Low thyroxine serves as an upstream regulator of ecophysiological adaptations in Ansell's mole-rats.

Introduction: About 10% of all rodent species have evolved a subterranean way of life, although life in subterranean burrows is associated with harsh environmental conditions that would be lethal to most animals living above ground. Two key adaptations for survival in subterranean habitats are low resting metabolic rate (RMR) and core body temperature (Tb). However, the upstream regulation of these traits was unknown thus far. Previously, we have reported exceptionally low concentrations of the thyroid hormone (TH) thyroxine (T4), and peculiarities in TH regulating mechanisms in two African mole-rat species, the naked mole-rat and the Ansell's mole-rat. Methods: In the present study, we treated Ansell's mole-rats with T4 for four weeks and analyzed treatment effects on the tissue and whole organism level with focus on metabolism and thermoregulation. Results: We found RMR to be upregulated by T4 treatment but not to the extent that was expected based on serum T4 concentrations. Our data point towards an extraordinary capability of Ansell's mole-rats to effectively downregulate TH signaling at tissue level despite very high serum TH concentrations, which most likely explains the observed effects on RMR. On the other hand, body weight was decreased in T4-treated animals and Tb was upregulated by T4 treatment. Moreover, we found indications of the hypothalamus-pituitary-adrenal axis potentially influencing the treatment effects. Conclusion: Taken together, we provide the first experimental evidence that the low serum T4 concentrations of Ansell's mole-rats serve as an upstream regulator of low RMR and Tb. Thus, our study contributes to a better understanding of the ecophysiological evolution of the subterranean lifestyle in African mole-rats.

Higher serum free thyroxine levels are associated with increased risk of hip fractures in older men.

Overt and subclinical hyperthyroidism are associated with an increased fracture risk, but whether thyroid hormones are associated with fracture risk in individuals with normal thyroid-stimulating hormone (TSH) has mostly been investigated in women. Therefore, we investigated if serum levels of free thyroxine (FT4) or TSH are associated with fracture risk in Swedish men. We followed (median 12.2 yr) elderly men (n = 1825; mean age 75, range 69-81 yr) participating in the Gothenburg and Malmö subcohorts of the prospective, population-based MrOS-Sweden study. The statistical analyses included Cox proportional hazards regression. Men receiving levothyroxine treatment were excluded. In our total cohort, serum FT4 (per SD increase) was associated with increased risk of major osteoporotic fractures (MOFs; n = 479; fully adjusted hazard ratio [HR] 1.14, 95% CI, 1.05-1.24) and hip fractures (n = 207; HR 1.18, 95% CI, 1.04-1.33). Also, in men with normal TSH (n = 1658), FT4 (per SD increase) was significantly associated with increased risk of MOF and hip fractures. Furthermore, men in the highest FT4 quartile had a 1.5-fold increase in hip fracture risk compared with men in the three lower FT4 quartiles, both in the total population and in men with normal TSH (fully adjusted: HR 1.45, 95% CI, 1.04-2.02 and HR 1.51, 95% CI, 1.07-2.12, respectively). In contrast, the risk of MOF was not statistically different in the highest FT4 quartile compared with the three lower FT4 quartiles. Finally, serum TSH was not associated with fracture risk after full adjustment for covariates. In conclusion, serum FT4, but not serum TSH, is a predictor of hip fracture risk in elderly Swedish men. Additionally, there was an association between FT4 (per SD increase) and the risk of MOF.

Spring and fall blood concentrations of adrenocorticotropic hormone, insulin, and thyroxine in healthy horses in Saskatchewan.

Objective: To characterize concentrations of adrenocorticotropic hormone (ACTH), insulin, and thyroxine (T4) at 2 times of the year in healthy horses in Saskatchewan. Animals and procedure: A prospective, observational study was carried out in 52 healthy, client-owned horses. Inclusion criteria were no recent travel outside of Saskatchewan, normal physical examination findings, and no history or evidence of ongoing illness. Blood concentrations of ACTH, insulin and T4 were determined by chemiluminescence. Samples were collected in spring and fall and compared using the paired Student's t-test or Wilcoxon signed-rank test. Generalized estimating equations were used to assess the associations between ACTH, T4, and insulin concentrations and gender, age, season, body condition score, glucose concentration, and breed. Results: There were increases in both ACTH and insulin concentrations in the fall compared to spring (P < 0.001 and P = 0.001, respectively). Other than season, insulin concentration was associated with breed, whereas ACTH concentration was associated with age. Finally, T4 concentration was associated with breed and glucose concentration, but not with season. Conclusion and clinical relevance: These results highlighted the differences between spring and fall concentrations of both ACTH and insulin in healthy horses residing in the Canadian prairie provinces, which are known for extreme differences in summer and winter temperatures as well as day length. Geographically adjusted reference values are necessary to account for these variations, to improve diagnostic accuracy. This is the first published Canadian study evaluating these factors and their associations with hormone concentrations in clinically healthy animals.

Concentrations sanguines printanières et automnales d'hormone adrénocorticotrope, d'insuline et de thyroxine chez des chevaux en bonne santé en Saskatchewan. Objectif: Caractériser les concentrations d'hormone adrénocorticotrope (ACTH), d'insuline et de thyroxine (T4) à 2 moments de l'année chez des chevaux en bonne santé en Saskatchewan. Animaux et procédure: Une étude observationnelle prospective a été réalisée auprès de 52 chevaux en bonne santé appartenant à des clients. Les critères d'inclusion étaient l'absence de voyage récent à l'extérieur de la Saskatchewan, les résultats normaux de l'examen physique et l'absence d'antécédents ou de signes de maladie persistante. Les concentrations sanguines d'ACTH, d'insuline et de T4 ont été déterminées par chimiluminescence. Des échantillons ont été collectés au printemps et à l'automne et comparés à l'aide du test de Student apparié ou du test du rang de signe de Wilcoxon. Des équations d'estimation généralisées ont été utilisées pour évaluer les associations entre les concentrations d'ACTH, de T4 et d'insuline et le sexe, l'âge, la saison, l'état corporel, la concentration de glucose et la race. Résultats: Il y avait une augmentation des concentrations d'ACTH et d'insuline à l'automne par rapport au printemps (P < 0,001 et P = 0,001, respectivement). Hormis la saison, la concentration d'insuline était associée à la race, alors que la concentration d'ACTH était associée à l'âge. Enfin, la concentration de T4 était associée à la race et à la concentration en glucose, mais pas à la saison. Conclusion et pertinence clinique: Ces résultats ont mis en évidence les différences entre les concentrations printanières et automnales d'ACTH et d'insuline chez les chevaux en bonne santé résidant dans les provinces des Prairies canadiennes, reconnues pour leurs différences extrêmes de températures estivales et hivernales ainsi que de durée du jour. Des valeurs de référence géographiquement ajustées sont nécessaires pour tenir compte de ces variations et améliorer la précision du diagnostic. Il s'agit de la première étude canadienne publiée évaluant ces facteurs et leurs associations avec les concentrations d'hormones chez des animaux cliniquement sains.(Traduit par Dr Serge Messier).

Evaluation of the therapeutic efficacy of different doses of LT4 in pregnant women with high-normal TSH levels and TPOAb positivity in the first half of pregnancy.

BACKGROUND: The objective was to investigate the efficacy of different doses of levothyroxine therapy among pregnant women exhibiting high-normal thyroid stimulating hormone levels and positive thyroid peroxidase antibodies throughout the first half of pregnancy. METHODS: Pregnant women exhibiting high-normal thyroid stimulating hormone levels and thyroid peroxidase antibodies positivity throughout the initial half of pregnancy were selected from January 2021 to September 2023. Based on the different doses of levothyroxine, the pregnant women were categorized into the nonintervention group (G0, 122 women), 25 µg levothyroxine intervention group (G25, 69 women), and 50 µg levothyroxine intervention group (G50, 58 women). Serum parameters, gastrointestinal symptoms, small intestinal bacterial overgrowth (SIBO), maternal and neonatal outcomes were compared after the intervention among the three groups. RESULTS: After the intervention, in the G25 and G50 groups, the thyroid stimulating hormone, triglyceride and low-density lipoprotein levels were notably less in contrast to those in the G0 group (P < 0.05). The rates of abdominal distension and SIBO in the G25 and G50 groups were notably lower in contrast to the G0 group (P = 0.043 and 0.040, respectively). The G50 group had a lower rate of spontaneous abortion and premature membrane rupture than the G0 group (P = 0.01 and 0.015, respectively). Before 11+ 2 weeks of gestation and at thyroid peroxidase antibodies levels ≥ 117 IU/mL, in contrast to the G0 group, the G50 group experienced a decreased rate of spontaneous abortion (P = 0.008). The G50 group had significantly higher newborn weight than the G0 group (P = 0.014), as well as a notably longer newborn length than the G0 and G25 groups (P = 0.005). CONCLUSIONS: For pregnant women with high-normal thyroid stimulating hormone levels and thyroid peroxidase antibodies positive during the first half of pregnancy, supplementation with 50 µg levothyroxine was more effective in improving their blood lipid status and gastrointestinal symptoms, reducing the incidence of SIBO and premature rupture of membranes, and before 11+2 weeks, TPOAb ≥ 117 IU/mL proved more beneficial in mitigating the risk of spontaneous abortion.

Serum FT3/FT4, but not TSH is associated with handgrip strength in euthyroid U.S. population: evidence from NHANES.

Objective: Although several studies have examined the relationship between thyroid function and muscle strength, their population primarily derived from Asian areas, and their results were controversial. Thus, this study aimed to explore the association between thyroid function and handgrip strength (HGS) in the U.S. population. Methods: A total of 1,067 participants from NHANES were categorized into three different age groups including young (<45 years), middle (45~64 years), and old (≥65 years) age groups. Thyroid function was measured by the competitive binding immune-enzymatic assays, while HGS was examined by a trained evaluator using a dynamometer. The weighted multiple linear regression models were used to examine the association between thyroid function and handgrip strength. The restricted cubic splines were employed to explore the non-linear relationship between these two variables. All statistical analyses were performed using the SPSS version 20.0 and R software. Results: After adjustment for potential covariates, FT3/FT4, but not TSH was positively associated with HGS in middle age group (ß=0.091, t=2.428, P=0.016). The subgroup analysis by sex revealed that the positive association between FT3/FT4 and HGS was observed in the middle age group for both male and female participants (ß=0.163, t=2.121, P=0.035; ß=0.157, t=2.180, P=0.031). The RCS analysis showed a statistically significant non-linear association between FT3/FT4 and HGS in overall population (P for non-linear=0.026). After adjustment for covariates, men with low HGS had a significant lower FT3/FT4 than those without low HGS in old age group (P=0.013). There was a significant increase in TSH level for female participants with low HGS in old age group compared to those with normal HGS (P=0.048). Conclusions: This study demonstrated FT3/FT4, but not TSH, was positively associated with HGS in middle age group, and the different association was observed in men in middle age group when participants were stratified by sex. Future longitudinal cohort study should be conducted to reveal the causal relationship between thyroid function and muscle strength.

THE RELATION OF THYROID DISTURBANCE AND ISCHEMIC HEART DISEASE IN IRAQI PATIENTS.

This study conducted in Baghdad focused on patients with coronary heart disease admitted to three hospitals. The study included 60 Iraqi patients with coronary heart disease and a control group of 30 healthy individuals. Blood samples were collected from both groups after fasting. The study analyzed the demographic characteristics of the patients and control group, including age groups, sex distribution, and BMI. The majority of patients had hypertension, while 58.33% had diabetes. The study found that IHD patients had significantly higher T3 and T4 levels compared to the control group. However, there was no significant difference in TSH levels. The study also examined thyroid function parameters among different age groups and found no significant differences in individuals with hypothyroidism. The highest prevalence of hyperthyroidism was among individuals with hypertension, while the highest spread of hypothyroidism was among individuals with diabetes. The study observed significant differences in mean HbA1c levels among the three groups, with the highest levels in patients with hypothyroidism. In conclusion, this study suggests potential alterations in thyroid function associated with ischemic heart disease and emphasizes the need for further research on the clinical implications and underlying mechanisms involved.

The crosstalk between benign thyroid disease and breast cancer: A single center study.

This study aims to investigate the relationship between benign thyroid disease and breast cancer. The clinical study includes a total of 600 participants, divided into 2 groups: the control group (N = 300), which consists of individuals from the checkup population during the same periods, and the experimental group (N = 300), which consists of patients with breast cancer. General data of the participants, including age, tumor diameter, tumor staging, pathological classification, lymph node metastasis, and classification of benign thyroid disease, were collected and analyzed. The levels of TT3, TT4, FT3, FT4, TSH, TPOAb, and TgAb in blood samples from the experimental and control groups were determined using a radioimmune method. The levels of TPOAb, TgAb, and TSH in the experimental group were significantly higher than those in the control group, while the levels of TT3, TT4, FT3, and FT4 in the experimental group were significantly lower. The general data of the participants contributed to the appropriate sample size and allocation. Furthermore, benign thyroid disease contributes to the development of breast cancer by regulating the levels of TT3, TT4, FT3, FT4, TSH, TPOAb, and TgAb.

Associations among thyroid hormone levels and mean corpuscular volume in adults in the US: A cross-sectional examination of the NHANES 2007-2012 dataset.

Mean corpuscular volume (MCV) is an important indicator used to determine the etiology of anemia and is associated with a variety of diseases. However, the link between thyroid function and MCV has yet to be clarified. This study was thus developed to assess relationships between thyroid function and MCV in a population of adults in the US. Results from the National Health and Nutrition Examination Survey study performed from 2007 to 2012 were used to conduct a cross-sectional analysis. Key thyroid-related variables included in this analysis were thyroid-stimulating hormone, total thyroxine (TT4), free triiodothyronine (FT3), total triiodothyronine (TT3), free thyroxine (FT4), antithyroglobulin, thyroglobulin, and antithyroid peroxidase levels. Generalized linear regression models were employed when estimating associations between MCV quartiles and thyroid parameters in 8104 adults 18 + years of age. In these participants, the weighted mean (SD) MCV was 89.36 (0.16) fL, with thyroid-stimulating hormone levels of 1.86 (0.03) mIU/mL, FT3 levels of 3.20 (0.01) pg/mL, FT4 levels of 0.80 (0.01) ng/dL, TT3 levels of 115.09 (0.64) ng/dL, and TT4 levels of 7.81 (0.04) µg/dL. When analyses were not adjusted, higher MCV values were related to reduced serum levels of FT3, TT3, or TT4. Following adjustment for possible confounding variables, this significant negative correlation between MCV and levels of FT3, TT3, and TT4 remained, and subgroup analysis revealed that this negative correlation was present in the male group and in the age group >50 years, but not in the female group and in the age group less than or equal to 50 years. These results suggest a significant negative correlation between MCV and FT3, TT3, and TT4, and this negative correlation originated more from the male population and those older than 50 years of age. The underlying mechanisms warrant additional investigation.

[Relationship between thyroid function changes with work-/night-shifts and history of thyroid pathology among health personnel].

BACKGROUND: The study aim was to analyze the relationship between functional thyroid pathology and the exposure to work shifts / night shifts, and describe the most prevalent thyroid disorders based on the type of shift. METHODOLOGY: Cross-sectional study performed in the emergency department of a hospital in Almeria (Spain). Relationships between thyroxine and thyrotropin levels (TSH) and work shifts, professional category and history of thyroid pathology were analyzed. RESULTS: The study included 133 workers; 80.5% female, average age was 46.11 years (38 - 65), and 52% were part of the nursing staff; thyroid disorders were more frequent in female participants. Most participants (81.2%) had rotating shifts schedules and 11.3% night shifts (12.1% female and 7.7% male). Thyroid alterations were found in 27% of the participants (usually elevated TSH levels and normal thyroxine levels), particularly in those doing night shifts (61.1%). TSH alterations were more frequent in individuals doing night shifts than in rotating shifts (53.3 vs 13.0%; p<0.001). Individuals working night shifts had mean TSH values in the normal range, although significantly higher than the individuals in the rest of the shifts; thyroxine levels were found to be similar. No thyroid disorders were found in day shift participants. Night shift and a history of thyroid pathology were independent predictors of thyroid disorders. CONCLUSIONS: Night shift schedules and history of thyroid disorders are more frequent in female, both related to the presence of thyroid disorders, indicating the need to include the evaluation of these disorders in health surveillance programs and analyze gender differences.

Exploring oral drug delivery: In vitro release and mathematical modeling of hydrophobic drug (Na-L-thyroxine) and its cyclodextrin inclusion complex in chitosan microparticles.

Na-l-Thyroxine (Na-l-Thy) is a frequently prescribed synthetic hormone for hypothyroidism treatment. Despite its efficacy, its hydrophobic nature poses a challenge for achieving optimal bioavailability. To address this, researchers explored various delivery methods, including micro-formulations and nano-formulations, for precise and prolonged release of hydrophobic and hydrophilic drugs. In this study, we developed micro-formulations with cyclodextrin and chitosan. Docking studies identified γ-cyclodextrin as the preferred option for forming a stable complex with Na-l-Thyroxine compared to α, and ß-cyclodextrins. Two micro-formulations were prepared compared: Na-l-Thyroxine loaded on chitosan (CS + Na-l-Thy) and Na-l-Thyroxine and γ-cyclodextrin inclusion complex (IC) loaded on chitosan (CS + IC). CS + IC exhibited superior encapsulation efficiency (91.25 %) and loading capacity (18.62 %) compared to CS + Na-l-Thy (encapsulation efficiency: 70.24 %, loading capacity: 21.18 %). Characterization using FTIR, SEM, and TGA validated successful encapsulation of Na-l-Thy in spherical microparticles with high thermal stability. In-vitro release studies at pH 1.2 and 7.4 showed that the CS + IC microparticles displayed gradual, consistent drug release compared to CS + Na-l-Thy -Thy. Both formulations showed faster release at pH 1.2 than at pH 7.4. Reaction kinetics analysis of release studies of CS + Na-l-Thy and CS + IC were best described by Higuchi kinetic model and Korsemeyer-Peppas kinetic model respectively. This study suggests that the CS + IC microparticles are an effective and stable delivery system for sustained release of hydrophobic Na-l-Thy.

Association of pharmacogenomic, clinical and behavioural factors with oral levothyroxine (LT-4) dose of hypothyroid patients in Sri Lanka: a matched case control study.

BACKGROUND: Hypothyroidism is a common endocrine disorder that exerts a substantial influence on people all over the world. Levothyroxine (LT-4) is the drug of choice for the treatment of hypothyroidism and the starting oral dose is typically ranging from 1.5 to 1.7 µg/kg/day. The target is to achieve an optimum serum TSH level of 0.4-4.0 mIU/L; hence, the dose is titrated accordingly. Once the LT-4 dose is adjusted to obtain the target TSH level, it usually remains stable for a long period of time in most cases. However, some of the patients require frequent dose adjustments and some of them require unusually high doses. Therefore, the aim of this study is to determine the association of pharmacogenomic, clinical and behavioural factors with the oral levothyroxine (LT-4) dose requirement of hypothyroid patients in Sri Lanka. METHOD: This study will be conducted as a matched case-control study and will involve primary hypothyroid patients who visit the diabetes and endocrinology clinic at the National Hospital, Kandy, Sri Lanka. We will recruit a total of 292 cases and select 292 controls from the clinic who are matched in terms of age, sex and Body Mass Index (BMI). An interviewer-administered questionnaire will be used to collect data from the participants (n = 584). Of the 584 patients, blood samples will be collected from a sub-sample (n = 150) for DNA extraction. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) will be performed for single nucleotide polymorphisms (SNP) analysis. DISCUSSION: Frequent dose adjustments of levothyroxine cause a serious economic burden to the healthcare system. By identifying the root causes of the variations in LT-4 dosage, a more comprehensive comprehension of hypothyroidism and its management can be attained in Sri Lanka. Furthermore, upon identification of a positive association/correlation between genetic polymorphisms and the LT-4 dose, SNP profiles can be used as a possible genetic marker for dose adjustment determination in future patients.

Investigating the connection among thyroid function, sensitivity to thyroid hormones, and metabolic syndrome in euthyroid children and adolescents affected by type 1 diabetes.

OBJECTIVES: A connection between thyroid hormones (THs) and diverse metabolic pathways has been reported. We evaluated thyroid function and tissue sensitivity to THs in children and adolescents with T1D in comparison to euthyroid controls. Additionally, we investigate whether a relationship exists between sensitivity indices and metabolic parameters. METHODS: A retrospective analysis was conducted on 80 pediatric patients diagnosed with T1D. Clinical parameters, TSH, FT3, FT4, and the presence of MS were documented. Additionally, indices of peripheral sensitivity (FT3/FT4 ratio) and central sensitivity (TSH index, TSHI; TSH T4 resistance index, TT4RI; TSH T3 resistance index, TT3RI) were assessed. Thirty healthy subjects were considered as controls. RESULTS: The overall prevalence of MS was 7.27 %, with MS identified in 8 out of 80 (10 %) T1D subjects; none of the controls manifested MS (p<0.01). No significant differences were observed in indexes of tissue sensitivity to THs between subjects with or without MS (all p>0.05). Correlations between THs and indexes of THs tissue sensitivity and metabolic parameters in controls and T1D patients were noted. CONCLUSIONS: This study affirms a heightened prevalence of MS in children with T1D compared to controls and underscores the potential role of THs in maintaining metabolic equilibrium.

Takotsubo syndrome outcomes predicted by thyroid hormone signature: insights from cluster analysis of a multicentre registry.

BACKGROUND: Recently, abnormal thyroid function was shown to be common in patients with Takotsubo syndrome (TTS), being classified into "endocrine-type" and "stress-type" responses. The aim of this study was to investigate the association between thyroid homeostasis and TTS in a larger international registry. METHODS: In total 288 patients with TTS were enrolled through the GEIST multicentre registry from Germany, Italy and Spain. Thyrotropin (TSH), free T4 (FT4) and free T3 (FT3) concentrations were analysed at admission. Data were collected both retrospectively and prospectively from 2017 onwards. Primary endpoints included in-hospital and all-cause fatality, determined by cluster analysis using an unsupervised machine learning algorithm (k-medoids). FINDINGS: Three clusters were identified, classifying TTS with low (TSLT), high (TSHT) and normal (TSNT) thyroid output, based on TSH and FT4 levels in relation to the median thyroid's secretory capacity (SPINA-GT). Although TSH and FT4 concentrations were similar among survivors and non-survivors, these clusters were significantly associated with patient outcomes. In the longitudinal Kaplan-Meier analysis including in- and out-of-hospital survival, the prognosis related to concentrations of TSH, FT4, and FT3 as well as SPINA-GT, deiodinase activity (SPINA-GD) and clusters. Patients in the TSHT cluster and with cardiogenic shock had a lower initial left ventricular ejection fraction (LVEF). INTERPRETATION: This study suggests that thyroid hormones may impact the evolution and prognosis of TTS. The findings indicate that thyroid-derived biomarkers may help identify high-risk patients and pave the way for novel personalized and preventive therapeutic options. FUNDING: This research was not funded by any public, commercial, or not-for-profit agencies.

Radiofrequency ablation for papillary thyroid microcarcinoma close to the thyroid capsule versus far from the thyroid capsule: a retrospective study.

INTRODUCTION: The aim of this study was to evaluate the safety and efficacy of ultrasound-guided radiofrequency ablation (RFA) for the management of papillary thyroid microcarcinoma (PTMC) close to the thyroid capsule. MATERIAL AND METHODS: This was a retrospective study of 202 patients with PTMC who underwent RFA close to the thyroid capsule and 80 patients with PTMC who underwent RFA far from the thyroid capsule between June 2015 and December 2022. The follow-up time after RFA, change in size of tumour, location, thyroid function, the rates of PTMC disappearance, and complications were evaluated. RESULTS: A total of 202 patients with PTMC close to the thyroid capsule and 80 patients with PTMC far from the thyroid capsule successfully treated with RFA were studied. The thyroid function including free triiodothyronine (fT3), free thyroxine (fT4), triiodothyronine (T3), thyroxine (T4), and thyroid-stimulating hormone (TSH) showed no changes after RFA for one months in both groups. The tumour size was increased at 1, 3, and 6 months after RFA compared with pre-operative RFA in both groups. The tumour size was decreased at 12 and 24 months after RFA compared with pre-operative RFA both in both group. Seventy-nine PTMC close to the thyroid capsule and 30 PTMC far from the thyroid capsule completely disappeared as assessed by ultrasound examination. Eighty-four PTMC patients close to the thyroid capsule and 34 PTMC patients far from the thyroid capsule had minor complications after RFA treatment. The complication rates between the 2 groups were similar. CONCLUSION: Ultrasound-guided RFA seems to be an effective and safe method for patients with PTMC close to the thyroid capsule.

Aversion of surgical exploration in patients with complex ovarian cysts secondary to overt hypothyroidism: A series of three cases.

Long-standing, overt hypothyroidism-induced bilateral multiloculated ovarian cysts represent an infrequent occurrence. Our first case, presented with bilateral complex ovarian masses, exhibited overt hypothyroidism symptoms, including lethargy, weight gain and subfertility, prompting consideration for surgical intervention. Similarly, in the second case, a girl aged 11 years with stunting, delayed bone age and academic challenges was referred for surgical exploration due to bilateral complex ovarian masses. Both cases revealed elevated thyroid-stimulating hormone levels during preoperative workup. Commencing levothyroxine replacement therapy resulted in complete regression of ovarian cysts and substantial symptom improvement within an 8-week timeframe. The third case, a previously diagnosed patient with Hashimoto's thyroiditis, benefited from the lessons gleaned in managing the initial cases, responding well to levothyroxine therapy, thereby averting the necessity for surgery in all three instances. These cases underscore the significance of considering thyroid function in the evaluation of ovarian masses and highlight the efficacy of levothyroxine replacement therapy in resolving both hypothyroidism and associated ovarian cysts, thereby obviating the need for surgical intervention.

Association between the oxidative balance score and thyroid function: Results from the NHANES 2007-2012 and Mendelian randomization study.

BACKGROUND: Oxidative stress is a significant contributor to the development of various diseases, and the oxidative balance score (OBS) is a valuable tool for assessing the impact of dietary and lifestyle factors on oxidative stress in humans. Nevertheless, the precise relationship between OBS and thyroid function in adults remains elusive. METHODS: This cross-sectional study comprised 6222 adult participants drawn from the National Health and Nutrition Examination Survey (NHANES) conducted from 2007 to 2012. Employing weighted multivariable linear regression modeling, the study estimated the connection between OBS quartiles and thyroid functions. The causal relationship between OBS components and thyroid function was analyzed by Mendelian randomization (MR). RESULTS: We found a significant negative correlation between OBS and free thyroxine (FT4) and total thyroxine (TT4). Univariate and multivariate MR Analyses showed a causal relationship between BMI and FT4. Copper, smoking, and riboflavin showed a causal relationship with FT4 after moderation. CONCLUSION: We found that a lifestyle high in antioxidant exposure reduced FT4 and TT4 levels in the population. We suggest that BMI, Copper, and Riboflavin are important factors in the regulation of FT4 levels.