Thyroid dysfunction among patients assessed by thyroid function tests at a tertiary care hospital: a retrospective study.

Introduction: previous studies in African populations have not extensively described the spectrum of thyroid dysfunction using the profile of thyroid hormones. Although iodine deficiency is a common thyroid disorder in Africa, it does not represent the entire spectrum of thyroid dysfunction seen in patients. This retrospective study aimed to describe the spectrum of thyroid dysfunction among patients seen at the Korle-Bu Teaching Hospital (KBTH), a tertiary care hospital in Accra, Ghana. Methods: a retrospective analysis of medical records of all consultations on thyroid disorders seen at the Internal Medicine Department of KBTH between January 2019 and December 2021 was conducted. Information on patient demographics, and thyroid hormone profiles (triiodothyronine - FT3, thyroxine - FT4, and thyroid stimulating hormone - TSH) were extracted and subjected to descriptive statistics. The thyroid hormone profiles of the subjects were analyzed and classified into thyroid dysfunction categories using guidelines from the American Thyroid Association (ATA). Results: out of the 215 patients with thyroid disorders enrolled, 85.1% (n=183) were females and 14.9% (n=32), were males. The mean age of patients was 45±14 years, with most of the patients within the age range of 31-50 years (49.3%; n=106). The most reported thyroid function dysfunction was primary hyperthyroidism (57.7%), followed by primary hypothyroidism (22.3%), subclinical hyperthyroidism (9.3%), euthyroid sick syndrome (6.5%), and subclinical hypothyroidism (4.6%) respectively. Conclusion: primary hyperthyroidism was the most commonly diagnosed thyroid dysfunction. Hyperthyroidism has been associated with cardiac morbidity and mortality. Timely interventions are required to reduce the morbidity risks and burden associated with the hyperthyroid state.

Hypothyroidism.

Hypothyroidism, the deficiency of thyroid hormone, is a common condition worldwide. It affects almost all body systems and has a wide variety of clinical presentations from being asymptomatic to, in rare cases, life threatening. The classic symptoms of hypothyroidism include fatigue, lethargy, weight gain, and cold intolerance; however, these symptoms are non-specific and the diagnosis is typically made on biochemical grounds through serum thyroid function tests. The most common cause of hypothyroidism is chronic autoimmune thyroiditis (Hashimoto's thyroiditis), although other causes, including drugs (such as amiodarone, lithium, and immune checkpoint inhibitors), radioactive-iodine treatment, and thyroid surgery, are frequent. Historically, severe iodine deficiency was the most common cause. Reference ranges for thyroid function tests are based on fixed percentiles of the population distribution, but there is increasing awareness of the need for more individualised reference intervals based on key factors such as age, sex, and special circumstances such as pregnancy. Levothyroxine monotherapy is the standard treatment for hypothyroidism; it is safe and inexpensive, restores thyroid function tests to within the reference range, and improves symptoms in the majority of patients. However, 10% of patients have persistent symptoms of ill health despite normalisation of thyroid function tests biochemically and a substantial proportion of patients on levothyroxine have thyroid-stimulating hormone concentrations outside the reference range. Ongoing symptoms despite levothyroxine treatment has led to some patients using liothyronine or desiccated thyroid extract. Taken together, these factors have led to intense debate around the treatment thresholds and treatment strategies for hypothyroidism. In this Seminar, we review the epidemiology, genetic determinants, causes, and presentation of hypothyroidism; highlight key considerations and controversies in its diagnosis and management; and provide future directions for research.

Association between systemic lupus erythematosus and autoimmune thyroid dysfunction in pediatric population: a single center experience.

BACKGROUND: Systemic Lupus Erythematosus (SLE) patients are more likely than the general population to suffer from thyroid illness. The major goal was to assess the thyroid dysfunctions due to immunological factors in Egyptian SLE children and how they are related to the course and severity of the illness. METHODS: Fifty children and adolescents with SLE are included in this cross-sectional observational study. Every patient underwent a thorough physical examination and a comprehensive history taking. An enzyme-linked immunosorbent assay (ELISA) approach was used to evaluate the thyroid profile, anti-thyroglobulin (Anti-TG), and anti-thyroid peroxidase (anti-TPO) antibodies. RESULTS: Of the 50 patients, the female: male ratio (F: M = 7:1) was 44 females and 6 males (12%). They were between the ages of 5 and 17. Out of the patients, thirty-two (64%) had thyroid dysfunctions, 19 (38%) had euthyroid sick syndrome, ten (20%) had overt hypothyroidism, three (6%) had subclinical hypothyroidism, and none had hyperthyroidism. Of the 50 patients, one (2%) had increased anti-TPO, whereas all other patients had normal anti-TG levels. A statistically significant negative correlation (p-value 0.007) was seen between the disease duration and free thyroxine (FT4). Furthermore, a significant negative correlation (p-values 0.015 and 0.028) was found when comparing the disease duration with thyroid antibodies (anti-TG and anti-TPO). CONCLUSION: In Juvenile Systemic Lupus Erythematosus (JSLE), thyroid dysfunctions can be identified. The disease duration but not its activity was significantly correlated with thyroid antibodies. For children with JSLE, thyroid function testing should be done on a regular basis. It is preferable to carry out additional thyroid antibody tests when necessary.

The correlation between the thyroid function and urinary iodine/creatinine ratio of pregnant women attending a tertiary hospital in Beijing, China, during different trimesters.

OBJECTIVE: This study investigated the correlation between thyroid function and urinary iodine/creatinine ratio (UI/Cr) in pregnant women during different trimesters and explored potential influencing factors. METHODS: In this cross-sectional study, serum levels of thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), and UI/Cr were measured in 450 pregnant women. Correlations were analyzed using Pearson's correlation coefficient and multiple linear regression. Subgroup analyses were performed based on age, body mass index (BMI), parity, gestational age, education, occupation, and family history of thyroid disorders. RESULTS: UI/Cr was positively correlated with FT4 levels in the first and second trimesters, particularly in women with older age, higher BMI, multiparity, higher education, and employment. No significant correlations were found between UI/Cr and TSH or FT3 levels. CONCLUSION: UI/Cr is positively correlated with FT4 levels in early pregnancy, especially in women with certain risk factors. Regular monitoring of iodine status and thyroid function is recommended for pregnant women to ensure optimal maternal and fetal health.

The association between depression and thyroid function.

Background: Emerging evidence indicated that depression is currently one of the most burdensome diseases worldwide, and it can lead to a variety of functional physical impairments. However, the studies estimated the association between depression and thyroid function remain sparse. We aimed to investigate the association between depression and thyroid function in the American population. Methods: A cross-sectional analysis was performed using the data from the National Health and Nutrition Examination Survey conducted from 2007 to 2012. In the 12,502 adults aged 20-80 years, weighted linear regression models and multiple logistic regression models were applied to evaluate the association between depression and thyroid function indicators. The thyroid indicators investigated were mainly free thyroxine (FT4), total T4 (TT4), free triiodothyronine (FT3), total T3 (TT3), thyroid-stimulating hormone (TSH), and antithyroperoxidase antibody (TPOAb), thyroglobulin (Tg) and antithyroglobulin antibody (TgAb). Results: The final results were reached after adjusting for various confounding factors. In the stratification analysis of subgroups divided by age, depression was significantly negatively correlated with FT4, FT3, and TT3 in both younger adults (p = 0.00122, p < 0.00001, and p = 0.00003) and older adults (p = 0.00001, p = 0.00004, and p < 0.00001). In contrast, depression was significantly negatively correlated with TT4 and Tg in older adults (p = 0.00054, p = 0.00695) and positively correlated in younger adults (p = 0.01352, p < 0.00001). The subgroup analysis by gender revealed that depression was significantly negatively correlated with FT4, FT3, and TT3 in both adult males (p = 0.0164, p = 0.0204, and p = 0.0050) and adult females (p ≤ 0.0001, p < 0.0001, and p < 0.0001), which was more prominent in females. The positive correlation between depression symptoms and TPOAb was only found in adult females (p = 0.0282) and younger adults (p = 0.00488). Conclusion: This study confirmed a significant correlation between depressive and thyroid function and it varied among different genders or age. In the future, more prospective studies are needed to reveal these findings and confirm a causal relationship between them.

Time-restricted eating with or without a low-carbohydrate diet improved myocardial status and thyroid function in individuals with metabolic syndrome: secondary analysis of a randomized clinical trial.

BACKGROUND: Obesity and metabolic syndrome (MetS) have become urgent worldwide health problems, predisposing patients to unfavorable myocardial status and thyroid dysfunction. Low-carbohydrate diet (LCD) and time-restricted eating (TRE) have been confirmed to be effective methods for weight management and improving MetS, but their effects on the myocardium and thyroid are unclear. METHODS: We conducted a secondary analysis in a randomized clinical diet-induced weight-loss trial. Participants (N = 169) diagnosed with MetS were randomized to the LCD group, the 8 h TRE group, or the combination of the LCD and TRE group for 3 months. Myocardial enzymes and thyroid function were tested before and after the intervention. Pearson's or Spearman's correlation was assessed between functions of the myocardium and thyroid and cardiometabolic parameters at baseline. RESULTS: A total of 162 participants who began the trial were included in the intention-to-treat (ITT) analysis, and 57 participants who adhered to their assigned protocol were involved in the per-protocol (PP) analysis. Relative to baseline, lactate dehydrogenase, creatine kinase MB, hydroxybutyrate dehydrogenase, and free triiodothyronine (FT3) declined, and free thyroxine (FT4) increased after all 3 interventions (both analyses). Creatine kinase (CK) decreased only in the TRE (- 18 [44] U/L, P < 0.001) and combination (- 22 [64] U/L, P = 0.003) groups (PP analysis). Thyrotropin (- 0.24 [0.83] µIU/mL, P = 0.011) and T3 (- 0.10 ± 0.04 ng/mL, P = 0.011) decreased in the combination group (ITT analysis). T4 (0.82 ± 0.39 µg/dL, P = 0.046), thyroglobulin antibodies (TgAb, 2 [1] %, P = 0.021), and thyroid microsomal antibodies (TMAb, 2 [2] %, P < 0.001) increased, while the T3/T4 ratio (- 0.01 ± 0.01, P = 0.020) decreased only in the TRE group (PP analysis). However, no significant difference between groups was observed in either analysis. At baseline, CK was positively correlated with the visceral fat area. FT3 was positively associated with triglycerides and total cholesterol. FT4 was negatively related to insulin and C-peptide levels. TgAb and TMAb were negatively correlated with the waist-to-hip ratio. CONCLUSIONS: TRE with or without LCD confers remarkable metabolic benefits on myocardial status and thyroid function in subjects with MetS. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04475822.

Analysis of risk factors for papillary thyroid carcinoma and the association with thyroid function indicators.

Objective: This study aims to analyze the relationship between papillary thyroid carcinoma (PTC) and various factors. Methods: The study involved two groups-PTC patients and non-PTC controls. We utilized binary logistic regression and Least Absolute Shrinkage and Selection Operator (Lasso) regression for variable selection and risk factor analysis. Correlation analysis was performed using Spearman's rank correlation. The diagnostic value of thyroid stimulating hormone (TSH) levels for PTC was assessed using Receiver Operating Characteristic (ROC) curves. Results: PTC patients exhibited higher body mass index (BMI) (23.71 vs. 22.66, p<0.05) and TSH levels (3.38 vs. 1.59, p<0.05). Urinary iodine concentration (UIC) was an independent predictor of PTC (OR=1.005, p<0.05). The optimal TSH threshold for PTC diagnosis was 2.4 mIU/L [The Area Under the Curve (AUC)=67.3%, specificity=71.4%, sensitivity=70.1%]. TSH levels positively correlated with BMI (r=0.593, p<0.05) and UIC (r=0.737, p<0.05). Conclusions: UIC may be an independent predictor of PTC, and TSH levels have some diagnostic value for identifying PTC.

Causal relationship between thyroid function and multiple sclerosis: A bidirectional Mendelian randomization study.

An association between thyroid function and multiple sclerosis (MS) has been reported in several observational studies, but the causal relationship between them is still unclear. Thus, this study used a bidirectional Mendelian randomization (MR) to investigate the associations between thyroid function and MS. Bidirectional MR was used to explore the causal relationship between thyroid function (thyroid-stimulating hormone [TSH], free thyroxine [FT4], hyperthyroidism, and hypothyroidism) and MS. Genome-wide association study (GWAS) data of thyroid function and MS were obtained from the ThyroidOmics Consortium and the FinnGen Consortium, respectively. Inverse-variance weighted method (IVW) was the primary analysis method to assess causality with Weighted median, MR-Egger regression, weighted mode, and simple mode as auxiliary methods. Sensitivity analyses were performed using heterogeneity tests, horizontal pleiotropy tests and leave-one-out method. There was a positive causal relationship between TSH and MS (IVW: OR = 1.202, 95% CI: 1.040-1.389, P = .013), and no strong evidence was found for an effect of FT4 (IVW: OR = 1.286, 95% CI: 0.990-1.671, P = .059), hypothyroidism (IVW: OR = 1.247, 95% CI: 0.961-1.617, P = .096), and hyperthyroidism (IVW: OR = 0.966, 95% CI: 0.907-1.030, P = .291) on the risk of MS. In the reverse MR results, there was no causal relationship between MS and TSH (IVW: ß = -0.009, P = .184), FT4 (IVW: ß = -0.011, P = .286), hypothyroidism (IVW: OR = 0.992, 95% CI: 0.944-1.042, P = .745), and hyperthyroidism (IVW: OR = 1.026, 95% CI: 0.943-1.117, P = .549). Cochran's Q test, MR-Egger intercept test, MR-PRESSO global test, and Leave-one-out did not observe horizontal pleiotropy and heterogeneity. In conclusion, MR analysis supported a positive causal relationship between TSH and MS.

Fetal sexual dimorphism of maternal thyroid function parameters during pregnancy, a single center retrospective real-world study.

Introduction: Thyroid function during pregnancy fluctuates with gestational weeks, seasons and other factors. However, it is currently unknown whether there is a fetal sex-specific thyroid function in pregnant women. The purpose of this study was to investigate the fetal sex differences of maternal thyroid-stimulating hormone (TSH) and free thyroxine (FT4) in pregnant women. Methods: This single-center retrospective real-world study was performed by reviewing the medical records of pregnant women who received regular antenatal health care and delivered liveborn infants in Shanghai First Maternity and Infant Hospital (Pudong branch), from Aug. 18, 2013 to Jul. 18, 2020. Quantile regression was used to evaluate the relationship between various variables and TSH and FT4 concentrations. The quantile regression also evaluated the sex impact of different gestational weeks on the median of TSH and FT4. Results: A total of 69,243 pregnant women with a mean age of 30.36 years were included. 36197 (52.28%) deliveries were boys. In the three different trimesters, the median levels (interquartile range) of TSH were 1.18 (0.66, 1.82) mIU/L and 1.39 (0.85, 2.05) mIU/L, 1.70 (1.19, 2.40) mIU/L; and the median levels (interquartile range) of FT4 were 16.63 (15.16, 18.31) pmol/L, 14.09 (12.30, 16.20) pmol/L and 13.40 (11.52, 14.71) pmol/L, respectively. The maternal TSH upper limit of reference ranges was decreased more in mothers with female fetuses during gestational weeks 7 to 12, while their FT4 upper limit of the reference ranges was increased more than those with male fetuses. After model adjustment, the median TSH level was 0.11 mIU/L lower (P <0.001), and FT4 level was 0.14 pmol/L higher (P <0.001) for mothers with female fetuses than those with male fetuses during gestational weeks 9 to 12. Discussion: We identified sexual dimorphism in maternal thyroid function parameters, especially during 9-12 weeks of pregnancy. Based on previous research, we speculated that it may be related to the higher HCG levels of mothers who were pregnant with girls during this period. However, longitudinal studies are needed to determine if fetal sex differences impact the maternal thyroid function across pregnancy.

Thyroid Profile in Liver Cirrhosis Patients-Correlation with Disease Severity and Recommendations for Clinical Practice: A Cross-sectional Observational Study.

INTRODUCTION: Liver diseases are increasingly recognized as significant public health concerns in India, prompting investigations into novel approaches for assessing disease severity and prognosis. Recognizing the potential utility of thyroid hormone levels in these assessments, we conducted an observational cross-sectional study at our tertiary care hospital. Our study included 89 patients aged 12 years and above, admitted to medicine wards with ultrasound-diagnosed liver cirrhosis, excluding pregnant women and those on thyroid-altering medications. OBSERVATIONS: Our findings revealed a male-to-female ratio of 4.23:1, with the majority of patients falling within the 40-60 age-group, averaging 46.93 years. Notably, 87.6% of patients exhibited thyroid abnormalities, primarily low free T3 (FT3) syndrome and subclinical hypothyroidism. Classifying patients according to Child-Pugh (CP) score, 2.2% were CP class A, 22.5% were CP class B, and the remaining 75.3% were CP class C. Across all CP classes, low FT3 syndrome was prevalent, particularly in CP class C. Correlations between thyroid hormone levels and liver disease severity, assessed via CP and model for end-stage liver disease (MELD) scoring systems, were observed. Specifically, FT3 levels demonstrated a negative correlation with liver disease severity (p = 0.001), while no significant correlations were found for free T4 (FT4) and thyroid-stimulating hormone (TSH) levels. Based on our findings, we recommend routine thyroid function testing for all liver cirrhosis patients, irrespective of disease severity, to facilitate early detection and intervention. However, our study had limitations, including a small sample size and a precision error of 10% due to resource constraints for thyroid function testing. Moreover, reliance solely on ultrasound for liver cirrhosis diagnosis may lead to missed diagnoses, highlighting the need for complementary noninvasive tests such as FibroScan and aspartate aminotransferase to platelet ratio index (APRI) scores. CONCLUSION: Our study underscores the importance of considering thyroid function in the management of liver cirrhosis patients and provides valuable insights for enhancing clinical practice in this context.

Establishment of reference intervals of thyroid-related hormones for adults with normal liver function in Zhejiang Province by indirect method.

Objective: Thyroid disorders are prevalently diagnosed yet face significant challenges in their accurate identification in China. Predominantly, the reference intervals (RIs) currently in use across Chinese medical facilities derive from company-provided data, lacking stringent scientific validation. This practice underscores the urgent necessity for establishing tailored RIs for thyroid-related hormones, specifically tailored to the coastal area populations. Such refined RIs are imperative for empowering clinicians with the precise tools needed for the accurate diagnosis of both overt and subclinical thyroid conditions. Methods: This investigation analyzed the medical histories of 6021 euthyroid individuals mainly from East coastal area of China between June 2019 and December 2020. The cohort comprised residents of coastal areas, focusing on extracting insights into the regional specificity of thyroid hormone levels. A thorough examination protocol was implemented, encompassing inquiries into thyroid health history, ultrasound screenings, palpations during thyroid surgery, detections of thyroid antibodies, and reviews of medication histories. Adherence to the CLSI C28-A3 guidelines facilitated the derivation of RIs for thyroid-related hormones, subsequently juxtaposed against those provided by commercial entities. Results: The study delineated the following gender- and age-specific RIs for Thyroid-Stimulating Hormone (TSH): for males under 50 years, 0.57-3.37; males over 50 years, 0.51-4.03; females under 50 years, 0.53-3.91; and females over 50 years, 0.63-4.31. Further analysis revealed the RIs for Free Thyroxine (FT4), Free Triiodothyronine (FT3), Total Thyroxine (TT4), and Total Triiodothyronine (TT3) amongst males and females, with notable distinctions observed between the two genders and across age brackets. These findings are in stark contrast to the standardized intervals provided by manufacturers, particularly highlighting differences in TT3 and FT3 levels between genders and a tendency for TSH levels to increase with age. Conclusion: This research successfully establishes refined RIs for thyroid-related hormones within the Chinese coastal area populations, taking into account critical demographic factors such as gender and age. These tailored RIs are anticipated to significantly enhance the diagnostic accuracy for thyroid diseases, addressing the previously noted discrepancies with manufacturer-provided data and underscoring the importance of regionally and demographically adjusted reference intervals in clinical practice.

Relationship of Thyroid Volume and Function with Ankle-Brachial Index, Toe-Brachial Index, and Toe Pressure in Euthyroid People Aged 18-65.

Background and Objectives: The interrelationship between thyroid function and the state of the cardiovascular system has been investigated both in preclinical and human studies. However, it remains unclear whether there is any association between thyroid hormones and features of subclinical cardiovascular dysfunction in euthyroid patients. Material and Methods: This study involved 45 people (females: 57.8%) with no thyroid disease who, during planned hospitalization, underwent thyroid ultrasound, determination of biochemical parameters of thyroid function, and measurement of ankle-brachial index (ABI) and toe-brachial index (TBI). People with signs of acute illness or a deterioration of their health were excluded. Results: Significant correlations were found between free triiodothyronine (FT3) and several parameters of both ABI (R = 0.347; p = 0.019 for the mean ABI taken from right side and left side values) and TBI (R = 0.396; p = 0.007 for the mean TBI taken from right side and left side values), as well as the maximal toe pressure (TP) taken from right side and left side values (R = 0.304; p = 0.045). Thyrotropin (TSH) was shown to be significantly correlated only with the maximal TBI value (taken from right side and left side values) (R = 0.318; p = 0.033), whereas free thyroxin (FT4) was shown to be significantly correlated only with the minimal TBI value (taken from right side and left side values) (R = 0.381; p = 0.01). Thyroid volume (TV) was shown to be correlated with TP (R = 0.4; p = 0.008 for the mean TP taken from right side and left side values) and some parameters of TBI value (R = 0.332; p = 0.028 for the mean TBI taken from right side and left side values), but no significant correlations were found between TVand ABI parameters. Patients with a mean ABI value ≤ 1.0 or a mean TBI value ≤ 0.75 have lower TSH, FT3, FT4, and TV than the rest of the study population, but the difference was statistically significant only for FT3. Conclusions: Even in a population of euthyroid patients with no diagnosed thyroid disease, there are some significant correlations between the volume and function of the thyroid gland and the selected features of subclinical cardiovascular dysfunction such as ABI and TBI.

Association of Dietary Inflammatory Index and Thyroid Function in Patients with Hashimoto's Thyroiditis: An Observational Cross-Sectional Multicenter Study.

Background and Objectives: The available research suggests that dietary patterns with high inflammatory potential, as indicated by a high DII score, may exacerbate inflammation and potentially influence thyroid function. Therefore, the aim of this study was to investigate the associations between the inflammatory potential of a diet and thyroid function in adults with Hashimoto's thyroiditis (HT). Materials and Methods: A total of 149 adults diagnosed with Hashimoto's thyroiditis were enrolled in this observational, cross-sectional, multicenter study. The Dietary Inflammatory Index (DII®) was calculated using a 141-item food frequency questionnaire (FFQ). The serum levels of the thyroid-stimulating hormone (TSH), free thyroxine (fT4), thyroid peroxidase antibodies (TPO-Ab), and high-sensitivity C-reactive protein (hsCRP) were determined. Results: The DII® scores ranged from -3.49 (most anti-inflammatory) to +4.68 (most pro-inflammatory), whereas three DII® tertile ranges were defined as <-1.4, -1.39 to +1.20, and >+1.21, respectively. Participants in tertile 1 (more anti-inflammatory diet) had significantly higher levels of fT4 than those adhering to a more pro-inflammatory diet (p = 0.007). The levels of hsCRP and TSH appeared to increase with increasing the DII® score, but without statistical significance. A significant association was found between the DII® and TSH (ß = 0.42, p < 0.001) and between DII® and free thyroxine (ß = 0.19, p < 0.001). After adjustment for age, gender, energy intake, and physical activity, a significant positive correlation remained between the DII® and TSH (ß = 0.33, p = 0.002) and between the DII® and body mass index (BMI) (ß = 0.14, p = 0.04). Conclusions: Adherence to an anti-inflammatory diet appears to be beneficial in patients with Hashimoto's thyroiditis, suggesting that dietary modification aimed at lowering DII® levels may be a valuable strategy to improve clinical outcomes in these patients.

Thyroid function, physical activity and sedentary behaviour: A bidirectional two-sample Mendelian randomisation study.

Background: The interinfluence of thyroid function and daily physical activity (PA) remains unclear. We examined the causal relationship between genetically proxied thyroid-related traits; hypothyroidism, hyperthyroidism, thyroid stimulating hormone (TSH) and free thyroxine (FT4), and daily PA measures; leisure screen time (LST) and moderate-to-vigorous physical activity (MVPA), using Mendelian randomisation (MR) analysis. Methods: We used genome-wide association study (GWAS) data from the ThyroidOmics Consortium and the most comprehensive meta-analysis on PA, comprising data on hypothyroidism (n = 53 423), hyperthyroidism (n = 51 823), TSH within the reference range (n = 54 288), fT4 within the reference range (n = 49 269), LST (n = 526 725), and MVPA (n = 608 595) to conduct a bidirectional two-sample MR analysis. The inverse variance weighted (IVW) method was employed as the primary result. Sensitivity analyses included MR-Egger, weighted median, and MR pleiotropy residual sum and outlier (MR-PRESSO) regression. Similar investigations were conducted in the reverse direction. Finally, we analysed a multivariable MR using body mass index (BMI)-related traits GWAS data. Results: In the primary IVW analysis, an increase in genetically proxied TSH levels significantly increased LST (correlation coefficient (ß) = 0.040; 95% confidence interval (CI) = 0.020-0.061, P = 9.776 × 10-5). The multivariable MR analysis indicated that the positive causal effect still existed when considering the influence of BMI (MVMR-IVW: ß = 0.042; 95% CI = 0.011-0.073, P = 0.007). Conversely, there was no evidence to suggest that PA impacts thyroid function. Conclusions: The results of this MR analysis suggest that thyroid function influences daily PA. The positive association between TSH and LST is not confounded or mediated by BMI.

Thyroid functions and insulin resistance in pregnant Sudanese women.

BACKGROUND: The thyroid function test (free triiodothyronine [FT3], free thyroxine [FT4], and thyroid-stimulating hormone [TSH]) is one of the key determinant of glucose homeostasis by regulating the balance of insulin. Thyroid dysfunction alters glucose metabolism, leading to insulin resistance (IR). This study aimed to assess the association between thyroid function and IR in pregnant Sudanese women. METHOD: A cross-sectional study was conducted in Saad Abuelela Hospital, Khartoum-Sudan, from January to April 2021. Obstetric/sociodemographic characteristics were gathered through questionnaires. Serum TSH, FT3, FT4, fasting plasma glucose (FPG), and fasting insulin levels were measured and evaluated, and IR was estimated using the homeostatic model assessment for insulin resistance (HOMA-IR) equation. RESULTS: In total, the study included 127 pregnant women with a median age of 27.0 years (interquartile range [IQR] 23.0‒31.2) and a median gestational (IQR) age of 25.0 (IQR 25.0‒27.0) weeks. The medians (IQRs) of the TSH, FT3, and FT4 were 1.600 (1.162‒2.092) IU/ml, 2.020(1.772‒2.240) nmol/l, and 10.70 (9.60‒11.90) pmol/l, respectively. The median (IQR) of the FPG and fasting blood insulin level was [69.0 (62.00‒78.00) mg/dl] and [5.68(2.99‒11.66) IU/ml], respectively. The median (IQR) of the HOMA-IR level was 0.9407 (0.4356‒2.1410). There was a positive correlation between HOMA -IR and FT3 levels (r = 0.375; P < 0.001) and a negative correlation with FT4 levels (r= -0.312; P < 0.001). Also, a significant positive correlation was found between fasting insulin levels and FT3 levels (r = 0.438; P < 0.001) and a negative correlation with FT4 levels (r= -0.305; P < 0.001). CONCLUSIONS: This study indicated that FT3 has positive correlation with HOMA-IR, while FT4 has negative correlation among healthy pregnant women without a history of thyroid dysfunction. This may indicate screening of euthyroid pregnant women for thyroid dysfunction and IR. Further studies are needed.

Mendelian randomization analysis reveals no causal relationship between thyroid function and sarcopenia-related traits.

Background: Recent research has indicated a potential association between thyroid function and sarcopenia, but the specific mechanisms and a definitive causal relationship have yet to be established. Therefore, the objective of this study is to examine the potential causal connection between thyroid function and sarcopenia-related traits, including hand-grip strength, appendicular lean mass (ALM), and walking pace. Methods: The study used a bi-directional two-sample MR design, with thyroid function examined as the exposure and sarcopenia-related traits as the outcome in the first stage, and then reversed in the second stage. The genetic instruments for thyroid function were obtained from a comprehensive meta-analysis involving 271,040 participants. Data on sarcopenia-related traits based on GWASs were collected from the UK Biobank, which includes up to 461,026 European participants. The estimates for MR were calculated using the inverse-variance weighted (IVW) method, and several sensitivity analyses were performed. Results: After applying the Bonferroni correction for multiple testing, our MR analyses revealed no significant impact of thyroid function liability on sarcopenia-related traits. Similarly, our reverse MR analysis did not provide evidence supporting the influence of liability to sarcopenia-related traits on thyroid function. The results of the primary IVW MR analyses were largely in line with those obtained from our sensitivity MR analyses. Conclusion: Our research findings do not suggest a link between thyroid function and sarcopenia-related traits. The associations identified in epidemiological studies may be influenced, at least in part, by shared biological mechanisms or environmental confounders.

Effects of thyroid hormones modify the association between pre-pregnancy obesity and GDM: evidence from a mediation analysis.

Objective: Conflicting associations have been noted between thyroid function and gestational diabetes mellitus (GDM), with indications that pre-pregnancy BMI might influence these relationships. This study aims to examine the effect of thyroid hormone indices and their mediation role on the risk of GDM. Methods: Pregnant women in our study were recruited from the Zhoushan Pregnant Women Cohort, Zhejiang Province, China. Participants who had their first prenatal follow-up and measured thyroid biomarkers in the first trimester, and oral glucose tolerance test (OGTT) records in the second trimester were eligible for inclusion in this study. The data were extracted from the Electronic Medical Record System database, at Zhoushan Maternal and Child Care Hospital. Maternal information about sociodemographic and health-related characteristics was extracted from the dataset. A unique personal identification number was provided to link both datasets. Multivariate logistic regression models were applied to investigate the correlations between thyroid hormone indices with GDM. The interaction effects of first-trimester thyroid hormone indices with pre-pregnancy BMI on GDM risk using a generalized linear regression model. Furthermore, the mediation analysis was used to explore the potential mediating effects of thyroid hormone indices on the relationship between pre-pregnancy BMI and GDM. Results: Overall, 5895 pregnant women were included in this study. The first-trimester FT4, thyroid feedback quantile-based index (TFQI), thyrotropin index (TSHI) and thyrotroph thyroxine resistance index (TT4RI) levels were negatively associated with fasting blood glucose (FBG) and postprandial blood glucose (PBG2H) in the second trimester (all P<0.05); FT3 and the FT3-to-FT4 ratio levels were positively associated with PBG1H and PBG2H in the second trimester (all P<0.05). Moreover, there were significant correlations between the highest quartile FT4, FT3, FT3-to-FT4 ratio, TSHI, and TFQI with GDM (all P < 0.05). The mediating effect of thyroid hormone parameters was 24.9% on the association between pre-pregnancy BMI and GDM. Conclusions: In conclusion, the low FT4, high FT3-to-FT4 ratio, and low TFQI in the first trimester significantly increase the risk of GDM and should be given more attention. Furthermore, increased pre-pregnancy BMI might partially increase the risk of GDM by influencing the body's thyroid function.

Preoperative Thyroid-Stimulating Hormone Levels and Three-Year Mortality in Elderly Hip Fracture Patients: Insights from a Prospective Cohort Study.

BACKGROUND It is unclear whether preoperative thyroid-stimulating hormone (TSH) level is correlated with long-term mortality in the elderly after hip fracture surgery. We aimed to assess the association between TSH levels and 3-year mortality in these patients. MATERIAL AND METHODS We enrolled patients aged 65 and above who had hip fracture surgery and thyroid function tests upon admission from 2018 to 2019. Patients were categorized based on TSH median value, quartiles, or thyroid function status. The median follow-up time was 3.1 years. Cox proportional hazards models were used to examine the correlation between TSH levels and mortality, adjusting for covariates. RESULTS Out of 799 eligible patients, 92.7% (741/799) completed the follow-up, with 20.6% (153/741) of those having died by the end of the follow-up. No statistically significant differences in mortality risks were found when stratified by TSH median value (HR 0.88, 95% CI 0.64-1.22, P=0.448) or quartiles (HR ranging from 0.90 to 1.13, P>0.05). Similarly, when categorized based on admission thyroid function status, patients who presented with hypothyroidism, subclinical hypothyroidism, hyperthyroidism, and subclinical hyperthyroidism upon admission did not demonstrate a statistically significant difference in mortality risk compared to those who were considered euthyroid (HR 1.34, 95% CI 0.72-2.49, P=0.359; HR 0.77, 95% CI 0.38-1.60, P=0.489; HR 1.15, 95% CI 0.16-8.30, P=0.890; HR 1.07, 95% CI 0.34-3.38, P=0.913, respectively). CONCLUSIONS Admission TSH is not significantly associated with 3-year mortality in geriatric patients after hip fracture surgery.

Chemotherapy for post-menopausal women with early breast cancer seems not to result in clinically significant changes in thyroid function.

OBJECTIVE: Adjuvant chemotherapy is often indicated in patients diagnosed with early breast cancer (EBC). Among others, weight gain is one of the observed side effects of both chemotherapy and other cancer treatments; however, the mechanism is not well-described. In this study, we aimed to assess thyroid function before and shortly after the course of chemotherapy for EBC. METHODS: This is a prospective cohort study of women diagnosed with EBC. The main outcome was the thyroid function and body weight before and after completing chemotherapy. Secondary outcomes were the presence of thyroid autoantibodies and treatment radiation dosage. We included 72 patients treated with adjuvant chemotherapy, whereas 59 patients also received supraclavicular locoregional radiotherapy. Triple-negative breast cancer (BC) patients receiving chemoimmunotherapy were excluded. RESULTS: After the chemotherapy, we observed an increase in thyroid-stimulating hormone (p = 0.03) and a decrease in free-thyroxine (p = 0.0006), with no significant weight change. The prevalence of autoimmune thyroiditis was low. On average 3 months post-chemo, we found no statistically significant difference in the thyroid function of women treated versus not treated with supraclavicular locoregional radiotherapy. CONCLUSIONS: Although statistically significant changes in thyroid hormones were observed, this study suggests no obvious clinically significant changes in thyroid function in women with early BC after the course of chemotherapy. The decrease in thyroid function was not related to autoimmunity, non-thyroidal illness, radiotherapy, or high-dose corticosteroids. Further studies with a longer follow-up of thyroid function after adjuvant chemotherapy and supraclavicular locoregional radiotherapy are needed.

Clinical features and Surgical Outcomes of Thyroid Goitre Presenting to Ear, Nose and Throat Department of Queen Elizabeth Central Hospital, Blantyre, Malawi.

Introduction: In Malawi there is a perception that goitre is common and causes significant public health and economic burdens. The purpose of this study was to assess the demographic distribution, clinical presentation, investigations, management, outcomes and complications of goitre seen at Queen Elizabeth Central Hospital (QECH), Blantyre, Malawi. Method: A single hospital-based descriptive retrospective study from January 2017 to December 2018 for all patients presenting with goitre. Results: Out of 9073 patients who presented to ENT department, 105 patients presented with goitre representing 1% of all patients seen during the study period. The Male: Female ratio was 1:25. The mean symptom duration with goitre was 4 years (SD +/- 6.4). Thyroid function test results were available in 54 patients and out of these, 53(98%) patients were euthyroid. Ultrasound scan (USS) reports were available in 44 patients, of these 32(73%) were multinodular goitres. In 70 cases, pathology results were available and showed that 20% were thyroid cancers and that papillary thyroid carcinoma was the commonest cancer (64%). Two recurrent laryngeal nerve injuries were recorded in 79 surgical procedures representing 2.5% of patients (6.3% overall complication rate). Inpatient stay ranged from 2 days to 49 days (median 3 days). Conclusion: Goitre at our centre is more common in women than in men. One in five patients in this cohort had thyroid cancers. This prevalence is higher than other areas in the world highlighting the need for cytology services on every patient before surgery and histology services after surgery. Recurrent laryngeal nerve injury and other complications were infrequent demonstrating local high safety of thyroid surgery, despite late presentation to the ENT department.