Thyroid hormone levels and BMI-SDS changes in adolescents with obesity

Background

Thyroid hormones play an important role in energy metabolism and weight control, explained mostly by inducing thermogenesis and increasing basal metabolic rate. It has recently been shown that FT4 levels are associated with food preferences, which might also play a role in modulating body weight. The aim of this longitudinal follow-up study was to analyze the relationship of thyroid hormones levels (FT4, TSH) at baseline with weight/BMI-SDS changes in children and adolescents with obesity.

Methods

Three hundred seventy-seven children and adolescents have been enrolled to this study and followed up without a systematic intervention program for 5.59 ± 1.85months. Children and adolescents were divided into three subgroups: 1) 144 adolescents with obesity (15-19 years), 2) 213 children with obesity (10-14.9 years), and 3) 20 lean adolescents (15-19 years). Thyroid hormones were measured at the baseline, and anthropometry was performed at the baseline and during the follow-up. For further analyses, participants were divided according to the BMI-SDS change into two groups: 1. with BMI-SDS decrease, and 2. with BMI-SDS increase.

Results

Adolescents with obesity from the BMI-SDS decrease group had significantly lower baseline serum levels of TSH compared to the BMI-SDS increase group (2.4 ± 1.0 vs. 3.2 ± 2.0mIU/l; p=0.005). Similar difference was found for FT4 levels (14.7 ± 2.2 in the BMI-SDS decrease group vs. 15.5 ± 2.7pmol/l in the BMI-SDS increase group, p=0.048). Moreover, the BMI-SDS decrease was present in significantly higher percentage of adolescents with obesity with lower than median TSH level compared to those with higher than median TSH level at baseline (61.1% vs 38.6%, p=0.011). Likewise, the BMI-SDS decrease was present in significantly higher percentage of adolescent females with obesity and lower than median FT4 compared to those with higher than median FT4 level at baseline (70.6% vs. 23.5%, p<0.001). No associations of baseline thyroid hormones with the BMI-SDS change were observed in children with obesity or lean adolescents.

Conclusion

Adolescents with obesity and increased BMI-SDS during the follow-up had significantly higher baseline levels of both TSH and FT4 compared to BMI-SDS decrease group. These results support the previous findings that higher FT4 in individuals with obesity may influence weight gain.

Food preferences and thyroid hormones in children and adolescents with obesity

BACKGROUND

Thyroid hormones profoundly affect energy metabolism but their interrelation with food preference, which might contribute to childhood obesity development, are much less understood. In this study, we investigated if thyroid hormone levels are associated with specific modulation of food preference and potentially linked to the level of obesity in children and adolescents.

METHODS

Interrelations between food preference and peripheral thyroid activity were examined in a population of 99 non-obese and 101 obese children and adolescents (12.8 ± 3.6 years of age, 111/89 F/M) randomly selected from the patients of the Obesity and Metabolic Disease Out-patient Research Unit at National Institute for Children's Diseases in Bratislava in a period between December 2017 and March 2020.

RESULTS

Children and adolescents with obesity had a lower preference for food rich in high sucrose and high-complex carbohydrates, while the preference for protein and fat-containing food and that for dietary fibers did not differ between obese and nonobese. In adolescents with obesity, free thyroxine (FT4) correlated positively with the preference for a high protein and high fat-rich diet, irrespective of the fatty acid unsaturation level. Moreover, FT4 correlated negatively with the preference for dietary fibers, which has been also exclusively found in obese adolescents. Individuals with obesity with higher FT4 levels had higher systemic levels of AST and ALT than the population with lower FT4. Multiple regression analysis with age, sex, BMI-SDS, and FT4 as covariates revealed that FT4 and male gender are the major predictors of variability in the preference for a diet high in protein, fat, and monounsaturated fatty acids. FT4 was the sole predictor of the preference for a diet containing saturated and polyunsaturated fatty acids as well as for a diet low in fiber.

CONCLUSION

The link between free thyroxin levels and dietary preference for food rich in fat and protein is present exclusively in individuals with obesity. Higher serum FT4 was linked with elevated AST and ALT in children and adolescents with obesity, and FT4 was the best predictor for preference for food rich in fat and low in fiber. This may indicate that FT4 could contribute to the development of childhood obesity and its complications by modulating food preference.

Primary lymphoma of the pancreas – a case report

Súhrn: Bolesti brucha patria medzi pomerne časté symptómy u adolescentov. Príčiny, ktoré sa podieľajú na bolestiach brucha, sú pestré a tým aj diferenciálna dia­gnostika je pomerne rozsiahla a zložitá. To súvisí pravdepodobne s tým, že brucho zaberá pomerne veľkú oblasť, obsahuje množstvo orgánov, štruktúr, systémov vrátane lymfatických uzlín, ktoré generalizovane reagujú na infekciu, či nádorové ochorenia. V našej kazuistike opisujeme prípad 17-ročného pacienta s náhlymi bolesťami brucha, chudnutím, vracaním a ikterom. V rámci diferenciálnej dia­gnostiky sa realizovali laboratórne a zobrazovacie vyšetrenia so zameraním na pankreas a hepatobiliárny trakt, kde sa zobrazila zväčšená hlava a chvost pankreasu, peripankreatická lymfadenopatia s vedľajším nálezom drobných ložísk na obličkách. V úvode sa suponovala skôr hereditárna pankreatitída a pseudotumory na obličkách, vzhľadom na vek pacienta bol menej pravdepodobný tumor pankreasu a metastázy. Definitívna dia­gnóza bola stanovená odberom bio­ptických vzoriek pankreasu pomocou endosonografického vyšetrenia. Histologický a cytologický nález preukázal prítomnosť lymfocytárnych blastických buniek, charakteru CD20+ B-NHL, konštatovaný difúzny veľkobunkový B-lymfóm pankreasu (DLBCL – diffuse large B cell lymphoma). Staging ochorenia nepreukázal inflitráciu malígnych buniek v kostnej dreni a centrálnej nervovej sústave. Promptne stanovená dia­gnóza a podaná príslušná onkologická liečba (chemoterapia v kombinácii s monoklonálnou protilátkou) zabezpečila pacientovi návrat do každodenného života a je nevyhnutným predpokladom priaznivej prognózy pacienta. Kľúčové slová: bolesti brucha – žltačka – difúzny veľkobunkový B-lymfóm

Lack of association between peripheral activity of thyroid hormones and elevated TSH levels in childhood obesity

OBJECTIVE

An elevated thyroid stimulating hormone (TSH) level is a frequent finding in obese children, but its association with peripheral hormone metabolism is not fully understood. We hypothesized that in obesity, the changes in thyroid hormone metabolism in peripheral tissues might lead to dysregulation in the thyroid axis. The purpose of this study was to investigate the association of TSH with thyroid hormones in a group of obese children as compared to normal-weight controls.

METHODS

Serum TSH, free thyroxine (fT4) and free triiodothyronine (fT3) levels were measured in 101 obese children and in 40 controls. Serum reverse T3 (rT3) levels were also measured in a subgroup of 51 obese children and in 15 controls.

RESULTS

Serum TSH level was significantly higher in obese children compared to controls (2.78 vs. 1.99 mIU/L, p<0.001), while no difference was found in fT4, fT3, rT3 levels and in fT3/rT3 ratio. In the obese group, fT3 level positively correlated with fT4 (r=0.217, p=0.033) and inversely with rT3 (r=-0.288, p=0.045). However, thyroid hormone levels and TSH levels were not correlated.

CONCLUSION

In obese children, normal fT4, fT3 and rT3 levels suggest an undisturbed peripheral hormone metabolism. These levels show no correlation with elevated TSH levels.

[Genetics of monogenic forms of diabetes]

Monogenic diabetes mellitus is a type of diabetes, where genetics without any other factors is strong enough to cause the disease. According to the clinical features monogenic diabetes can be divided to the mild familial early onset diabetes, familial fasting hyperglycemia, diabetes with extrapancreatic features and neonatal diabetes mellitus. During the last several years the number of genes causing monogenic diabetes has continuously increased. The clinical picture of the monogenic diabetes is very heterogeneous, thus DNA analysis is required for identification of the diabetes etiology, which influences also the choice of treatment. This article is an overview of current knowledge on monogenic diabetes, focusing at the clinically and epidemiologically most important forms.