Elevated Thyroid-stimulating Hormone Research Articles

Risk factors for thyroid hormone replacement therapy after hemithyroidectomy and development of a predictive nomogram

PurposeHemithyroidectomy is a valid operation to retain functional contralateral thyroid lobe that is indicated for a variety of thyroid diseases. This study aimed at determination of the risk factors for thyroid hormone replacement following hemithyroidectomy and to develop a predictive nomogram.MethodsData of patients treated by hemithyroidectomy for benign thyroid disease between January 2015 and January 2020 were retrospectively analyzed. Baseline characteristics, surgery-related variables, and preoperative and postoperative thyroid function of patients were collected from the case records and compared between patients with postoperative euthyroidism and patients with postoperative hypothyroidism. Postoperative euthyroidism patients without thyroid hormone replacement were compared to those who developed postoperative hypothyroidism with thyroid hormone replacement. The factors associated with thyroid hormone replacement were used to construct a binomial logistic-regression model and visualized as a predictive nomogram to evaluate the risk of thyroid hormone replacement following hemithyroidectomy.ResultsOf the 378 patients (74% female) included in the study, 110 (29.1%) developed postoperative hypothyroidism. Preoperative serum thyroid-stimulating hormone (TSH) > 2.172 μIU/mL was identified as an independent risk factor for postoperative hypothyroidism (odds ratio [OR] = 8.02; 95% confidence interval [CI]: 4.87–13.20; P < 0.001). Of 110 patients with postoperative hypothyroidism, 56 (50.9%) received thyroid hormone replacement. Unilateral thyroid nodule and preoperative serum TSH > 2.172 μIU/mL were independent predictors of postoperative thyroid hormone replacement (P = 0.01, and P < 0.001, respectively). Temporary subclinical hypothyroidism occurred in 12 patients; all 12 reverted to euthyroid state without thyroid hormone replacement. The discriminative effect of the binomial regression model was proved reliable by the Hosmer–Lemeshow goodness-of-fit test (P = 0.503), and predictive ability of the nomogram was satisfactory with a C-index of 0.833.ConclusionsHypothyroidism is common after hemithyroidectomy, and almost half of the patients will need thyroid hormone replacement. Elevated preoperative serum TSH level and unilateral thyroid nodule were independent predictors of thyroid hormone replacement following hemithyroidectomy. The predictive nomogram could be a useful tool for clinical practice.

Lymphocytic Thyroiditis- Association between Cytology and Biochemical Findings

Introduction: Hashimoto’s thyroiditis otherwise called as chronic lymphocytic thyroiditis is the most common cause of hypothyroidism and one of the most common thyroid lesions in Fine Needle Aspiration Cytology (FNAC). Diagnosis depends on clinical findings, ultrasonographic findings, thyroid profile and antithyroid antibody levels along with the FNAC findings. Not much studies are there which have assessed the association of the clinical and biochemical parameters with the cytological findings. Aim: To grade the cytological features of lymphocytic thyroiditis and to study the association of the grades with Thyroid Function Test (TFT) and antithyroid antibody levels. Materials and Methods: A prospective time bound analytical observational study of one year was carried out in the Department of Pathology at Government Medical College, Palakkad, Kerala, India after obtaining approval from the Institutional Ethics Committee (IEC). Out of the total of 462 cases of thyroid lesions who underwent Fine Needle Aspiration (FNA), 147 cases were lymphocytic thyroiditis as per cytology. Of these, 40 cases had Thyroid Stimulating Hormone (TSH), Antithyroglobulin Antibody (ATG) and Antithyroid Peroxidase Antibody (ATPO) levels known which were included in the study. Cytological grading of those were done and the association of the same with the above mentioned parameters was studied. Data was analysed using Statistical Package for the Social Sciences (SPSS) software. Descriptive statistics were calculated and presented as percentages, mean and Standard Deviation (SD). Chi-square test was used to find the association between the categorical variables. The p-value &lt;0.05 was taken as statistically significant. Results: Cytomorphology was diagnostic of thyroiditis in all the cases. Out of the 40 cases, 32 were females.The most common age group affected was 31-40 years, though it ranged from 18-68 years. Most common clinical presentation was diffusely enlarged thyroid, though a few presented as nodular disease. Most of the patients had grade 1 thyroiditis (23 cases) followed by grade 2 (13 cases). Elevated antithyroid antibody levels - ATPO elevated in 32 cases and ATG in 20 cases. TSH was seen elevated in 28 cases of thyroiditis. No association was observed with the antithyroid antibody levels and the cytological grade. Conclusion: Lymphocytic infiltration into the follicles is the diagnostic cytological feature of chronic lymphocytic thyroiditis. TSH elevation and positive ATPO levels strongly suggest Hashimoto’s thyroiditis. No association was found between the cytological grade and TSH and antibody levels.

Elevated thyroid-stimulating hormone is a risk factor in coronary artery bypass grafting

Elevated thyroid-stimulating hormone is a risk factor in coronary artery bypass grafting

Association between levels of thyroid-stimulating hormone and prognosis of patients admitted to intensive care units: an analysis using the MIMIC-III

To explore the association between levels of thyroid-stimulating hormone (TSH) on admission and prognosis of patients admitted to intensive care unit (ICU). The data were collected from patients who were admitted to the ICU of the Beth Israel Deaconess Medical Center in the United States from 2001 to 2012 with available TSH test records within 24 hours after the ICU admission via the Medical Information Mart for Intensive Care-III v1.4 (MIMIC-III v1.4). Information including gender, age, ethnicity, type of admission, mechanical ventilation (MV) or renal replacement therapy (RRT) received on admission, comorbidities, and TSH test records within 24 hours after the ICU admission were collected. The sequential organ failure assessment (SOFA) score, simplified acute physiology score II (SAPS II) and the comorbidities index Elixhauser (SID30) score were calculated according to the parameters. The primary outcome was hospital mortality. Differences in baseline characteristics and prognosis were examined between patients with normal TSH levels and abnormal TSH levels which was determined according to a dichotomous variable provided by the data. Multivariable Logistic regression was used to analyze the association between TSH levels and prognosis after adjusting for confounding factors. A sensitivity analysis was conducted which categorized the study population as three groups (i.e., decreased, normal, and elevated TSH levels) using the range of 0.30-3.00 mU/L as the normal range of TSH. A total of 3 425 ICU patients were enrolled in the study, of which 2 692 (78.60%) were with normal TSH and 733 (21.40%) were with abnormal TSH. There was no statistically significant difference in gender, age, ethnicity, type of admission and the ratio of MV between the normal TSH and abnormal TSH groups. Compared with normal TSH group, the patients in abnormal TSH had a higher SOFA, SAPS II and SID30 scores as well as the ratio of RRT [SOFA score: 4 (2, 7) vs. 4 (2, 6), SAPS II score: 38.02±13.76 vs. 36.53±13.75, SID30 score: 11 (4, 22) vs. 11 (0, 20), RRT ratio: 5.32% (39/733) vs. 3.49% (94/2 692), all P < 0.05]. The hospital mortality of patients in normal TSH was significantly higher than that of those in abnormal TSH [9.82% (72/733) vs. 5.94% (160/2 692), P < 0.01]. After adjusting for confounding factors, abnormal TSH was significantly associated with hospital mortality [odds ratio (OR) = 1.71, 95% confidence interval (95%CI) was 1.24-2.35, P = 0.001]. In the sensitivity analysis in which the range of 0.30-3.00 mU/L was used as the normal range of TSH, compared with normal TSH, decreased TSH (OR = 2.36, 95%CI was 1.40-3.97, P = 0.001) and elevated TSH (OR = 1.44, 95%CI was 1.05-1.98, P = 0.023) were both significantly associated with increased hospital mortality. An abnormal level of TSH within 24 hours after admitted to ICU is an independent risk factor for hospital mortality among ICU patients.

Acute effects of a typical rhythmic gymnastic training session on physiological parameters in Olympic athletes

The aim of this study was to evaluate the effects of a day with two separate training sessions (morning and afternoon) of rhythmic gymnastics on erythrocytes, leukocytes, muscle damage, oxidative stress, and hydration of Brazilian team [age 17.7 (±1.1) years; body height 165 (±0.5) cm; body mass 49.7 (±4.2) kg]. Heart rate and session-ratings of perceived exertion were used to monitor training intensity. Blood samples were collected immediately before (M1) and after (M2) the training day for analyzing erythrocytes, leukocytes, plasma creatine kinase activity, lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, ferric reducing ability plasma, thyroid-stimulating hormone, and free T4. Saliva was collected for cortisol analysis. After 24 hours rest (M3), blood collection was performed to analyze creatine kinase and lactate dehydrogenase. The moderate-intensity training day induced significant elevations of total leukocytes (5,163.3 to 9,617.8), lymphocytes (1,752.7 to 2,729.7), neutrophils (2,873.9 to 6,163.6), monocytes (255.7 to 519.1), platelets (280,000.0 to 300,666.7), aspartate aminotransferase (13.1 to 25.6), lactate dehydrogenase (102.5 to 249.1), thyroid-stimulating hormone (1.0 to 3.2), and ferric reducing ability plasma (136.8 to 165.4), as well as significant reductions in red cells (4,691,111.1 to 4,497,777.8), hematocrit (42.1 to 39.3), and hemoglobin (12.9 to 12.5) at M2. There were also significant increases in creatine kinase (144.2 to 519.3) and lactate dehydrogenase (102.5 to 538.2) at M3. The average dehydration rate was 1.3%. A moderate-intensity day of training in rhythmic gymnastics of 8h21min duration caused hemolysis, leukocytosis, muscle damage, redox status perturbations, and insufficient hydration status. These findings show that athletes are exposed to physiological vulnerabilities that can possibly harm their performance and health.

Mother's iodine exposure and infants' hypothyroidism: the Japan Environment and Children's Study (JECS).

In this study, we aimed to determine the association of neonatal/post-neonatal hypothyroidism with mother's iodine exposure, especially povidone iodine disinfection, and hysterosalpingography. Participants were mother-child pairs in a Japanese birth cohort (n = 100,286). Risk factors of hypothyroidism were supplement intake, seaweed intake, other daily iodine intake, povidone iodine disinfection at delivery, and maternal history of hysterosalpingography, thyroid disease (Graves' disease and Hashimoto's thyroiditis), and medication (thiamazole and levothyroxine). Congenital hypothyroidism (CH) at age 1 year was assessed using a questionnaire. Transient hypothyroidism was defined as elevated thyroid stimulating hormone level at birth and absence of CH at age 1 year. The incidence of CH at age 1 year per 100 children was 1.1 for those born at 22-30 weeks' gestation, 0.17 following povidone iodine disinfection, and 0.07, 0.95, 0.81, 1.17, and 1.15 with a maternal history of hysterosalpingography, Graves' disease, Hashimoto's thyroiditis, thiamazole use, and levothyroxine use, respectively. Odds ratios (95% confidence intervals) of CH at age 1 year for povidone iodine disinfection, hysterosalpingography history, maternal Graves' disease, and maternal Hashimoto's thyroiditis were 1.13 (0.71-1.79), 0.47 (0.07-3.36), 7.06 (3.70-13.5), and 5.93 (2.90-12.1), respectively. For transient hypothyroidism for povidone iodine disinfection and hysterosalpingography history, these values were 1.99 (1.51-2.62) and 0.63 (0.20-1.96), respectively. Maternal thyroid disease greatly increased neonatal/post-neonatal hypothyroidism risk. Povidone iodine disinfection may increase transient hypothyroidism risk but not the risk at 1 year of age. Hysterosalpingography does not increase hypothyroidism risk from birth to age 1 year.

Investigation of pituitary functions after acute coronavirus disease 2019.

Although coronavirus disease 2019 (COVID-19) mainly involves the lungs, it also affects many systems. The hypothalamic/pituitary axis is vulnerable to hypoxia, hypercoagulation, endothelial dysfunction and autoimmune changes induced by COVID-19 infection. Given that there is no extensive investigation on this issue, we investigated the pituitary functions three to seven months after acute COVID-19 infection. Forty-three patients after diagnosis of COVID-19 infection and 11 healthy volunteers were included in the study. In addition to the basal pituitary hormone levels, growth hormone (GH) and hypothalamo-pituitary adrenal (HPA) axes were evaluated by glucagon stimulation test (GST) and low-dose adrenocorticotropic hormone (ACTH) stimulation test, respectively. The peak cortisol responses to low-dose ACTH test were insufficient in seven (16.2%) patients. Twenty (46.5%) and four (9.3%) patients had inadequate GH and cortisol responses to GST, respectively. Serum insulin-like growth factor-1 (IGF-1) values were also lower than age and sex-matched references in four (9.3%) patients. The peak GH responses to GST were lower in the patient group when compared to the control group. Other abnormalities were mild thyroid-stimulating hormone elevation in four (9.3%) patients, mild prolactin elevation in two (4.6%) patients and central hypogonadism in four (9.3%) patients. Mean total testosterone values were lower in male patients when compared to male controls; however, the difference was not significant. These findings suggest that COVID-19 infection may affect pituitary functions, particularly the HPA and GH axes. These insufficiencies should be kept in mind in post-COVID follow-up. Long-term data are needed to determine whether these deficiencies are permanent or not.

Serum Thyrotropin Elevation and Coronary Artery Calcification in Hemodialysis Patients

Introduction: Hypothyroidism is highly prevalent in end-stage kidney disease patients, and emerging data show that lower circulating thyroid hormone levels lead to downregulation of vascular calcification inhibitors and coronary artery calcification (CAC) in this population. To date, no studies have examined the association of serum thyrotropin (TSH), the most sensitive and specific single biochemical metric of thyroid function, with CAC risk in hemodialysis patients. Methods: In secondary analyses of patients from the Anti-Inflammatory and Anti-Oxidative Nutrition in Hypoalbuminemic Dialysis Patients trial, we examined serum TSH levels and CAC risk assessed by cardiac computed tomography scans collected within a 90-day period. We evaluated the relationship between serum TSH with CAC Volume (VS) and Agatston score (AS) (defined as >100 mm³ and >100 Houndsfield Units, respectively) using multivariable logistic regression. Results: Among 104 patients who met eligibility criteria, higher TSH levels in the highest tertile were associated with moderately elevated CAC VS and AS in case-mix-adjusted analyses (ref: lowest tertile): adjusted ORs (95% CIs) 4.26 (1.18, 15.40) and 5.53 (1.44, 21.30), respectively. TSH levels >3.0 mIU/L (ref: ≤3.0 mIU/L) were also associated with moderately elevated CAC VS and AS. In secondary analyses, point estimates of incrementally lower direct free thyroxine levels trended toward elevated CAC VS and AS, although associations did not achieve statistical significance. Conclusions: In hemodialysis patients, higher serum TSH was associated with elevated CAC VS and AS. Further studies are needed to determine if thyroid hormone supplementation can attenuate CAC burden in this population.

Characterization of stirred yoghurt enriched with probiotics and beetroot and its therapeutic potential in experimental type 2 diabetes.

Type-2 diabetes is the most prevalent metabolic disease, which calls for researchers to find many natural products that are effective in fighting diabetes and its complications. Stirred yoghurt samples were prepared, enriched with probiotics, and fortified with either 1% or 2% of the fine powder of beetroots. The chemical, physical, sensorial, and microbial properties of the yoghurt samples were studied over a 15-day storage period. The total phenolic compounds, flavonoids, antioxidant activity as well as the reducing power of the dried beetroot and the yoghurt samples were assessed.The prepared yoghurt samples were evaluated in type 2 diabetic rats. Fortification with beetroot led to an increase of the total phenolic compounds, antioxidant activity, and the probiotic counts in the prepared yoghurt. The intervention with the prepared yoghurt samples resulted in an increase in the number of beneficial bacteria in diabetic rats&rsquo; feces, hypoglycemic effect, and suppression in the elevation of C-reactive protein (CRP) and thyroid stimulating hormone (TSH). This study suggests that stirred yoghurt enriched with probiotics and fortified with beetroot have therapeutic potential for type 2 diabetes.

Characterization of stirred yoghurt enriched with probiotics and beetroot and its therapeutic potential in experimental type 2 diabetes [pdf

BACKGROUND Type-2 diabetes is the most prevalent metabolic disease, which calls for researchers to find many natural products that are effective in fighting diabetes and its complications. METHODS Stirred yoghurt samples were prepared, enriched with probiotics, and fortified with either 1% or 2% of the fine powder of beetroots. The chemical, physical, sensorial, and microbial properties of the yoghurt samples were studied over a 15-day storage period. The total phenolic compounds, flavonoids, antioxidant activity as well as the reducing power of the dried beetroot and the yoghurt samples were assessed.The prepared yoghurt samples were evaluated in type 2 diabetic rats. RESULTS Fortification with beetroot led to an increase of the total phenolic compounds, antioxidant activity, and the probiotic counts in the prepared yoghurt. The intervention with the prepared yoghurt samples resulted in an increase in the number of beneficial bacteria in diabetic rats’ feces, hypoglycemic effect, and suppression in the elevation of C-reactive protein (CRP) and thyroid stimulating hormone (TSH). CONCLUSIONS This study suggests that stirred yoghurt enriched with probiotics and fortified with beetroot have therapeutic potential for type 2 diabetes.

Oxcarbazepine was associated with risks of newly developed hypothyroxinaemia and impaired central set point of thyroid homeostasis in schizophrenia patients.

Hypothyroxinaemia might be easily ignored, because attention is typically paid to individuals with elevated thyroid stimulating hormone (TSH). In this study, we aimed to evaluate the association of oxcarbazepine use as adjuvant for treatment of schizophrenia with hypothyroxinaemia and central set point of thyroid homeostasis. This retrospective cohort study was conducted in the Second Affiliated Hospital of Xinxiang Medical University. Inpatients with a diagnosis of schizophrenia admitted between January 2016 and October 2019 with normal thyroid function at admission were included. Oxcarbazepine use was the exposure measure. Newly developed hypothyroxinaemia was the primary outcome measure and parameters of thyroid homeostasis central set point as measured by TSH index and thyroid feedback quantile-based index (TFQI) were the secondary outcome measures. In total, 1207 eligible patients were included. The occurrence of hypothyroxinaemia in patients who received oxcarbazepine was higher (35/107, 32.7%) than in those patients who did not (152/1099, 13.8%), with adjusted relative risk of 2.24 and 95% confidence interval of 1.57 and 3.17. Oxcarbazepine use was associated with greater reduction in TSH index (adjusted β-0.33 and 95% confidence interval -0.48, -0.19) and TFQI (adjusted β-0.24 and 95% confidence interval -0.31, -0.16). Oxcarbazepine use was independently associated with increased risk of developing hypothyroxinaemia, and greater reduction in TSH index and TFQI, suggesting that impaired central set point of thyroid homeostasis might be involved in the mechanism of oxcarbazepine-induced hypothyroxinaemia.

The Many Faces of Elevated TSH: When to Avoid Thyroid Hormone Therapy in Older Adults

We have previously demonstrated that hypothalamic-pituitary-thyroid axis aging is characterized by several distinct patterns. An elevated thyrotropin (TSH) level (mean 5.6mIU/L) with normal free thyroxine (FT4) was present in 75 BLSA participants with at least 3 visits. Twenty-one percent had an historical pattern consistent with primary gland failure, while 13% had a pattern consistent with an HPT response to stressors (aging-adaptation). The remainder had intermediate patterns of change. FT4 >0.92pg/ml identified those in whom TSH elevations occurred with aging-adaptation with a 90.0% sensitivity and 93.8% specificity, indicating no need for therapy. In addition, among 597 participants with stable TSH levels in the reference range, being on thyroid hormone therapy increased mortality risk (IRR=1.8; 95% CI 0.9-2.1). Thus, including FT4 in the diagnostic criteria for hypothyroidism in older adults could target therapy to avoid the potential harm of reversing the aging adaptations in those who do not have true early hypothyroidism.

Clinical Course of Early Postoperative Hypothyroidism Following Thyroid Lobectomy in Pediatrics.

Introduction: Thyroid lobectomy reduces risks of surgical complications and need for levothyroxine (LT4). We aimed at identifying the clinical course and risk factors for postlobectomy hypothyroidism to optimize surgical counseling and management in pediatric patients undergoing lobectomy. Methods: Clinical and biochemical presentations pre- and postlobectomy were retrospectively reviewed for 110 patients who underwent thyroid lobectomy between 2008 and 2020 at the Children's Hospital of Philadelphia. Results: Approximately 28.2% of patients (31/110) developed postlobectomy hypothyroidism defined by an elevated thyrotropin (TSH) level, including 24.5% (27/110) with subclinical hypothyroidism (TSH >4.5 and <10.0 mIU/L) and 3.6% (4/110) with overt hypothyroidism (TSH >10.0 mIU/L). LT4 was initiated in 12.7% (14/110) of cases. Most patients (81.6%; 84/103) recovered euthyroidism within 12 months postlobectomy. When excluding patients with autonomous nodule(s), median preoperative TSH was 1.09 (interquartile range [IQR] = 0.70-1.77) mIU/L and 1.80 (IQR = 1.02-2.68) mIU/L in euthyroid and hypothyroid patients, respectively, with multivariate logistic regression confirming the association between an increased preoperative TSH and postlobectomy hypothyroidism (odds ratio = 1.8 [confidence interval 1.08-3.13], p = 0.024). Of the patients who underwent thyroid lobectomy and developed postoperative hypothyroidism (n = 31), 38.7% (12/31) had a preoperative diagnosis of an autonomously functioning thyroid nodule. Conclusions: Thyroid function should be evaluated postlobectomy to assess the need for LT4. LT4 should be considered if the TSH remains elevated, especially if an upward trend is observed or TSH is >10.0 mIU/L. Suppressed preoperative TSH associated with autonomous nodules is an independent risk factor for postlobectomy hypothyroidism.

Sunitinib-Induced Hypothyroidism and Survival in Pancreatic Neuroendocrine Tumors

AbstractSunitinib has been approved for the treatment of pancreatic neuroendocrine tumors, renal-cell carcinoma, and gastrointestinal stromal tumors. The elevation of thyroid-stimulating hormone serum levels is a common side effect. Studies suggest a correlation between sunitinib-induced hypothyroidism and treatment outcome in patients with renal-cell carcinoma and gastrointestinal stromal tumors. This study assessed whether sunitinib-induced hypothyroidism is a predictive marker of the objective response rate, progression-free survival, and overall survival in pancreatic neuroendocrine tumor patients. Twenty-nine patients treated with sunitinib for advanced pancreatic neuroendocrine tumors were included. The incidence of sunitinib-induced hypothyroidism was 33%. The median progression-free survival of patients who developed hypothyroidism was 16 months (95% confidence interval: 6.2–25.8 months) as compared with six months among euthyroid patients (95% confidence interval: 0.1–12.2 months) (p=0.02). The median overall survival was 77 months (95% confidence interval: 31.4–122.6 months) in hypothyroid patients but 12 months (95% confidence interval: 5.9–18.1 months) in subjects with euthyroidism (p=0.001). The median overall survival from the time of initial diagnosis ranged from 247 months in patients with hypothyroidism to 65 months in euthyroid subjects (p=0.015). Elevated thyroid-stimulating hormone levels are a prognostic biomarker of improved outcomes of sunitinib therapy in pancreatic neuroendocrine tumor patients.

Postpartum Thyroid Dysfunction in Women With Known and Newly Diagnosed Hypothyroidism in Early Pregnancy.

BackgroundHypothyroidism in the first trimester of pregnancy (T1) has great adverse effects on mothers and foetuses. However, few studies have investigated the influence on postpartum thyroid dysfunction. This study aimed to evaluate their long-term effect on postpartum thyroid function within one year after delivery.MethodsIn total, 151 women were recruited from 1496 participants and were classified as newly diagnosed subclinical hypothyroidism (SCH) in T1 (ND-SCH, n=50), previously known SCH before pregnancy (PK-SCH, n=51) and previously known overt hypothyroidism (PK-OH, n=50). Their thyroid functions were dynamically monitored from pre-conception to one-year postpartum.ResultsDuring pregnancy, the first thyroid functions’ test time in T1 were 5-8 gestational weeks. After delivery, the prevalence of postpartum thyroiditis (PPT) was comparable in women with previously known and newly diagnosed hypothyroidism [ND-SCH 62.0% vs PK-SCH 64.7% vs PK-OH 64.0%, P=0.96]. For the ND-SCH group, PPT was significantly related with thyroid-stimulating hormone (TSH) >4.0 mU/L occurring at <8 gestational weeks [OR=8.06, 95% CI, 2.08-31.29] and TSH levels outside 1.0-2.5 mU/L near childbirth [OR=3.73, 95% CI, 1.04-13.41]. For patients with known hypothyroidism before pregnancy (PK-SCH and PK-OH), TSH>2.5 mU/L in T1 [OR=3.55, 95% CI, 1.43-8.81] and TPOAb≥300 μIU/mL [OR=6.58, 95% CI, 2.05-21.12] were associated with PPT. Regardless of whether SCH was diagnosed before pregnancy or in T1, the levothyroxine (LT4) treatment was discontinued at delivery. More than 50% of the patients had to face the hypothyroidism phase of postpartum and restarted LT4 treatment in the first-year follow-up. The logistic regression analysis revealed that TSH elevation occurring at <8 gestational weeks [OR=2.48, 95% CI, 1.09-5.6], TSH levels outside 1.0-2.5 mU/L near childbirth [OR=3.42, 95% CI, 1.45-8.05], and TPOAb≥300 μIU/mL [OR=6.59, 95% CI, 1.79-24.30] were the risk factors.ConclusionTSH elevation at <8 gestational weeks was associated with PPT after delivery in women with known and newly diagnosed hypothyroidism. Especially for SCH patients who stopped LT4 treatment at delivery, unsatisfactory TSH level at <8 gestational weeks and near childbirth, TPOAb≥300 μIU/mL were the risk factors for LT4 retreatment in one-year postpartum.

Treating hypothyroidism is not always easy: When to treat subclinical hypothyroidism, TSH goals in the elderly, and alternatives to levothyroxine monotherapy.

The majority of patients with hypothyroidism feel better when levothyroxine treatment restores thyroid-stimulating hormone (TSH) concentrations to normal. Increasingly, a significant minority of patients remain symptomatic and are dissatisfied with their treatment. Overzealous treatment of symptomatic patients with subclinical hypothyroidism may contribute to dissatisfaction among hypothyroidism patients, as potential hypothyroid symptoms in patients with minimal hypothyroidism rarely respond to treatment. Thyroid hormone prescriptions have increased by 30% in the United States in the last decade. The diagnosis of subclinical hypothyroidism should be confirmed by repeat thyroid function tests ideally obtained at least 2months later, as 62% of elevated TSH levels may revert to normal spontaneously. Generally, treatment is not necessary unless the TSH exceeds 7.0-10mIU/L. In double-blinded randomized controlled trials, treatment does not improve symptoms or cognitive function if the TSH is less than 10mIU/L. While cardiovascular events may be reduced in patients under age 65 with subclinical hypothyroidism who are treated with levothyroxine, treatment may be harmful in elderly patients with subclinical hypothyroidism. TSH goals are age dependent, with a 97.5percentile (upper limit of normal) of 3.6mIU/L for patients under age 40, and 7.5mIU/L for patients over age 80. In some hypothyroid patients who are dissatisfied with treatment, especially those with a polymorphism in type 2 deiodinase, combined treatment with levothyroxine and liothyronine may be preferred.

Thyroid Disorders.

Thyroid Disorders.

Age-dependent response to T4 overtreatment and recovery on systemic and organ level.

Thyroid hormone (TH) metabolism and cellular TH action are influenced by ageing. To investigate the response to thyroxine (T4) overtreatment, a kinetic study was conducted in young and aged mice with chronic hyperthyroidism and hormone withdrawal. Five and 22 months old male mice were treated with T4 or PBS over 5 weeks, followed by observation for up to 12 days. Serial analysis was performed for thyroid function parameters, transcript levels of TH target genes, deiodinase type 1 (DIO1) activity as well as serum lipids at 12, 24, 72, 144, 216, and 288 h after cessation of T4 administration. Higher FT3 concentrations and higher renal DIO1 activities were noted in aged mice 12 h after T4 withdrawal and marked thyroid-stimulating hormone elevation was found in aged mice after 12 days compared to respective controls. A biphasic expression pattern occurred for TH target genes in all organs and a hypothyroid organ state was observed at the end of the study, despite normalization of TH serum concentrations after 72 h. In line with this, mirror-image kinetics were detected for serum cholesterol and triglycerides in aged and young mice. Recovery from TH overtreatment in mice involves short- and medium-term adaption of TH metabolism on systemic and organ levels. Increased renal DIO1 activity may contribute to higher T3 concentrations and prolonged thyrotoxicosis followed by hypothyroidism in an aged-mouse organism. Translation of these findings in the clinical setting seems warranted and may lead to better management of hyperthyroidism and prevention of T4 overtreatment in aged patients.

Changes of Structural and Functional Attention Control Networks in Subclinical Hypothyroidism

Objective: This study aimed to explore the structural changes in patients with subclinical hypothyroidism (SCH) using voxel-based morphometry (VBM) and to investigate the altered attentional control networks using functional MRI (fMRI) during the performance of a modified Stroop task with Chinese characters.Methods: High-resolution three-dimensional (3D) T1-weighted images and an fMRI scan were taken from 18 patients with SCH and 18 matched control subjects. The Montreal Cognitive Assessment Chinese-revised (MoCA-CR) and the Stroop task were used to evaluate the cognitive and attention control of the participants.Results: Compared to controls, the VBM results showed decreased gray matter volumes (GMVs) in bilateral prefrontal cortices (PFCs, including middle, medial, and inferior frontal gyri), cingulate gyrus, precuneus, left middle temporal gyrus, and insula in patients with SCH. The fMRI results showed a distributed network of brain regions in both groups, consisting of PFCs (including superior and middle and inferior frontal cortices), anterior cingulate cortex (ACC), posterior cingulate cortex, and precuneus, as well as the insula and caudate nucleus. Compared to controls, the SCH group had lower activation of the above brain areas, especially during the color-naming task. In addition, the normalized GMV (nGMV) was negatively correlated with thyroid-stimulating hormone (TSH) level (r = −0.722, p < 0.001).Conclusion: Results indicate that patients with SCH exhibit reduced GMVs, altered BOLD signals, and activation in regions associated with attention control, which further suggest that patients with SCH may have attentional control deficiency, and the weakened PFC–ACC–precuneus brain network might be one of the neural mechanisms. Negative correlations between nGMV and TSH suggest that TSH elevation may induce abnormalities in the cortex.

Indicators of cognitive activity of children with laboratory hypothyroidism

The growth rate of a healthy child, the peculiarities of its physical and intellectual development, the formation of reproductive function are largely determined by the state of the endocrine system. Thyroid hormones have a significant impact on the growth and development of the child's organism. Today, attention is focused on the consequences of intellectual disabilities in children with hypothyroidism, as well as the impact of chronic iodine deficiency in the environment on the development of children. Insufficient intake of iodine in the body leads to congenital dysontogenesis of higher mental functions, to the formation, in severe cases, of mental retardation of varying degrees, and, in mild forms - to the borderline or partial disorders of intelligence.&#x0D; The aim is to study the cognitive functions of children with laboratory hypothyroidism.&#x0D; Methods. For a screening study of the intellectual development of school-age children living in geographical areas of Chernivtsi region (Ukraine) with varying degrees of iodine supply, 399 schoolchildren aged 11-18 years were studied, including 194 boys and 205 girls. The main group consisted of children (99) with laboratory hypothyroidism (HL), with thyroid stimulating hormone (TSH) elevation or with diverse complaints and who had been found to have elevated TSH levels during routine examinations. Patients with any kind of systemic disease and/or taking medications were excluded from the study. Diagnosis of HL was based on mild increase of TSH (5-25mIU/L) with a normal fT4 level. Thyrotropin-releasing hormone (TRH) test was also performed in all children. TSH response to TRH stimulation was considered to be normal when TSH levels were between 5-25 mIU/L. The formation of intellectual function was determined using a fragment of the R. Kettel test (adapted modified version of the children's personality questionnaire R. Kettel).&#x0D; Іnclusion сriteria: age 11-18 years, living in the Chernivtsi region, the absence of organic pathology of the CNS and mental retardation, diseases of the eyesight and hearing, for 6 months, all subjects did not receive any treatment with iodine-containing drugs and thyroid hormones.&#x0D; Results. Analysis of the study results showed that children, for the most part, have an average degree of intellectual development (60%). The level of intellectual formation changed in the direction of decreasing with increasing degree of iodine deficiency. Among children with laboratory hypothyroidism, the number of those who had a low level of intelligence was almost twice as high as in children from the comparison group 25 [21.8-27.3] % against 13 [11.8-16.6] %, P &lt; 0.01). Children with laboratory hypothyroidism have a "debt" of 56% of attention, 36% of perception, 26% of motility, and 44% of memory. The pace of operating activities was reduced by 26%. Comparison of TSH concentration, ioduria and thyroid volume with the presence or absence of deficits in certain cognitive functions showed that in children with laboratory hypothyroidism and fine motor skills TSH G level was increased by 90%, thyroid volume by 28% , and with memory loss - 125% and 38%, respectively. Correlative analysis revealed a highly probable positive relationship between moderate strength in prepubertal children between thyroid volume and fine motor skills (r = 0.485, P &lt; 0.01), memory (r = 0.488, P &lt; 0.05) and efficiency (r = 0,321, P &lt; 0,05).&#x0D; Conclusion. Children with subclinical hypothyroidism are characterized by decreased memory, instability of attention and decreased ability to concentrate, impaired fine motor skills, which generally reduces their mental capacity.