Significant Differences In TSH Levels Research Articles

Evaluation of the effect of gluten-free diet and Mediterranean diet on autoimmune system in patients with Hashimoto's thyroiditis.

Hashimoto's thyroiditis is an autoimmune disease in which thyroid cells are attacked through cell-and antibody-mediated immune processes. A gluten-free diet reduces antibody concentration and regulates thyroid autoimmunization. Mediterranean diet reduces oxidative stress. This study evaluates the short-term effects of Mediterranean, gluten-free, and Mediterranean gluten-free dietary patterns on thyroid function and autoantibody levels of patients. The 40 patients with Hashimoto's thyroiditis included in the study were randomly divided into four groups (defined as gluten-free, Mediterranean, Mediterranean gluten-free, and controls) for 12 weeks. Thyroid function tests, autoantibody levels, and food consumption were recorded at the beginning and end of the study. There was no statistically significant difference in TSH levels of the groups before the intervention, but a statistically significant difference was found afterward (p < 0.05). Free T3 hormone levels showed a statistically significant difference across the groups before and after the intervention (p < 0.05). Free T3 hormone levels increased significantly in all intervention groups after the intervention, with the highest increase in the Mediterranean group (p < 0.05). In the intervention groups, anti-TPO and anti-Tg levels decreased after the intervention; however, this difference was not significant across groups (p > 0.05). In addition, body weight, body mass index, waist and hip circumference averages decreased significantly in all intervention groups compared with controls (p < 0.05). The study achieved an increase in Free T3 hormone levels in the intervention groups. The most marked difference was seen in the Mediterranean gluten-free diet model, which may be due to the anti-inflammatory effect of both Mediterranean and gluten-free diets and the loss of body weight as a result of the intervention.

FRI488 The Effect Of Thyroid Stimulating Hormone On Brown Adipose Tissue In Humans

Abstract Disclosure: L. Salej: None. S.D. Kodani: None. N. Chaves: None. K.N. Youssef: None. R. Monahan-Earley: None. H. Halle: None. H. Shaelah: None. P. Annie: None. J.A. Parker: None. A.M. Cypess: None. G. Kolodny: None. Y. Tseng: None. B.C. James: None. A. Gavrila-Filip: None. Obesity and diabetes are two main public health concerns due to their high impact on global morbidity and mortality. In an effort to find new treatment strategies, highly active metabolic tissues such as brown adipose tissue (BAT) have been studied as potential targets. Animal studies have shown that TSH may have a direct local effect on BAT mass and activity by stimulating local T3 production via increased deiodinase-2 (DIO2) expression and also by increasing the expression of uncoupling protein-1 (UCP-1), the key molecule in BAT thermogenesis. We hypothesized that high circulating TSH levels could increase BAT activity by increasing local T3 production and generating a local tissue "thyrotoxicosis". We studied 7 patients with thyroid cancer who underwent thyroid surgery and required recombinant TSH (rhTSH) administration for standard follow-up procedures. Each patient underwent 2 PET-CT scans for assessment of BAT volume and activity, first one day after the rhTSH administration (high TSH state) and then 1-3 months later on suppressive thyroid hormone (TH) treatment (low TSH state). Indirect calorimetry and serum thyroid function tests, fasting glucose, insulin, HbA1c, and lipid panel were measured. Our results show that there was a statistically significant difference in TSH levels (p = 0.0095), with stable circulating T4 and T3 between the low and high TSH states. There was no statistically significant difference in the BAT volume and activity (SUVmax) between the high TSH and low TSH states. Age was a significant predictor of BAT SUVmax (p = 0.008; coeff = -0.39, CI = -0.65-0.13), while BMI was a significant predictor for resting energy expenditure (REE) (p = 0.04; coeff = -203.95, CI = -396.12 - -10.78). Based on these findings, along with those from our previous study[1] showing that circulating TH levels may not be directly correlated with BAT function, we have extended our study to assess the intracellular thyroid hormone status in BAT. We have collected deep peri-thyroidal adipose tissue and subcutaneous white adipose tissue (WAT) as a control group from patients undergoing thyroid surgery. In these samples, we will measure mRNA expression of TSH receptors, TH receptors, β-adrenergic receptors, DIO2 and UCP-1 and evaluate for correlations with circulating TSH and TH levels as well as different metabolic parameters to get a deeper insight into BAT function in humans. Reference: 1. Gavrila A et al. Variable Cold-Induced Brown Adipose Tissue Response to Thyroid Hormone Status. Thyroid. 2017 Jan 1;27(1):1-10. Presentation: Friday, June 16, 2023

Divergent Patterns of Thyrotropin and Other Thyroidal Parameters in Relationship with the Sex of Healthy Neonates and Infants Less than Two Years Old: A Longitudinal Study.

Background: A longitudinal study was conducted in full-term healthy infants who were born between 2015 and 2017 in Athens, Greece, to elucidate the evolution of thyrotropin (TSH) and other thyroidal parameters according to sex, from their day of birth until two years old. Other thyroidal parameters that were taken into account include antithyroid peroxidase antibody (TPO-Ab) and antithyroglobulin antibody (TG-Ab), total triiodothyronine (T3), and free triiodothyronine (fT3), along with total thyroxine (T4) and free thyroxine (fT4). Methods: Blood samples were taken at 5-day intervals from the day of birth until the 31st day of life, and then every 5th month until 2 years of age. All thyroid parameters were measured by electrochemiluminescence immunoassays. The study took place at the Iaso General, Maternity and Gynecological Clinic in Athens, Greece. Results: The sample consisted of 2916 full-term healthy neonates/infants: 1507 (51.7%) boys and 1409 (48.3%) girls. There were no significant differences in TSH levels between boys and girls in all time periods from birth up to 2 years except between 11 and 15 months of age (p = 0.038). Mean TSH levels for boys exhibited much more fluctuation and variability than for girls. In boys we found a significant association between TSH levels and fT4 (p < 0.001), while we found a significant association between TSH levels and T3 in girls (p = 0.045). Furthermore, we found that mean TPO-Ab and TG-Ab levels for boys exhibited larger variability than those for girls. Conclusions: In this study, we were able to plot the development of TSH and other thyroidal parameters by sex from birth up to two years of age. In terms of clinical practice, our findings suggest the need for a re-evaluation of the reference ranges of the studied parameters according to sex, especially in the first months of life and until the first year. Furthermore, our results suggest new optimal ranges for thyroid hormone replacement for that specific period.

Niveles de hormonas tiroideas en recién nacidos muy prematuros y prematuros extremos

Introduction: The thyroid function of the pretern infant is altered by the relative immaturity of the hypothalamus-pituitary thyroid gland axis, along with other factors such as the incidence of diseases or the use of some drugs. Currently, there is controversy over normal levels of free thyroxine (FT4) in preterm infants. Our objective was to determine the distribution of FT4 and TSH values in newborn younger than 32 weeks or 1500 g of birth weight at 15 days of chronological age, in the neonatology Neonaservice at Dr. Hernan Henriquez Aravena Hospital, Temuco. Patients and Method: Cross-sectional study; the results of FT4 and TSH from a database of 308 newborns, were analyzed, which were categorized into three gestational age ranges, 31-34, 28-30 and 23-27 weeks. It was used Pearson Chisquare for comparisons between categorical variables, and T-Test or ANOVA for categorical-variable ratios. Results: Significant differences were observed between the average values of FT4 by gestational age ranges (p = 0.000), these were 1.13 ng/dl for the range of 31 to 34 weeks, 1.03 ng/dl for the range of 28 to 30 weeks and 0.92 ng/dl for the range of 23 to 27 weeks; we did not observe significant differences in TSH levels by gestational age categories (p = 0.663). Conclusions: We established the distribution of FT4 and TSH levels in our population of very preterm and extremely preterm infants, finding differences with previous papers.

Thyroid hormone Levels in very preterm neonates and extremely preterm

The thyroid function of the pretern infant is altered by the relative immaturity of the hypothalamus-pituitary thyroid gland axis, along with other factors such as the incidence of diseases or the use of some drugs. Currently, there is controversy over normal levels of free thyroxine (FT4) in preterm infants. Our objective was to determine the distribution of FT4 and TSH values in newborn younger than 32 weeks or 1500 g of birth weight at 15 days of chronological age, in the neonatology service at Dr. Hernán Henríquez Aravena Hospital, Temuco. Cross-sectional study; the results of FT4 and TSH from a database of 308 newborns, were analyzed, which were categorized into three gestational age ranges, 31-34, 28-30 and 23-27 weeks. It was used Pearson Chi-square for comparisons between categorical variables, and T-Test or ANOVA for categorical-variable ratios. Significant differences were observed between the average values of FT4 by gestatio nal age ranges (p = 0.000), these were 1.13 ng/dl for the range of 31 to 34 weeks, 1.03 ng/dl for the range of 28 to 30 weeks and 0.92 ng/dl for the range of 23 to 27 weeks; we did not observe significant differences in TSH levels by gestational age categories (p = 0.663). We established the distribution of FT4 and TSH levels in our population of very preterm and extremely preterm infants, finding differences with previous papers.

The Metformin-Induced Changes on BMI, TSH, and Thyroid Hormones Profile of Patients with Polycystic Ovarian Syndrome

Objective: The aim of this prospective study was to investigate the effect of metformin on BMI, TSH, thyroid hormones profile, and some clinical symptoms in 32 women with PCOS. Methods: The patients received metformin at a dose of 500 mg/day which was gradually increased to 1500 mg/day and continued for 3 months. The level of BMI, TSH, T4, and T3 was measured at baseline, 3 months after treatment with metformin and 3 months after drug withdrawal. The association of metformin therapy with prevalence of constipation, hypersomnia, cold intolerance, and dry skin was also determined in these times. Results: Three months after treatment with metformin, mean BMI and TSH was significantly decreased from baseline to 28.34±2.5 kg/m2 and 2.27±0.89 μUI/ml, respectively. There was no significant difference in TSH levels before treatment and 3 months after drug withdrawal. Mean T3 and T4 levels was slightly increased during metformin therapy and significantly decreased after drug withdrawal. Treatment with metformin significantly decreased the prevalence of hypersomnia and dry skin in patients. Conclusion: The effect of metformin on TSH and thyroid hormones profile gives us an idea about the efficacy of metformin as a sole therapy or as an adjuvant in patients with PCOS and subclinical hypothyroidism, respectively.

Relationship between serum thyrotropin concentrations and metformin therapy in euthyroid patients with type 2 diabetes

A thyrotropin(TSH)-lowering effect of metformin therapy has been recently reported in patients with type 2 diabetes (T2D) and hypothyroidism. We aimed to evaluate the interplay between metformin therapy and serum TSH concentrations in a group of patients with T2D and normal thyroid function. Eight hundred and twenty-eight euthyroid patients with T2D (53% women, mean age 65·9 years, median duration of diabetes 10 years) were retrospectively evaluated. There were 250 patients on metformin treatment (30·2%). Serum concentrations of TSH were measured in all subjects. Patients on metformin treatment exhibited significantly higher TSH levels [1·63 (1·11-2·24) mU/l] than those found in patients without metformin [1·40 (1·01-2·24) mU/l, P = 0·009]. We found no significant differences in TSH levels in patients who were on therapy with other oral antidiabetics, antihypertensive drugs or hypolipidemic agents in relation to subjects not taking these drugs. Serum TSH was significantly related to gender, body mass index, hyperlipidaemia and the presence of goitre and diabetic macroangiopathy. In multiple regression analysis with TSH as dependent variable, goitre was negatively related to TSH values. Metformin therapy was a nonsignificant variable in this model. In summary, this is the first survey analysing the relationship between metformin and thyroid function in a large cohort of patients with diabetes. Our data do not support the presence of an independent and significant relationship between TSH values and metformin treatment in euthyroid patients with T2D.

Effect of Perinatal Factors on Cord Blood Thyroid Stimulating Hormone Levels

To study the influence of perinatal factors on cord blood (CB) TSH levels. In a prospective cross-sectional study, CB TSH levels were measured in 1,590 live-born infants using IRMA. The effect of various perinatal factors on the CB TSH levels was analyzed statistically. The mean TSH level in the study group was 10.6 +/- 6.7 microU/ml (range 0.01-66.4 microU/ml). A significant fall in CB TSH levels was noted with increasing gestational age. A similar decline was noted in TSH levels with increase in birth weight. No significant difference in TSH levels was noted between males and females, or AGA and SGA (n = 296) infants. Infants with birth asphyxia (Apgar score < 4 at 5 min) had significantly higher CB TSH levels (mean 31 microU/ml, n = 18) as compared to those without (mean 10.4 microU/ml) (p < 0.01). The highest TSH levels were noted in neonates delivered by forceps extraction (mean 29.4 microU/ml, n = 17) and lowest levels in infants born by elective Caesarian section (mean 8.7 microU/ml, n = 149). CB TSH levels fall with increase in gestational age while birth asphyxia and difficult deliveries tend to elevate them.

Thyrotrophin and free thyroxine trimester-specific reference intervals in a mixed ethnic pregnant population in the United Arab Emirates

Background Physiological alterations in the homeostatic control of thyroid hormones cause changes in thyroid function tests in pregnant women. A lack of method, trimester and population-specific reference intervals for free thyroxine (FT4) and thyrotrophin (TSH) makes interpretation of FT4 and TSH levels in pregnancy difficult. We established trimester-specific reference intervals for TSH and FT4 in a mixed ethnic population of pregnant women attending two antenatal clinics in the United Arab Emirates. Methods TSH and FT4 result from 1140 women with uncomplicated singleton pregnancy were available. The 95% reference intervals were determined for TSH and FT4 for each trimester for Arab women from the United Arab Emirates and other Arab countries and Asian women. Results Suppressed TSH levels in the first trimester recovered to non-pregnant levels in the third trimester. There was a significant difference in TSH levels between trimesters 1 and 2, and 2 and 3 ( p < 0.0005). There was no significant difference in the TSH levels between the various ethnic groups. Mean FT4 levels decreased with each progressive trimester in all groups. There were significant differences in FT4 levels between all three trimesters ( p < 0.005), especially between the first and second trimesters. FT4 differed significantly between UAE nationals and Asians in the first and second trimesters ( p < 0.005). Conclusions In general, the findings were in keeping with earlier reports. Use of trimester-specific reference intervals should help in the appropriate interpretation of thyroid hormone results in the mixed UAE population.

Transitory “euthyroid sick syndrome” in pre-term infants of fetal age ≤ 31 weeks

Serum T4,FT4, T3, rT3, TSH,Tg, and TBG were measured by RIA in 37 pre-term infants of postmenstrual age ≤ 31 weeks.Blood was withdrawn at day 0 and 10,20,30 and 40 days after birth.From day 10 on, 17 infants were treated with either T3 (5 μg/kg.day) or T4 (10 μg/kg.day) because of failure to thrive. The 25th,50th and 75th centile values were calculated and compared with those obtained in 20 well thriving infants. In the control group,T3 (ng/dl) at birth is low (45-81-108) increasing to (119-155-187) while rT3 (ng/dl) falls from (170-192-225) to (60-98-123).The 50th centiles of T4,FT4 and TBG remain rather stable throughout the study around birth levels at 4-5 μg I/dl,1.5 ng/dl and 2 mg/dl respectively.Patients have significantly lower levels of T4,FT4, T3 and TBG at birth and at day 10;Tg is significantly lower at birth; T3 at day 10. T3 treatment results in increased levels of T3 and TBG and lowered T4,FT4 and rT3.T4 treatment is associated with low TBG and T3 levels despite normal levels of T4, FT4 and rT3. No significant differences in TSH levels are found. These data suggest that in some pre-term infants an “euthyroid sick syndrome” might exist for some time after birth; thyroid hormone therapy might counteract failure to thrive.