Subclinical Hypothyroidism Group Research Articles

Features of atherosclerotic lesions of the coronary arteries in patients with myocardial infarction and concomitant newly diagnosed hypothyroidism

Objective: to assess the incidence of newly diagnosed subclinical and manifest hypothyroidism in patients with ST-segment elevation myocardial infarction (STEMI) and to identify angiographic features of coronary artery lesions in this combined pathology.Materials and methods: in all patients with STEMI, the level of thyroid-stimulating hormone (TSH) was determined, and thyroid function was assessed if the TSH level deviated from the norm. Stage I of the study included 441 patients, stage II included 133 patients with STEMI. Depending on the presence of newly diagnosed hypothyroidism, patients were divided into 3 groups: 1st — patients without hypothyroidism (n = 57), 2A group — with subclinical hypothyroidism (n = 42) and 2B group — with manifest hypothyroidism (n = 34). All patients underwent coronary angiography and percutaneous coronary intervention.Results: newly diagnosed hypothyroidism occurred in 27.44% of patients with STEMI: subclinical — in 19.73%, manifest — in 7.7% of cases. Patients with concomitant overt hypothyroidism had significantly more severe atherosclerotic lesions of the coronary arteries compared to patients without hypothyroidism.Conclusion: a high incidence of newly diagnosed hypothyroidism in patients with STEMI was established (27.44% of cases). Multivessel coronary lesions were recorded more often in patients with overt hypothyroidism than in patients with subclinical hypothyroidism and without hypothyroidism.

Association between Subclinical Hypothyroidism and Adverse Pregnancy Outcomes in Assisted Reproduction Technology Singleton Pregnancies: A Retrospective Study.

Background/Objectives: Women with subclinical hypothyroidism (SCH) were reported to be at an increased perinatal risk. We aimed to investigate the relationship between SCH and perinatal outcomes in singleton pregnancies resulting from assisted reproduction technology (ART). Methods: We retrospectively examined the perinatal outcomes of ART singleton pregnancies in women who underwent thyroid function screening before conception and delivered at our hospital from January 2020 to July 2023. We defined SCH as thyroid-stimulating hormone (TSH) levels > 2.5 mU/L and normal free T4 levels. The patients were categorized into three groups: normal thyroid function (group A), SCH without levothyroxine therapy (group B), and SCH with levothyroxine therapy (group C). The risks of preterm birth, preeclampsia, fetal growth restriction, manual placental removal, and blood loss at delivery were compared among the three groups. Results: Out of the 650 ART singleton deliveries, 581 were assigned to group A, 34 to group B, and 35 to group C. The preterm birth rate at <34 weeks was significantly higher in group B and significantly lower in group C than in group A. The rate of preterm delivery at <34 weeks increased in correlation with TSH levels. Levothyroxine therapy was the significant preventive factor for preterm birth at <34 weeks. Conclusions: The preterm birth rate before 34 weeks was significantly higher in the SCH group. Levothyroxine therapy is a significant protective factor against preterm birth before 34 weeks. Universal screening for thyroid function and appropriate hormone therapy in pregnant women may help reduce perinatal risks, including preterm birth.

A Cross-Sectional Study on the Prevalence of Subclinical Hypothyroidism in Metabolic Syndrome Patients at a Tertiary Care Hospital.

Metabolic syndrome (MetS) is defined as a "constellation" of cardiometabolic risk factors, characterized by hypertension, atherogenic dyslipidemia, hyperglycemia, prothrombotic and proinflammatory conditions which, jointly, increase the risk of suffering cardiovascular diseases (CVD) and type 2 diabetes mellitus.Thyroid dysfunction is also believed to affect parameters such as high-density lipoprotein (HDL) cholesterol, triglycerides, plasma glucose, and blood pressure, in turn increasing the risk of CVD. Subclinical hypothyroidism (SCH), which independently raises the risk of CVDs and their associated complications, is more frequently detected in patients with MetS compared to the general population. When both conditions coexist, the risk of CVD and its complications is significantly heightened. The objective of the study was to find out the prevalence of SCH in patients with MetS. A prospective cross-sectional study was conducted in the Department of General Medicine, New Civil Hospital, Surat, Gujarat, India. Eighty patients who fulfilled the criteria for MetS by the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III), were taken into the study. A detailed history, anthropometric measurements, blood pressure, fasting blood glucose, lipid profile, and thyroid profile (Free T3, Free T4, and serum thyroid-stimulating hormone (TSH)) were undertaken. The thyroid profile was done by chemiluminescence immunoassay (CLIA) method. Out of 80 patients with MetS, 48 were female and 32 were male, with the overall mean age of the study population being 46.5±9.5 years. Among them, 23.7% of the population was found to be having thyroid dysfunction. Among the thyroid dysfunction, SCH was highly prevalent (18.8%), 3.8% patients had overt hypothyroidism and 1.3% patients had subclinical hyperthyroidism. There were no overt hyperthyroid patients in our study.HDL (mg/dl) and TSH (mIU/L) were significantly higher in the SCH group as compared to other types of hypothyroidism group (p-value < 0.05). There is a statistically significant prevalence of SCH (18.8%) in MetS patients. It is clear from the study that one-fifth of MetS patients or every fifth patient with MetS had SCH. Thus, looking proactively for SCH in MetS and treating it would prevent conversion to overt hypothyroidism and complications of MetS.

Pregnancy outcome in subclinical hypothyroidism with and without thyroid peroxidase antibodies-a prospective cohort study.

Subclinical hypothyroidism (SCH) in pregnancy is associated with adverse foetomaternal outcomes. The literature is scarce with respect to maternal and perinatal outcomes in women with mild SCH (TSH levels between 2.5-4 mIU/L). The primary objective of the study was to compare the pregnancy outcome between SCH and euthyroid women. The secondary objectives were to find out the proportion of women with SCH having thyroid peroxidase antibodies (TPOAb) and to see the effect of TPOAb positivity on foetomaternal outcomes. A total of 178 pregnant women were recruited in the first trimester, and those with TSH between 0.1 and 2.4 mIU/L were considered as euthyroid and 2.5-4mIU/L were labelled as SCH. Women with SCH underwent testing for TPOAb. All women were followed until delivery, and foetomaternal outcomes were assessed. Amongst SCH group, there was a significantly higher proportion of overweight and obese women (76/91 (83.51%) vs 59/87 (68%), p = 0.031). The neonatal intensive care unit (NICU) admission was higher with adjusted odds ratio of 3.24 (1.41-7.43) in women with SCH as compared to euthyroid women. Otherwise, there was no difference in foetomaternal outcomes between the two groups. The proportion of gestational diabetes mellitus, intrauterine growth retardation and still birth were higher in SCH women with TPOAb as compared to euthyroid. Amongst SCH women, the proportion of induced labour was lower (aOR:0.27 (0.08-0.93) whereas the proportion of stillbirth and low APGAR scores were higher in TPOAb-positive women with a statistically significant difference and adjusted odds ratio (aOR:20.18 (1.84-220.83)) and (aOR:4.77 (1.06-21.3)), respectively, when compared to TPOAb-negative women. There appears to be no difference in pregnancy outcomes between women with SCH and euthyroid women except higher NICU admission in SCH group. Future multi-centre large prospective studies are required to understand better about the pregnancy outcomes in these women.

Association of maternal mild hypothyroidism in the first and third trimesters with obstetric and perinatal outcomes: a prospective cohort study

BackgroundMild hypothyroidism, including subclinical hypothyroidism (SCH) and isolated maternal hypothyroxinemia (IMH), is fairly common in pregnant women, but its impact on pregnancy outcomes is less clear, especially mild hypothyroidism in late pregnancy. ObjectiveTo evaluate the impact of SCH and IMH in the first and third trimesters, respectively, on obstetric and perinatal outcomes. Study DesignThis large prospective study was conducted at the International Peace Maternity and Child Health Hospital (IPMCH) in Shanghai. 52,027 pregnant women who underwent the first-trimester antenatal screening at IPMCH were consecutively enrolled from January 2013 to December 2016. To evaluate the impact of maternal SCH and IMH in the first trimester on pregnancy outcomes, participants were divided into three groups according to thyroid function in the first trimester: first-trimester euthyroidism group (n= 33,130), first-trimester SCH group (n= 884), and first-trimester IMH group (n= 846). Then, to evaluate the impact of maternal SCH and IMH in the third trimester on pregnancy outcomes, the first-trimester euthyroidism group was subdivided into three groups according to thyroid function in the third trimester: third-trimester euthyroidism group (n= 30,776), third-trimester SCH group (n= 562), and third-trimester IMH group (n= 578). Obstetric and perinatal outcomes, including preterm birth (PTB), preeclampsia, gestational hypertension, gestational diabetes mellitus (GDM), large for gestational age (LGA), small for gestational age, macrosomia, cesarean section, and fetal demise were measured and compared between those in either SCH/IMH group and euthyroid group. Binary logistic regression was used to assess the association of SCH or IMH with these outcomes. Results34,860 pregnant women who had first (weeks 8–14) and third trimester (weeks 30–35) thyrotropin and free thyroxine concentrations available were included in the final analysis. Maternal SCH in the first trimester was linked to a lower risk of GDM (aOR 0.64, 95% CI 0.50–0.82) compared with the euthyroid group. However, third-trimester SCH is associated with heightened rates of PTB (aOR 1.56, 95%CI 1.10–2.20), preeclampsia (aOR 2.23, 95%CI 1.44–3.45), and fetal demise (aOR 7.00, 95%CI 2.07–23.66) compared with the euthyroid group. IMH in the first trimester increased risks of preeclampsia (aOR 2.14, 95% CI 1.53–3.02), GDM (aOR 1.45, 95%CI 1.21–1.73), LGA (aOR 1.64, 95%CI 1.41–1.91), macrosomia (aOR 1.85, 95%CI 1.49–2.31) and cesarean section (aOR 1.35, 95%CI 1.06–1.74), while IMH in the third trimester increased risks of preeclampsia (aOR 2.85, 95%CI 1.97–4.12), LGA (aOR 1.49, 95%CI 1.23–1.81) and macrosomia (aOR 1.60, 95%CI 1.20–2.13) compared with the euthyroid group. ConclusionThis study indicates that while first-trimester SCH did not elevate the risk for adverse pregnancy outcomes, third-trimester SCH was linked to several adverse pregnancy outcomes. IMH in the first and third trimesters was associated with adverse pregnancy outcomes, yet the impact varied by trimester. These results suggest the timing of mild hypothyroidism in pregnancy may be pivotal in determining its effects on adverse pregnancy outcomes and underscore the importance of trimester-specific evaluations of thyroid function.

Assessing the causal relationship between obesity and hypothyroidism using Mendelian randomization.

To explore the causal relationship between obesity and hypothyroidism and identify risk factors and the predictive value of subclinical hypothyroidism (SCH) in obese patients using Mendelian randomization, this study employed five Mendelian randomization methods (MR Egger, Weighted Median, Inverse Variance Weighted, Simple Mode, and Weighted Mode) to analyze clinical data from 308 obese patients at the People's Hospital of Xinjiang Uygur Autonomous Region, from January 2015 to June 2023. Patients were divided based on thyroid function tests into normal (n = 173) and SCH groups (n = 56). Comparative analyses, along with univariate and multivariate logistic regression, were conducted to identify risk factors for SCH in obese patients. A significant association between obesity and hypothyroidism was established, especially highlighted by the inverse variance weighted method. SCH patients showed higher ages, thyroid-stimulating hormone levels, and thyroid autoantibody positivity rates, with lower T4 and FT4 levels. Age, FT4, thyroid autoantibodies, TPO-Ab, and Tg-Ab were confirmed as risk factors. The predictive value of FT4 levels for SCH in obesity was significant, with an Area Under the Curve (AUC) of 0.632. The study supports a potential causal link between obesity and hypothyroidism, identifying specific risk factors for SCH in obese patients. FT4 level stands out as an independent predictive factor, suggesting its utility in early diagnosis and preventive strategies for SCH.

The role of non-invasive oscillometric method to detect aortic stiffness in patients with subclinical hypothyroidism

Introduction Subclinical hypothyroidism (SCH) is a biochemical condition that is diagnosed when peripheral free thyroid hormone levels are within normal reference laboratory range but serum thyroid-stimulating hormone (TSH) levels are mildly elevated. The aim of this study was to investigate the relationship between SCH and arterial stiffness using two different non-invasive methods, including echocardiography and oscillometric arteriography. Material and Methods The study included 33 newly diagnosed SCH patients and 34 age- and gender-matched healthy controls. Systolic and diastolic diameters and elastic parameters of the aorta were calculated by 2D Transthoracic echocardiography (TTE). Central blood pressure and aortic stiffness values of patient groups were measured noninvasively from the brachial artery using Mobil-O-Graph arteriography. Pulse wave velocity (PWV) and augmentation index (AIx) were used as arterial stiffness indicators. Results There was no significant difference between SCH and control groups with regard to age, gender, and body mass index (BMI). Aortic strain and aortic distensibility, were significantly lower in the SCH group than in the control group (p < 0.001). PWV and AIx which measured by Mobil-O-Graph arteriography were found to be significantly higher in the subclinical hypothyroid group compared to the control group (p < 0.05). Conclusion Aortic stiffness assessed by TTE and Mobil-O-Graph arteriography deteriorated in patients with SCH after excluding other cardiovascular risk factors. The assessment of aortic stiffness by the oscillometric method was easy and useful for widespread clinical use.

Correlation between Serum Ferritin and Thyroid Hormones Level in Children with Thalassemia

Background: Thalassemia is a group of hereditary blood disorder characterized by reduced or absent globin chain synthesis resulting in transfusion dependent anaemia and iron overload. Due to regular blood transfusion and inadequate chelation therapy patient develop multiorgan dysfunction. Objectives: To find any correlation between serum ferritin and thyroid hormones level in children with transfusion dependent thalassemia. Methods: This cross-sectional study was carried out in the department of Paediatrics and department of Medicine, Sylhet MAG Osmani Medical College Hospital between June, 2021 to May, 2022, on one hundred children with transfusion dependent thalassemia who were on more than 12 times blood transfusion but did not take any chelation therapy and whose serum ferritin level were &gt; 1000 ng/ml. Assessment of their thyroid hormones level and statistically its correlation with serum ferritin were done. Result: A total of 53 (53%) male and 47 (47%) female were included in this study. The mean age of the patients was 9.47 ±3.63 years. Mean serum ferritin was 1980±1126.19 ng/ml, mean serum TSH was 3.55±2.08 µIU/ml, mean serum free T4 was 1.10±0.18 ng/ml, mean serum free T3 was 3.64±0.37 pg/ml. Subclinical hypothyroidism and euthyroid were found in 20 patients (20%) and 80 patients (80%) respectively. No overt hypothyroidism or hyperthyroidism were found. Mean serum ferritin in subclinical hypothyroid and euthyroid were 2407±995.37 ng/ml and 1875.59±1131.18 ng/ml respectively which difference was statistically significant (P value &lt;0.05). Scattered diagram was done and it showed linear correlation between serum ferritin and serum TSH of subclinical hypothyroid group. No linear correlation was found between serum ferritin and F.T3 and F.T4 on scattered diagram. Positive (Pearson) correlation was found between serum ferritin and serum TSH of subclinical hypothyroid group and strong positive (Pearson) correlation (r=0.74, P=0.02) was found between them. Conclusion: This study showed that good percentages of children with transfusion dependent thalassemia are suffering from subclinical hypothyroidism. There is positive correlation between serum ferritin level and subclinical hypothyroidism.

The effect of subclinical hypothyroidism on hormonal and metabolic profiles and ovarian morphology in patients with polycystic ovary syndrome: a cross-sectional study

Objectives Polycystic ovary syndrome (PCOS) and subclinical hypothyroidism (SCH) are prevalent gynecological conditions. However, the interrelationship between the two remains elusive. This study aims to elucidate the association between these conditions and determine the potential impact of SCH on the physiological and metabolic characteristics of patients with PCOS. Methods This cross-sectional study enrolled 133 patients with PCOS from our Hospital. Participants were categorized into two groups: those with PCOS + SCH (n = 58) and those with PCOS (n = 75). Serum hormonal levels, metabolic markers, ovarian volume, and follicle count were compared between the groups. Results There was a significant difference in BMI between the two groups, with a higher prevalence of obesity in the PCOS + SCH group (p = .014). Compared to the PCOS group, patients with PCOS + SCH had significantly higher levels of TSH (p < .001), triglycerides (p = .025), and HOMA-IR (p < .001), while LH levels were significantly lower (p = .048). However, multivariate linear regression analysis revealed that TSH, triglycerides, LH, and HOMA-IR were not determinants for the occurrence of SCH in patients with PCOS. Additionally, there was a notable reduction in follicle count in the left ovary for the PCOS + SCH group compared to the PCOS group (p = .003), and the overall follicle diameter of the PCOS + SCH group was also smaller (p = .010). Conclusion SCH may exert effects on the physiological and metabolic profiles of patients with PCOS. Further investigation into the relationship between these disorders is warranted to delineate their clinical implications.

Evaluation of the Association between Insulin Resistance and Subclinical Hypothyroidism Using Triglyceride-Glucose Index: a Cross-Sectional Study.

Thyroid disorders and diabetes mellitus are often known to co-exist, implying an interrelationship between thyroid dysfunction and insulin resistance. Triglyceride-glucose (TyG) index is a relatively new surrogate marker of insulin resistance, which is cost-effective and easily calculated with routine lab tests. Data about association of subclinical hypothyroidism (SCH) and insulin resistance, especially with reference to TyG index, is lacking. To evaluate the association of SCH and insulin resistance using the TyG index by comparing its value in patients with SCH and age- and gender-matched euthyroid controls. Also, to determine if there is a correlation between TyG index values and thyroid profile parameters (TSH, FT3 and FT4) in both study groups. Thirty-five patients with SCH and an equal number of age- and gender-matched euthyroid controls were included in the present study. The TyG index was calculated for each group and compared. The correlation between TyG index and thyroid profile parameters (TSH, FT3 and FT4) was also assessed. The TSH values were significantly higher in the SCH group (6.6±1.7 µIU/mL) than the control one (2.5±1.2 µIU/mL; p<0.0001). There was no significant difference in FT3 in the SCH group (2.93±0.49 pg/ mL) and the control one (3.05±0.64 pg/mL; p=0.310). The level of FT4 was also not found to be significantly different in SCH subjects (1.23±0.44 ng/dL) and controls (1.4±0.42 ng/dL; p=0.077). The TyG index values were significantly higher in the SCH group (4.8±0.2) as compared to the control one (4.7±0.2; p = 0.015). The TyG index did not show any significant correlation with the thyroid parameters in any of the two groups. There is a positive association between SCH and insulin resistance in terms of TyG index. This index may thus be helpful in early screening and management of such patients for insulin resistance related conditions like diabetes mellitus, metabolic syndrome and cardiovascular disorders.

Insulin Resistance Among Children and Adolescents with Subclinical Hypothyroidism: A Case-Control Study

Background: Subclinical hypothyroidism (SCH) is marked by elevated thyroid-stimulating hormone (TSH) levels while maintaining normal thyroxine levels. Although the link between insulin resistance (IR) and overt hypothyroidism is well-established, less is known about this relationship in children and adolescents with SCH. Objectives: This study aimed to explore the association between insulin resistance and SCH in individuals aged 4 to 18 years. Methods: In this case-control study, 30 patients with SCH aged 4 - 18 from the Endocrinology Clinic at Imam Reza Hospital, Shiraz, Iran, were chosen as the case group through convenient sampling. Additionally, 30 healthy children and adolescents from the same clinic were randomly selected as controls. Exclusion criteria included positive Anti-TPO, goiter, previous thyroid disease, systemic diseases, chronic or acute diseases, diabetes, and a BMI ≥ 85%. Levels of TSH, insulin, fasting blood sugar (FBS), triglycerides, cholesterol, low-density lipoprotein, and high-density lipoprotein were compared between the groups. Data were analyzed using SPSS 25. Results: The study found that levels of FBS, insulin, and Homeostatic Model Assessment for IR (HOMA-IR) were significantly higher in the SCH group than in the control group. There was a significant correlation between TSH levels and both insulin levels and IR in the SCH group. Subclinical hypothyroidism was found to significantly increase the risk of developing IR among pediatric patients compared to healthy controls. Conclusions: Overall, our findings indicate a positive correlation between TSH levels and IR in children with SCH. Additionally, HOMA-IR levels were significantly higher with elevated TSH in the SCH group compared to healthy children. It is recommended that IR be evaluated and treated timely in SCH patients to prevent future complications.

Subclinical Hypothyroidism Predicted Adverse Cardiovascular Events in Patients with Ejection Fraction Preserved Heart Failure.

Subclinical hypothyroidism (SH) increases the risk of cardiovascular events, however the influence of SH on prognosis of ejection fraction preserved heart failure (HFpEF) is not fully understood. In this prospective observational study, patients with HFpEF were divided into euthyroidism group (n = 413) and SH group (n = 79). Patients were followed up for at least 30 months to examine the association between SH and cardiovascular events in patients with HFpEF. The primary end point was composite cardiovascular events (cardiovascular death and re-hospitalization). The patients underwent flow-mediated dilation (FMD) measurement by ultrasound in order to value endothelial function. The rate of composite cardiovascular events was higher in SH group than in euthyroidism group (54.49% and 26.36%, respectively; p < 0.001). The higher risk of cardiovascular events in SH group was primarily due to a higher risk of re-hospitalization compared to euthyroidism group (45.56% and 20.58%, respectively; p < 0.001). The rate of cardiovascular death was higher in SH group than in euthyroidism group (13.92% and 5.81%, respectively; p = 0.017). Cox proportional hazards regression showed that SH (hazard ratios [HR] 1.921, 95% confidence interval [CI] 1.139-3.240), level of TSH (HR 1.025, 95% CI 1.010-1.054), age (HR 1.017, 95% CI 1.002-1.034), LVEF (HR 0.975, 95% CI 0.953-0.996), atrial fibrillation (HR 1.581, 95% CI 1.083-2.307), eGFR (HR 0.987, 95% CI 0.978-0.997), and NYHA cardiac function (HR 2.342, 95% CI 1.649-3.326) were independent predictors of cardiovascular events in patients with HFpEF (all P < 0.05). Subclinical hypothyroidism was associated with increased cardiovascular events and death in patients with HFpEF.

Fetuin-A level in patients with untreated thyroid dysfunction

Fetuin-A, a plasma glycoprotein, has been demonstrated to play an essential role in the pathogene­sis of several metabolic disorders. This study aimed to estimate fetuin-A serum level in patients with newly diagnosed primary hyperthyroidism (PHT) and subclinical hypothyroidism (SCH) and to examine its correlation with thyroid hormones level, age and sex of patients. The study involved 90 patients with untreated thyroid dysfunction verified with thyroid function test (45 with PHT and 45 with SCH) and 90 control subjects. Triiodo­thyronin (T3), tetraiodothyronin (T4), and thyroid stimulating hormone (TSH) serum concentrations were measured with enzyme-linked fluorescent assay (ELFA), fetuin-A concentration was measured with enzyme-linked immunosorbent assay (ELISA). It was demonstrated that the level of fetuin-A was significantly higher in the PHT group as compared with the control group and showed a significant positive correlation with the T3 level. In the SCH group, the level of fetuin-A was significantly lower and showed a negative correlation with TSH level. Fetuin-A level rose with age in the PHT group and was unaffected by sex in all studied groups. The perfect AUC value obtained for fetuin-A in the comparison between PHT and SCH groups suggests its potential use as a reliable diagnostic marker to differentiate between these two thyroid conditions.

Structural and Functional Alterations of Hippocampal Subfields in Patients With Adult-Onset Primary Hypothyroidism.

Hypothyroidism is often associated with cognitive and emotional dysregulation; however, the underlying neuropathological mechanisms remain elusive. The study aimed to characterize abnormal alterations in hippocampal subfield volumes and functional connectivity (FC) in patients with subclinical hypothyroidism (SCH) and overt hypothyroidism (OH). This cross-sectional observational study comprised 47 and 40 patients with newly diagnosed adult-onset primary SCH and OH, respectively, and 53 well-matched healthy controls (HCs). The demographics, clinical variables, and neuropsychological scale scores were collected. Next, the hippocampal subfield volumes and seed-based FC were compared between the groups. Finally, correlation analyses were performed. SCH and OH exhibited significant alterations in cognitive and emotional scale scores. Specifically, the volumes of the right granule cell molecular layer of the dentate gyrus (GC-ML-DG) head, cornu ammonis (CA) 4, and CA3 head were reduced in the SCH and OH groups. Moreover, the volumes of the right molecular layer head, CA1 body, left GC-ML-DG head, and CA4 head were lower in SCH. In addition, the hippocampal subfield volumes decreased more significantly in SCH than OH. The seed-based FC decreased in SCH but increased in OH compared with HCs. Correlation analyses revealed thyroid hormone was negatively correlated with FC values in hypothyroidism. Patients with SCH and OH might be at risk of cognitive decline, anxiety, or depression, and exhibited alterations in volume and FC in specific hippocampal subfields. Furthermore, the reduction in volume was more pronounced in SCH. This study provides novel insights into the neuropathological mechanisms of brain impairment in hypothyroidism.

Assessment of Clinical and Biochemical Cardiac Risk Factors in Patients with Subclinical Hypothyroidism: A Cross-sectional Study

Introduction: Cardiovascular diseases (CVD) are among the leading causes of morbidity and mortality in the current era, and the focus is gradually shifting towards identifying the risk factors and pathways leading to CVD. While hypothyroidism has been extensively studied and linked to CVD risk, the association between subclinical hypothyroidism and CVD risk factors is not well established. Aim: To investigate the association between subclinical hypothyroidism and cardiac risk factors such as obesity indicators {Body Mass Index (BMI) and Waist-hip Ratio (WHR)}, blood pressure, and lipid parameters. Materials and Methods: This cross-sectional study was conducted at the Department of Medicine, ESI PGIMSR, Basaidarapur, New Delhi, India, from December 2020 to April 2022. The study included 200 patients, with 100 patients recruited in the subclinical hypothyroidism group (Thyroid Stimulating Hormone (TSH) &gt;4.8 μIU/mL with normal fT4) and 100 patients with euthyroid status (TSH 0.5-4.8 μIU/mL and normal fT4) included in the comparison group. Both groups were assessed for CVD risk factors including obesity indicators (BMI and WHR), blood pressure, and lipid parameters. The two groups were analysed for statistical significance using Student’s t-test. Results: Both groups had similar age distributions. However, there was a greater percentage of female patients in the subclinical hypothyroidism group (61%) compared to the euthyroid group (52%). As expected, TSH levels in the subclinical hypothyroidism group were significantly higher than in the euthyroid group. The subclinical hypothyroidism group recorded significantly higher mean values of BMI, Systolic Blood Pressure (SBP), Diastolic Blood Pressure (DBP), total cholesterol, and triglycerides, which were higher by 18%, 17%, 17%, 41%, and 16% compared to the euthyroid group, respectively. Other parameters like WHR and Low-Density Lipoprotein-Cholesterol (LDL-C) were found to be raised in subclinical hypothyroidism compared to the euthyroid group, while High-Density Lipoprotein-Cholesterol (HDL-C) levels were significantly lower by 16% in subclinical hypothyroidism. Conclusion: Subclinical hypothyroidism is significantly associated with cardiac risk factors like obesity indicators (BMI and WHR), blood pressure, and lipid parameters.

Use of transient elastography for hepatic steatosis and fibrosis evaluation in patients with subclinical hypothyroidism.

To evaluate the association between subclinical hypothyroidism and hepatic steatosis and fibrosis using the noninvasive diagnostic methods transient hepatic elastography (TE) and controlled attenuation parameter (CAP) in patients with subclinical hypothyroidism. This was a cross-sectional study including women with confirmed spontaneous subclinical hypothyroidism and an age- and body mass index (BMI)-matched control group without thyroid disease or circulating antithyroperoxidase (anti-TPO) antibodies. Exclusion criteria were age > 65 years, thyroid-stimulating hormone (TSH) > 10.0 mIUI/L, BMI ≥ 35 kg/m2, diabetes, or other chronic liver diseases. Liver stiffness was classified according to TE values (in kPa) and ranged from absence of fibrosis (F0) to advanced fibrosis (F3). Hepatic steatosis was classified according to CAP values (in dB/m) and ranged from low-grade (S1) to advanced (S3) steatosis. Of 68 women enrolled, 27 were included in the subclinical hypothyroidism group and 41 in the control group. Advanced steatosis (S3) was more frequent in the subclinical hypothyroidism group (25.9% versus 7.3%, respectively, p = 0.034). Circulating anti-TPO was an independent factor associated with advanced steatosis (odds ratio 9.5, 95% confidence interval 1.3-68.3). In multiple linear regression analysis, TE values (which evaluated fibrosis) correlated negatively with free thyroxine levels. The results of this study strengthen the hypothesis that hepatic steatosis is associated with autoimmune (positive anti-TPO) subclinical hypothyroidism, independently from BMI. However, subclinical hypothyroidism alone does not appear to be associated with a significantly increased risk of hepatic fibrosis.

Atherogenic Indices as Early Predictors of Cardiovascular Diseases among Patients with Subclinical and Overt Hypothyroidism in a Tertiary Care Hospital, Karnataka: A Cross-sectional Study

Introduction: Hypothyroidism is a common health issue that decreases the functional ability of life. It is strongly associated with altered levels of serum lipids, leading to an increased risk of Cardiovascular Disease (CVD). Lipid profile and Atherogenic Indices (AIs) can serve as better markers for evaluating CVD risk. Aim: The aim of this cross-sectional study is to evaluate the role of dyslipidaemia and AIs as predictors of CVD risk among patients with Subclinical Hypothyroidism (SCH) and Overt Hypothyroidism (OH) compared to euthyroid controls. Materials and Methods: The present cross-sectional study was conducted at the Clinical Biochemistry Section of Mandya Institute of Medical Sciences in Mandya, Karnataka, India from August to September 2019. A total of 150 subjects aged between 25-60 years were enrolled. Fasting lipid profile and Thyroid Function Test (TFT) were analysed. Based on TFT results, subjects were categorised into SCH, OH, and euthyroid groups. Data on anthropometry {(height, weight, Body Mass Index (BMI), and Blood Pressure (BP)}, lipid profile, Atherogenic Index of Plasma (AIP), Castelli Risk Index-I (CRI-I), CRI-II, and Atherogenic Coefficient (AC) were collected. Statistical analysis was performed using Pearson’s correlation and Receiver Operating Characteristic (ROC) curve analysis. Results: Out of the 150 subjects, 104 (69.3%) were females and 46 (30.7%) were males, with a mean age of 41.08±11.24 years. Both the SCH and OH groups showed statistically significant dyslipidaemic changes and elevated AIs compared to euthyroid controls. Among OH patients, there was a statistically significant positive correlation between TSH and Total Cholesterol (TC) (r=0.463), Low-Density Lipoprotein cholesterol (LDL-c) (r=0.448), CRI-I (r=0.414), CRI-II (r=0.412), and AC (r=0.411). Conversely, there was a statistically significant negative correlation between fT3 and TC (r=-0.393), LDL-c (r=-0.363), CRI-I (r=-0.300), CRI-II (r=-0.301), and AC (r=-0.298). Among the AIs, AIP showed the maximum Area Under the Curve (AUC) in both the SCH (0.707) and OH (0.747) groups. Conclusion: AIs aid in the better assessment of dyslipidaemia and CVD risk compared to lipid profile alone in hypothyroid subjects. Incorporating AIs enables early prediction of high-risk individuals for CVD risk.

Gender-specific Association between Thyroid Stimulating Hormone and Haematological Indices in Hypothyroid Patients: A Cross-sectional Study

Introduction: Hypothyroidism has long been known to cause metabolic deceleration, including its effects on haematopoietic tissue, leading to anaemia. Anaemia and hypothyroidism can co-exist and present challenges for each other, resulting in a decline in quality of life. Aim: To address the gender-specific association of Thyroid Stimulating Hormone (TSH) with various haematological indices among a cohort of hypothyroid patients. Materials and Methods: A cross-sectional observational study was conducted at a tertiary care teaching hospital in Hyderabad, Telangana, India, from October 2022 to February 2023, after obtaining ethical clearance from the institutional ethics committee. A total of 347 newly diagnosed, biochemically proven hypothyroid patients attending the hospital were included in the study. The patients were divided into subclinical and overt hypothyroid groups based on their TSH values and thyroxine levels. All patients underwent blood tests for a complete blood count, including all haematological indices such as erythrocyte count, Haemoglobin (Hb), Packed Cell Volume (PCV), Mean Corpuscular Volume (MCV), Mean Corpuscular Haemoglobin (MCH), Mean Corpuscular Haemoglobin Concentration (MCHC), and Red cell Distribution Width (RDW). Gender-based stratification of the study population was performed. Data were analysed using the Student’s unpaired t-test, Chi-square test, and univariate linear regression with Statistical Package for the Social Sciences (SPSS) version 22.0. Results: The study highlighted a high prevalence of anaemia among overt hypothyroid patients 88 (54%) compared to subclinical hypothyroid patients 63 (34.24%). Moreover, the prevalence of anaemia was higher in females than in males. The most common type of anaemia encountered was microcytic anaemia, followed by normocytic anaemia. Linear regression analysis yielded a positive correlation between TSH and all haematological parameters, including RDW. This correlation was especially significant among females. Conclusion: TSH affected all the haematological parameters, including RDW, and the association was stronger in females as compared to males in both subclinical and overt hypothyroidism.

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.

Correlation of subclinical hypothyroidism with sarcopenia and its components in the Chinese older adults.

To identify the correlation of thyroid function and subclinical hypothyroidism (SCH) with sarcopenia and its components in the older Chinese adults. Older adults were recruited and divided into SCH group and non-SCH group. Free triiodothyronine (FT3), free thyroxine (FT4) and thyroid-stimulating hormone (TSH) were measured by electrochemiluminescence. Appendicular skeletal muscle mass (ASM) was measured, and skeletal muscle index (SMI) was further calculated. Grip strength was measured. Physical performance was graded by the Short Physical Performance Battery (SPPB) scores of the gait speed test, chair stand test and balance test. Of the 240 older adults included, 48 (20.00%) presented with SCH. The prevalence of sarcopenia in SCH group was higher than that in non-SCH group (33.33% v.s. 18.75%). Grip strength was significantly lower in patients with SCH than those without sarcopenia. In terms of physical performance, 6-meter gait speed and SPPB score were lower in subjects with SCH than those without SCH, while 5 sit-to-stand movements was longer score in subjects with SCH than those without SCH. SCH was significantly correlated with sarcopenia, while FT3, FT4, and TSH levels were not. SCH was significantly correlated with low muscle strength and low muscle mass, but not with low physical performance. FT3 level was positively correlated with grip strength and SMI. TSH level was negatively correlated with grip strength, 6-meter gait speed, and SPPB score, but positively correlated with the time of 5 sit-to-stand movements. SCH is a risk factor for sarcopenia in the older adults and correlated with low muscle strength and low muscle mass, but not with low physical performance. FT3, FT4 and TSH levels are associated with sarcopenia components, but not with sarcopenia.