Subclinical Hypothyroidism in Danish Lean and Obese Children and Adolescents

Metabolic Dysfunction-Associated Fatty Liver Disease (MAFLD) and Thyroid Function in Childhood Obesity: A Vicious Circle?

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a multisystem disorder characterized by the presence of fatty liver degeneration associated with excess adiposity or prediabetes/type 2 diabetes or metabolic dysregulation. An intricate relationship between the liver and thyroid has been reported in both health and disease. Simultaneously, there is a strong correlation between obesity and both MAFLD and thyroid dysfunction. In this narrative review, we highlighted the relationship between MAFLD and thyroid function in children and adolescents with obesity in order to explore how thyroid hormones (THs) act as predisposing factors in the onset, progression, and sustainability of MAFLD. THs are integral to the intricate balance of metabolic activities, ensuring energy homeostasis, and are indispensable for growth and development. Regarding liver homeostasis, THs have been suggested to interact with liver lipid homeostasis through a series of processes, including stimulating the entry of free fatty acids into the liver for esterification into triglycerides and increasing mitochondrial β-oxidation of fatty acids to impact hepatic lipid accumulation. The literature supports a correlation between MAFLD and obesity, THs and obesity, and MAFLD and THs; however, results in the pediatric population are very limited. Even though the underlying pathogenic mechanism involved in the relationship between MAFLD and thyroid function remains not fully elucidated, the role of THs as predisposing factors of MAFLD could be postulated. A potential vicious circle among these three conditions cannot be excluded. Identifying novel elements that may contribute to MAFLD could offer a practical approach to assessing children at risk of developing the condition.

Obesity is associated with subclinical hypothyroidism in the presence of thyroid autoantibodies: a cross-sectional study

BACKGROUND

Both obesity and subclinical hypothyroidism (SCH) have adverse effects on human body, but the relationship between these two conditions remains inconsistent. The presence of thyroid autoantibodies influences thyroid hormone levels, and may further mediate the interaction between obesity and SCH. This study aimed to explore the association among obesity, SCH and thyroid autoantibodies.

METHODS

This study was a cross-sectional survey of 2505 subjects. Obesity was defined as a body mass index ≥28 kg/m². Serum concentrations of thyroid hormones, thyroid peroxidase antibody (TPO-Ab) and thyroglobulin antibody (Tg-Ab) were examined. Logistic analysis was used to explore the relation among obesity, SCH and thyroid autoantibodies.

RESULTS

A proportion of 11.54% (289/2505) subjects were obese, and 165 subjects had SCH. The positive rates of thyroid autoantibodies, TPO-Ab and Tg-Ab were 17.64% (442/2505), 11.02% (276/2505) and 14.13% (354/2505), respectively. The proportion of SCH was significantly higher in obese than nonobese subjects among those with positive thyroid autoantibodies [22.41% (13/58) vs. 11.72% (45/384), p = 0.025, χ2 test]. Moreover, obesity was significantly associated with SCH in the presence of thyroid autoantibodies after adjusting for confounding factors (OR 2.212, 95% CI 1.103 to 4.433, p = 0.025). A higher proportion of subjects with obesity had Tg-Ab positivity [17.99% (52/289) vs. 13.63% (302/2216), p = 0.045, χ2 test], and obesity remained significantly associated with Tg-Ab positivity by multiple logistic analysis (OR 1.504, 95% CI 1.077 to 2.101, p = 0.017).

CONCLUSIONS

Obesity was associated with SCH in the presence of thyroid autoantibodies. Examination of SCH is recommended in obese subjects with thyroid autoantibody positivity.

Independent associations of thyroid-related hormones with hepatic steatosis and insulin resistance in euthyroid overweight/obese Chinese adults

PURPOSE

The aim of the study is to explore the independent association of free triiodothyronine (FT3), free thyroxine (FT4) and thyroid stimulating hormone (TSH) with hepatic steatosis and insulin resistance.

METHODS

A cross-sectional study of 88 overweight/obese adults who underwent anthropometric measurements [BMI, waist circumference (WC) and waist-to-height ratio (WHtR)], hepatic steatosis assessment (FibroScan) and thyroid-related hormones tests was conducted from 2018 to 2020 in Xiamen, China.

RESULTS

Subjects with increasing tertiles of FT3 showed significantly higher levels of controlled attenuation parameter (CAP) ((295.4 ± 44.1, 290.1 ± 68.2 and 331.7 ± 43.6 (dB/m) for tertile 1-3, respectively, p = 0.007) and fatty liver index (FLI) score (47.7 (33.9-60.8), 61.5 (45.1-88.9) and 90.5 (84.5-94.8), respectively, p < 0.001). FT3 significantly and positively correlated with obesity index (BMI, WC, and WHtR), homeostatic model assessment of insulin resistance (HOMA-IR) and hepatic steatosis (CAP and FLI). Multivariable linear regression analyses with adjustment for potential confounding factors showed FT3 was independently associated with BMI (regression coefficient (β (95%CI): 0.024 (0.004-0.043), p = 0.020), HOMA-IR (β (95%CI): 0.091 (0.007-0.174), p = 0.034), CAP (β (95%CI): 25.45 (2.59-48.31), p = 0.030) and FLI (β (95%CI): 0.121 (0.049-0.194), p = 0.001). Neither FT4 nor TSH was significantly associated with any indicators of obesity, insulin resistance or hepatic steatosis.

CONCLUSIONS

Increased FT3, but not FT4 or TSH, was independently associated with higher risks of hepatic steatosis and insulin resistance in euthyroid overweight/obese Chinese adults. Trial registration Registration is not applicable for our study.

Is Waist-height Ratio Associated with Thyroid Antibody Levels in Children with Obesity?

OBJECTIVE

Obesity is known to affect thyroid function. Recently, waist-height ratio (WHtR) has been considered as a useful marker of subclinical hypothyroidism in obese cases, but its relation with thyroid autoimmunity still remains unclear. We evaluated the effect of body fat mass, WHtR, and metabolic parameters on thyroid autoantibody levels in children with obesity.

METHODS

This was a cross-sectional study carried out with an obese [n=56, male/female (M/F): 29/26] and a healthy group (n=38, M/F: 19/19). All subjects underwent anthropometric measurements, laboratory investigations for thyroid function tests, thyroid peroxidase (TPO-ab) and thyroglobulin-antibodies (Tg-ab), transaminases, blood glucose, insulin levels, and lipids after overnight fasting; homeostatic model assessment for insulin resistance (HOMA-IR) was calculated for assessment of insulin resistance. Fat mass was estimated by multiple frequency bioimpedance analysis in the obese group, which was further divided into two subgroups according to the median of WHtR. All parameters were compared between the groups/subgroups.

RESULTS

In the obese group, weight, height, body mass index (BMI), free triiodothyronine, thyrotropin, TPO-ab, insulin, low density lipoprotein-cholesterol, total cholesterol, alanine aminotransferase levels, and HOMA-IR were significantly higher than the controls group (p<0.05 for all). Median of WHtR was 0.6 in the obese group. In the “WHtR >0.6” subgroup (n=28), weight, BMI, fat mass, TPO-ab, Tg-ab, insulin and triglyceride levels were higher than WHtR ≤0.6 subgroup (p<0.05). A positive correlation was obtained between Tg-ab and WHtR (rho=0.28, p=0.041).

CONCLUSION

Euthyroid children with obesity and a WHtR >0.6 are likely to have higher thyroid antibody levels, and Tg-ab levels have a positive correlation with WHtR, which reveals an association of central adiposity with thyroid autoantibody levels in these cases.

Metabolic Impact of Subclinical Hypothyroidism in Obese Children and Adolescents

OBJECTIVE

Subclinical hypothyroidism is common in children and adolescents with obesity and has been considered to be its effect with no need for treatment. Its metabolic impact has not been evaluated. Therefore the present study was conducted to determine the metabolic impact of obesity related subclinical hypothyroidism.

METHODS

Retrospective record review of obese children and adolescents between 5 and 18 y of age presenting to pediatric endocrine clinic was done. Four hundred four obese children and adolescents [251 boys, 11.8 (3.2); 5.1-18 y, BMI SDS 2.4 (0.7); 1.4-6.6] were assessed regarding thyroid functions, adiposity (clinical and DXA derived) and metabolic complications.

RESULTS

Subclinical hypothyroidism was observed in 122 (30.2%) and was associated with higher fat percentage [49.2 (5.8) vs. 47.2 (6.4) p = 0.009], android to gynoid ratio [1.1 (0.1) vs. 1.0 (0.1), p = 0.007] and alanine aminotransferase (ALT) levels [49.3 (31.5) vs. 40.8 (38.1), p = 0.04]. Subjects with subclinical hypothyroidism had 1.9 times greater odds of having non-alcoholic steatohepatitis (47.3% vs. 31.8%, p = 0.005) with no difference in the prevalence of dyslipidemia, dysglycemia or hypertension. Subclinical hypothyroidism was the only determinant of non-alcoholic steatohepatitis on binomial logistic regression (WALD = 11.04, p = 0.001) with no impact of BMI SDS, waist circumference SDS, fat percentage or android to gynoid ratio. Thyroid stimulating hormone (TSH) was the most important determinant of ALT on linear regression (B = 3.027, p < 0.005).

CONCLUSIONS

Obesity related subclinical hypothyroidism predisposes to increased ALT and non-alcoholic steatohepatitis independent of severity adiposity. The impact of thyroid supplementation in this setting needs to be explored.

Relationship of TSH Levels with Cardiometabolic Risk Factors in US Youth and Reference Percentiles for Thyroid Function

CONTEXT

Thyroid hormones play an important role in metabolic homeostasis, and higher levels have been associated with cardiometabolic risk.

OBJECTIVE

To examine the association of cardiometabolic risk factors with TSH levels in US youth.

METHODS

Cross-sectional study of youth aged 12 to 18 years without known thyroid abnormalities from 5 National Health and Nutrition Examination Survey cycles (n = 2818) representing 15.4 million US children. Subclinical hypothyroidism (SH) was defined as thyrotropin (TSH) levels of 4.5 to 10 mIU/L. Assessed cardiometabolic risk factors include abdominal obesity (waist circumference >90th percentile), hypertriglyceridemia (triglyceride ≥130 mg/dL), low high-density lipoprotein cholesterol (<40 mg/dL), elevated blood pressure (systolic and diastolic blood pressure ≥90th percentile), hyperglycemia (fasting blood glucose ≥100 mg/dL, or known diabetes), insulin resistance (homeostatic model for insulin resistance > 3.16), and elevated alanine transferase (≥ 50 for boys and ≥44 U/L for girls). Age and sex- specific percentiles for thyroid parameters were calculated.

RESULTS

In this cohort of youth (51.3% male), 31.2% had overweight/obesity. The prevalence of SH was 2.0% (95% CI 1.2-3.1). The median TSH levels were higher in youth with overweight/obesity (P < 0.001). Adjusting for age, sex, race/ethnicity, and obesity, youth with TSH in the fourth quantile had higher odds of abdominal obesity (OR 2.53 [1.43-4.46], P = .002), insulin resistance (OR 2.82 [1.42-5.57], P = .003), and ≥2 cardiometabolic risk factors (CMRF) (OR 2.20 [1.23-3.95], P = .009).

CONCLUSION

The prevalence of SH is low in US youth. The higher odds of insulin resistance and cardiometabolic risk factors in youth with TSH levels >75th percentile requires further study.

Weight loss programmes using low carbohydrate diets to control the cardiovascular risk in adolescents (Review)

Cardiovascular risk (CVR) is a broad term that includes traditional factors like hypertension, hyper lipidemia, abdominal obesity, hyperinsulinemia or overt type 2 diabetes mellitus (T2DM), and emerging ones such as hypothyroidism or inflammatory diseases. In epidemiologic studies, all of these factors are associated with atherogenesis and have complex interactions between them. They have in common an increased prevalence in the general population beginning in childhood, and are correlated with endothelial damage as demonstrated by echocardiographic modifications of the left ventricle or carotid intima-media thickness. Adolescence is a transition period where behavioural eating patterns develop and have a major impact on cardiovascular risk. To address these patterns, weight-loss programmes under medical supervision for overweight and obese adolescents are developed. It was observed that those who control the quality and quantity of their carbohydrates, by consuming more fruits and vegetables, associated with increased physical activity reduce their CVR. Some limited studies have shown that low carbohydrate diet (LCD) is safe and effective, but one should take into consideration the limited duration and the structure of the LCD. If there is a proper adherence to this type of nutritional intervention, it results in weight loss, improvement in insulin resistance, lipid profile and subclinical hypothyroidism reversal. We reviewed the literature starting from 2009 by searching all the observational, randomised clinical trials and meta-analyses on MEDLINE and SCOPUS databases regarding obesity and related metabolic diseases (dyslipidemia, type 2 diabetes, hypertension, hypothyroidism, LCD) in adolescents and synthesized the nutritional interventions for this population that could decrease CVR.

Effect of TSH on Non-Alcoholic Fatty Liver Disease (NAFLD) independent of obesity in children of predominantly Hispanic/Latino ancestry by causal mediation analysis

Background

Nonalcoholic Fatty Liver Disease (NAFLD) is a common co-morbidity of obesity. Elevated TSH levels (eTSH), also associated with obesity, may contribute to the dysmetabolic state that predisposes to NAFLD.

Objective

To assess the relationship between TSH levels and NAFLD in children with biopsy-proven NAFLD compared to controls.

Design and methods

In this retrospective study of children with biopsy-proven NAFLD and age-matched controls, the association of eTSH with NAFLD was investigated and the role of TSH as a mediator between obesity and NAFLD was assessed.

Results

Sixty-six cases and 4067 controls (69.7 vs 59% Hispanic/Latino ancestry, p = 0.1) of the same age range seen in the same time duration at an urban Children’s Hospital were studied. Children with NAFLD were more likely to be male (74.6 vs 39.4%, p < 0.001), have higher modified BMI-z scores (median 2.4 (IQR 1.7) vs 1.9 (IQR 1.7), p < 0.001), and abnormal metabolic parameters (TSH, ALT, HDL-C, non-HDL-C, and TG). Multivariate analyses controlling for age, sex and severity of obesity showed significant association between the 4^th quartile of TSH and NAFLD. Causal mediation analysis demonstrates that TSH mediates 33.8% of the effect of modified BMI-z score on NAFLD. This comprises of 16.0% (OR = 1.1, p = 0.002) caused by the indirect effect of TSH and its interaction with modified BMI-z, and 17.7% (OR = 1.1, p = 0.05) as an autonomous effect of TSH on NAFLD. Overall, 33.8% of the effect can be eliminated by removing the mediator, TSH (p = 0.001).

Conclusions

The association of eTSH and biopsy-proven NAFLD is demonstrated in children of Hispanic/Latino ancestry. Further, a causal mediation analysis implicates an effect of TSH on NAFLD, independent of obesity.

Changes in Thyroid and Glycemic Status and Food Intake in Children with Excess Weight Who Were Submitted for a Multi-Component School Intervention for 16 Months

We investigated if children with excess weight who submitted to two types of intervention at school for 16 months showed improvements in thyroid and glycemic function and food intake. Children (8-11 years) with a body mass index-for-age (BMI/A) of ≥1 Z score were divided into two groups: Treatment 1 (n = 73) involved motivation to adopt healthier lifestyle; Treatment 2 (n = 103) involved performing weekly nutritional education, motivational, and physical activities at school. A semi-quantitative food frequency questionnaire was used. The delta BMI/A were similar after 16 months; Treatment 1 showed higher decrease in thyroid-stimulating hormone (TSH; median (range)): -0.45 (-3.19 to 2.17) and 0.06 (-4.57 to 1.63) mIU/L, p = 0.001), FreeT3 (-0.46 (-2.92 to 1.54) and -0.15 (-2.46 to 1.38) pmol/L, p = 0.038), and FreeT4 -1.41 (-6.18 to 3.47) and -0.90 (-4.89 to 2.96) pmol/L, p = 0.018), followed by decrease in energy intake (7304 (6806 to 7840) and 8267 (7739 to 8832) kJ, Ptreatment = 0.439, Ptime <0.001, interaction group-time p < 0.001), macronutrients and sugar. A positive correlation between FreeT3 and BMI/A, and a negative correlation with FreeT4 and insulin were found at baseline (r 0.212, p < 0.01; r -0.155, p < 0.01, respectively) and follow-up (r 0.222, p < 0.01; r -0.221, p < 0.01). The decrease in overall diet and particularly sugar intake was accompanied by a greater reduction in TSH and FreeT3 in Treatment 1, demonstrating the impact of dietary intake on thyroid function.

Influence of subclinical hypothyroidism on metabolic parameters in obese children and adolescents

BACKGROUND

Subclinical hypothyroidism (SH) is a common condition in obese children. However, its effect on glucose and lipid metabolism in obese children remains controversial.

PURPOSE

The present study aimed to investigate the association between SH and metabolic parameters.

METHODS

A total of 215 obese children and adolescents aged 6-18 years were included in this retrospective cross-sectional study. The patients' anthropometric measurements such as thyrotropin (TSH), free thyroxine (fT4), fasting plasma glucose, and insulin levels, as well as homeostasis model assessment for insulin resistance (HOMA-IR) index, and lipid profiles were evaluated. The patients were allocated to the SH group (fT4 normal, TSH 5-10 mIU/L) (n=77) or the control group (fT4 normal, TSH<5 mIU/L) (n=138). The glucose and lipid metabolisms of the 2 groups were compared.

RESULTS

SH was identified in 77 of 215 patients (36%). Mean body mass index was similar in both groups. The mean serum insulin, HOMA-IR, and triglyceride (TG) levels were higher and the mean high-density lipoprotein cholesterol level was lower in the SH group than in the control group (P=0.007, P=0.004, P=0.01, and P=0.02, respectively). A positive correlation was observed between TSH level and insulin level, HOMA-IR, and TG level.

CONCLUSION

SH was identified in some of the obese children and adolescents. A clear association was observed between SH, insulin resistance, and dyslipidemia in obese children.

Leptin, adiponectin, and their ratio as markers of insulin resistance and cardiometabolic risk in childhood obesity

BACKGROUND

It is imperative to develop markers for risk stratification and detection of cardiometabolic comorbidities in children with obesity. The adipokines leptin and adiponectin are both involved in fat mass regulation and the development of obesity-related disorders; furthermore, their ratio (leptin/adiponectin ratio) is suggested to be associated with insulin resistance and cardiometabolic risk.

OBJECTIVE

To evaluate associations between fasting serum concentrations of the adipokines (total leptin and adiponectin as well as the L/A ratio) and cardiometabolic comorbidities in children with overweight/obesity.

METHODS

A total of 2258 children with overweight/obesity or normal weight aged 6 to 18 years were studied. Differences in anthropometrics and adipokine concentrations were tested using Wilcoxon rank-sum test. Associations between the adipokines and cardiometabolic risk were tested using Spearman's correlation and logistic regression, adjusted for age and body mass index SD score (BMI-SDS).

RESULTS

Compared to normal weight children; children with overweight/obesity exhibited higher leptin concentrations, lower adiponectin concentrations, and higher L/A ratios. After adjusting for age and degree of obesity, girls with overweight/obesity in the upper quartile range for the L/A ratio, when compared with girls in the lower quartile range, were more likely to have insulin resistance (odds ratio [OR]: 7.78 [95% confidence interval [CI], 3.78-16.65]), dysglycemia (OR: 3.08 [95% CI, 1.35-7.31]), and dyslipidemia (OR: 2.53 [95% CI, 1.18-5.59]); while boys were more likely to have insulin resistance (OR: 4.45 [95% CI, 2.03-10.10]).

CONCLUSIONS

Independent of the degree of obesity, leptin, adiponectin, and the L/A ratio were associated with insulin resistance and other cardiometabolic comorbidities in children with overweight/obesity, but the L/A ratio exhibited stronger associations than the respective adipokines.

Associations between thyroid-stimulating hormone, blood pressure and adiponectin are attenuated in children and adolescents with overweight or obesity

Background The association between thyroid-stimulating hormone (TSH) concentrations and blood pressure is well described in adults, but only studied to a limited extent in children and adolescents and almost entirely in population-based cohorts. The present study investigates the association between TSH and blood pressure, and the influence of leptin and adiponectin, in a cohort of children and adolescents enrolled in obesity treatment compared with a population-based cohort. Methods We studied 4154 children and adolescents aged 6-18 years from an obesity clinic cohort and a population-based cohort from The Danish Childhood Obesity Data- and Biobank. Anthropometrics, blood pressure and biochemical markers, including TSH, leptin and adiponectin concentrations, were collected. Adjusted correlation and interaction analyses were performed. Results Patients from the obesity clinic cohort exhibited higher concentrations of TSH and higher blood pressure than participants from the population-based cohort. TSH standard deviation scores (SDS) were significantly associated with all blood pressure-related variables in the population-based cohort, but only with systolic blood pressure SDS and hypertension in the obesity clinic cohort. The interaction between TSH SDS and adiponectin was found to be independently associated with systolic blood pressure and hypertension in the population-based cohort only. Conclusions The significant associations between TSH, adiponectin and blood pressure, observed in children and adolescents from a population-based cohort, are attenuated or absent in children and adolescents with overweight or obesity, suggesting that childhood obesity distorts the healthy interplay between the thyroid axis, thyroid-adipokine interaction and blood pressure.

The Impact of Adiposity and Puberty on Thyroid Function in Children and Adolescents

Background: In the context of a worldwide increase in childhood obesity, euthyroid hyperthyrotropinemia has been consistently reported and raises questions about its etiology, its potential metabolic complications, and its management. In this study we analyze the thyroid function with respect to BMI, pubertal status, and sex in children with obesity and discuss our results on an integrative context with the existent data from the literature. Methods: In this case-control study, we compared 389 children and adolescents with obesity to 158 controls. Age, sex, thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), BMI standard deviation score, and pubertal status were recorded. One factor-analysis of variance (ANOVA) was used with p < 0.05. Results: Mean serum TSH of children with obesity was higher (2.95 ± 1.2 mU/L) compared to normal weight group (2.42 ± 1.43 mU/L) (p < 0.0001). Only in females of both groups, serum TSH, T4, and T3 concentrations were all lower during puberty compared to prepuberty. In prepubertal girls and boys with obesity, a statistically significant correlation between TSH and BMI was found (r = 0.32, p = 0.012 and r = 0.47, p < 0.001, respectively), which is not sustained during puberty. Conclusions: Our results confirm the TSH elevation in children with obesity and indicates that puberty and adiposity have a differential sex-dependent impact on thyroid axis function.

Association between lifestyle and thyroid dysfunction: a cross-sectional epidemiologic study in the She ethnic minority group of Fujian Province in China

BACKGROUND

Thyroid dysfunction is one of the prevalent endocrine disorders. The relationship between lifestyle factors and thyroid dysfunction was not clear and some of the factors seemed paradoxical.

METHODS

We conducted this population-based study using data from 5154 She ethnic minority people who had entered into the epidemic survey of diabetes between July 2007 to September 2009. Life style information was collected using a standard questionnaire. Body mass index (BMI), Blood pressure and serum TSH, TPOAb, triglycerides (TG), total cholesterol (TC) and high-density lipoprotein cholesterol (HDL) were collected.

RESULTS

The study showed that people who drank, had higher education or suffered from insomnia have lower incidence of hyperthyroidism. On the other hand, smoking, alcohol consumption, exercise, undergoing weight watch and chronic headache were associated with decreased incidence of hypothyroidism. Using multivariable logistic regression analysis, we found that alcohol consumption was associated with decreased probability of hyperthyroidism, hypothyroidism, as well as positive TPOAb. The amounts of cigarettes smoked daily displayed a positive correlation with hyperthyroidism among smokers. Accordingly, smoking seemed to be associated with decreased risk for hypothyroidism and positive TPOAb. Exercise and maintaining a healthy weight might have a beneficial effect on thyroid health. Interestingly, daily staple amount showed an inverse correlation with incidence of positive TPOAb.

CONCLUSIONS

Within the Chinese She ethnic minority, we found associations between different lifestyle factors and the incidence of different thyroid diseases. Understanding the nature of these associations requires further investigations.

Effects of thyroid hormone and depression on common components of central obesity

Objective

We investigated the prevalence of abnormal thyroid function and depression in centrally obese participants, and to analyze the relationship of thyroid hormones and depression with components of central obesity.

Methods

We randomly selected 858 centrally obese participants and 500 non-obese controls in this study. For all participants, we measured serum free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), body mass index (BMI), waist–hip ratio (WHR), fasting blood glucose and insulin, homeostasis model assessment of insulin resistance (HOMA-IR), lipid concentrations, and blood pressure. Depression was assessed using the Center for Epidemiological Studies-Depression (CES-D) scale.

Results

Centrally obese participants had a higher prevalence of hypothyroidism and depression than non-obese controls. Serum FT4 levels negatively correlated with BMI and serum TSH levels and positively correlated with BMI, WHR, total triglycerides (TG), total cholesterol (TC), and low density lipoprotein cholesterol (LDL-C). After excluding participants with hypothyroidism and hyperthyroidism, serum FT4 levels showed negative correlation and serum TSH levels showed positive correlation with BMI in the remaining centrally obese participants. CES-D scores positively correlated with BMI.

Conclusion

We found high prevalences of hypothyroidism and depression among centrally obese participants. FT4 and TSH are important in weight regulation. Depression positively correlated with obesity.

Reference values for fasting serum concentrations of thyroid-stimulating hormone and thyroid hormones in healthy Danish/North-European white children and adolescents

Thyroid-stimulating hormone (TSH) and thyroid hormones influence the functions of many organ systems, as well as child development and growth. Several studies have reported an association between ethnicity and thyroid hormones. This study aims to explore pediatric serum concentrations of TSH, free triiodothyronine (fT3), and free thyroxine (fT4) and their relation to age and sex and subsequently to present pediatric reference intervals from healthy Danish/North-European white children. A population-based cohort in Denmark of 2411 (1435 girls) healthy school children and adolescents aged 6.0-18.9 years were included. Fasting concentrations of serum TSH, fT3, and fT4 were determined from venous blood samples using immunologic chemiluminescent assays. Age- and sex-dependent percentiles were generated using the GAMLSS function. Median values of fT3 and fT4, but not TSH, were lower in the older age group compared with the youngest age group for both sexes (all p < .05). A significant difference for fT3 was found between the sexes for all age groups (all p < .001). fT4 was negatively correlated with body mass index standard deviation scores in boys. In conclusion, serum concentrations of thyroid hormones vary during childhood and adolescence and differ with age and sex.

Waist Circumference and Subclinical Thyroid Dysfunction in a Large Cohort of Chinese Men and Women

OBJECTIVE

The association between subclinical thyroid dysfunction and waist circumference (WC) is still controversial, especially from the perspective of sex differences. We aimed to explore the impact of sex on this relationship in a large Chinese cohort.

METHODS

This cross-sectional study recruited 13,505 healthy participants (8,346 males, 5,159 females) who were enrolled in a health check program. Clinical data were collected. The association between subclinical thyroid dysfunction and WC of both sexes was analyzed separately after dividing WC into quartiles. Odds ratios (ORs) were calculated by binary logistic regression models, and linear regression analysis was also performed.

RESULTS

The prevalence rates of subclinical hyper-and hypothyroidism were significantly lower in males. Binary logistic regression models showed that WC in females with subclinical hypothyroidism had a detrimental effect with an OR of 1.011, but the effect disappeared when we included other covariates. The other ORs indicated no significant effects. The weak negative relationship between WC and thyrotropin was also indicated by linear regression analyses with very low R² values.

CONCLUSION

The current research did not show WC as a risk factor for subclinical thyroid dysfunction in either sex. Regional and ancestral origin differences may account for the variations with other studies.

ABBREVIATIONS

ALT = alanine aminotransferase; BMI = body mass index; FT3 = free triiodothyronine; FT4 = free thyroxine; TG = triglycerides; TSH = thyroid-stimulating hormone; UA = uric acid; WC = waist circumference.

The Association of Triiodothyronine-to-Thyroxine Ratio with Body Mass Index in Obese Nigerian Children and Adolescents

The interest in the relationship between thyroid dysfunction and obesity is on the increase. This study compares the triiodothyronine-to-thyroxine (T3/T4) ratio in obese and lean children and adolescents, and correlates thyroid hormones with body mass index (BMI) in obese Nigerian children. It is a retrospective study of records of 76 obese children and adolescents with a BMI of 31.7 ± 0.1 kg/m² (26 males aged 10.9 ± 0.35 years, and 50 females aged 10.8 ± 0.4 years) that were referred to the laboratory for thyroid hormone evaluation because of their obese status. The controls were 20 age-matched non-obese apparently healthy subjects, with a mean age of 11.0 ± 0.47 years and a BMI of 20.2 ± 0.2 kg/m². Serum T3, T4, and thyroid stimulating hormone (TSH) were determined using ELECSYS 1010 auto-analyzer (Roche Diagnostics, Penzberg, Germany). The BMI (p < 0.001), T3 (p < 0.01), TSH (p < 0.001) and T3/T4 ratio (p < 0.001) were significantly higher in obese than non-obese children and adolescents. Triiodothyronine (r = 0.230; p < 0.05), TSH (r = 0.272; p < 0.02), and T3/T4 ratio (r = 0.232; p < 0.05) correlated positively with BMI in obese children and adolescents. The T3/T4 ratio (p < 0.005) was significantly higher in obese boys than obese girls. Serum T3, TSH, and T3/T4 ratio correlated positive with BMI in obese Nigerian children and adolescents. Since thyroid dysfunction represents a continuum from asymptomatic to clinical symptomatic disease, it is suggested that obese children be counseled on the need to maintain ideal BMI in order to avoid the risks associated with obesity.

Subclinical hypothyroidism does not influence the metabolic and hormonal profile of women with PCOS

Background Subclinical hypothyroidism (SCH) is present in 5%-10% of polycystic ovary syndrome (PCOS) patients. To date, its impact on the metabolic and hormonal profile of those women remains controversial. The purpose of our study is to evaluate the impact of SCH on the glycemic, lipid and hormonal profile of PCOS patients. Materials and methods We conducted a prospective case control study of patients that attended the Department of Gynecological Endocrinology of our hospital. Results Overall, 280 women with PCOS were enrolled during a time period of 7 years (2009-2015). Twenty-one patients (7.5%) suffered from SCH. The anthropometric characteristics were comparable among women with PCOS and those with SCH + PCOS. The prevalence of acne, hirsutism and anovulation did not differ. Significant differences were observed in the 2-h oral glucose tolerance test (OGTT) (p = 0.003 for glucose and p = 0.046 for insulin). The QUICKI, Matsuda and homeostatic model assessment-insulin resistance (HOMA-IR) indices where, however, similar. No difference in serum lipids was observed. Slightly elevated levels of follicle stimulating hormone (FSH) and testosterone were noted. The remaining hormonal parameters remained similar among groups. Similarly, the ovarian volume and the endometrial thickness did not differ. Conclusions The impact of SCH on the metabolic and hormonal profile of PCOS patients seems to be negligible. Future studies are needed in the field and their conduct in a multi-institutional basis seems to be required, given the small prevalence of SCH among women with PCOS.