administered up to 100 µg daily of oral levothyroxine, which improved the patient's menstrual cycles. The patient's delayed diagnosis may be attributed to central congenital hypothyroidism being underdiagnosed. We hypothesized that thyroid-releasing hormone receptor (TRHR) gene mutation might contribute to the underlying cause of hyperprolactinemia and normal intellectual ability of the patient. Further study on the significance of TRHR gene mutations in congenital hypothyroidism is required to improve diagnosis and treatment.

Assessment Of The Effect Of Menopause On Thyroid Function In South East,Nigeria

Menopause marks the end of a woman’s reproductive life and is associated with significant physiological changes. The thyroid gland plays an important role in regulating overall body metabolism including sexual development and reproductive function. Worldwide, thyroid gland diseases are among the most common endocrine disorders in females, especially those in menopause. This study evaluated the effect of menopause on thyroid function. Methodology: It was a case-control study among post-menopausal women in Nnewi, Anambra, Nigeria with pre-menopausal women serving as controls. Sampling was by simple random method and comprised 45 post-menopausal women matched with 45 premenopausal women in a ratio of 1:1. Data was obtained with the use of a semi-structured questionnaire. The subjects’ blood samples were taken and assayed for thyroid stimulating hormone (TSH), thyroxine (T4), and triiodothyronine (T3) by ELISA technique. Their body mass index (BMI) and blood pressure were obtained using standard procedures. Result: The mean serum levels of free T4 and TSH in the menopausal individuals were significantly higher compared to the premenopausal group. Following linear regression analyses with adjustment for age and BMI, the the average level of TSH and free T4 were higher in the study group, while free T3 level was lower. Also, systolic and diastolic blood pressure was significantly higher in the study group than in the control group. Conclusion: The findings suggest that menopause is associated with reduced thyroid function and could as a result play a role in cardiovascular disease play a role in cardiovascular dysfunction among women

Thyroid function and thyroid autoimmunity in type 1 diabetes mellitus: impact on glycemic control

Background: The frequency of AITD (autoimmune thyroid disease) and prevalence of thyroid autoantibodies in T1DM (Type 1 diabetes mellitus) patients is much higher than in general paediatric population, varying widely between 3-50% and is often related to age, gender and ethnicity. Although this association has been well established in various populations, very few studies have been done in this regard in South India. The objectives of the study were to study the proportion of abnormal thyroid function and thyroid autoimmunity among T1DM subjects in comparison with general pediatric population and to compare the disease severity among T1DM subjects with and without abnormal thyroid function. Methods: The 45 subjects diagnosed with T1DM (Group 1) and 45 age and gender matched subjects without T1DM (Group 2) were enrolled after applying the inclusion and exclusion criteria. Serum free T3, free T4 and TSH levels were tested for all the subjects in both the groups. In addition, HbA1c levels and Anti TPO antibody titers were tested for subjects with T1DM. Results: Abnormal thyroid function was found in 15.5% of T1DM subjects, in contrast to 2.2% of subjects in the comparison group (p=0.026). The anti-TPO antibody titers were positive in 31.1% of T1DM subjects and among them 42.8% subjects had abnormal thyroid function. T1DM subjects with abnormal thyroid function had significantly higher number of hospitalizations (p&lt;0.05) and total number of ICU admissions (p&lt;0.05) Conclusions: Abnormal thyroid function (predominantly subclinical hypothyroidism) and thyroid autoimmunity was not only more prevalent among T1DM subjects, but was also associated with poor glycemic control. Thus, highlighting the need for screening and a lower threshold for treatment.