Early adiposity rebound and obesity in children with congenital hypothyroidism

Early adiposity rebound: predictors and outcomes

Adiposity rebound (AR) refers to the second rise of the body mass index (BMI) curve that usually occurs between six and eight years of age. AR timing has a significant impact on patients' health: early AR (EAR), usually before the age of five, is considered to be the earliest indicator of obesity and its related health conditions later in life. Many studies have evaluated factors that can be predictors of EAR, and identified low birth weight and gestational weight gain as novel predictors of EAR, highlighting the role of the intrauterine environment in the kinetics of adiposity. Furthermore, children with breastfeeding longer than 4 months have been found to be less likely to have an EAR, whereas children born to advanced-age mothers, high maternal BMI had a higher risk of having an EAR. Some differences were found in the timing of AR in boys and girls, with girls being more likely to have EAR. The aim of this review is to answer the following three questions: 1) Which are the prenatal and perinatal factors associated with increased risk of EAR? Is gender one of these? 2) Which are the outcomes of EAR in childhood and in adulthood? 3) Which measures can be taken in order to prevent premature AR?

Growth Pattern of Preterm Neonates with Fetal Growth Restriction: A Prospective Cohort Study

OBJECTIVES

To compare the growth of preterm neonates with fetal growth restriction (FGR) and preterm neonates born appropriate-for-gestational-age (AGA) from birth to 12-18 mo of corrected age (CA).

METHODS

In this prospective cohort study, 85 preterm neonates with FGR and 85 gestation- and gender-matched AGA neonates were followed up from birth till 12-18 mo corrected age. Anthropometric indices were compared at specific time points and the risk factors for underweight status were analyzed.

RESULTS

Mean gestational age of the cohort was 32.8 ± 2.1 wk. Mean birth weight was 1414 ± 248 g in the FGR and 1806 ± 416 g in AGA neonates. At 12-18 mo of corrected age, a significantly greater proportion of FGR infants were wasted (24.3% vs. 7.2%, P = 0.005). A greater proportion of FGR infants were underweight (27% vs. 17.4%, P = 0.11), stunted (41.9% vs. 36.2%, P = 0.30), and microcephalic (27% vs. 23.1%, P = 0.36), although the differences were not statistically significant. Significant catch-up growth from 40 wk postmenstrual age (PMA) to 12-18 mo corrected age in weight (52.8% vs. 13.1%, P <0.001) and length (37.9% vs. 8.7%, P <0.001) was observed in the FGR neonates. The z-score of weight for age at 3 mo (adjusted OR 0.65, 95% CI: 0.52-0.8; P <0.001), the median time to full feeds (aOR: 1.10, 95% CI: 1.04-1.15; P = 0.001), and hypothyroidism (aOR 2.44, 95% CI: 1.46-4.08; P = 0.001), were independent predictors of underweight status at 12-18 mo.

CONCLUSIONS

At 12-18 mo of corrected age, a significantly greater proportion of preterm FGR neonates were wasted compared to AGA ones. The former also exhibited significantly greater catch-up growth than the latter.

Guidelines for Newborn Screening of Congenital Hypothyroidism (2021 Revision)

Purpose of developing the guidelines: Newborn screening (NBS) for congenital hypothyroidism (CH) was started in 1979 in Japan, and early diagnosis and treatment improved the intelligence prognosis of CH patients. The incidence of CH was once about one in 5,000-8,000 births, but has been increased with diagnosis of subclinical CH. The disease requires continuous treatment and specialized medical facilities should conduct differential diagnosis and treatment in patients who are positive by NBS to avoid unnecessary treatment. The Guidelines for Mass Screening of Congenital Hypothyroidism (1998 version) were developed by the Mass Screening Committee of the Japanese Society for Pediatric Endocrinology in 1998. Subsequently, the guidelines were revised in 2014. Here, we have added minor revisions to the 2014 version to include the most recent findings. Target disease/conditions: Primary congenital hypothyroidism. Users of the Guidelines: Physician specialists in pediatric endocrinology, pediatric specialists, physicians referring pediatric practitioners, general physicians, laboratory technicians in charge of mass screening, and patients.

Causal Association Between Serum Thyrotropin and Obesity: A Bidirectional, Mendelian Randomization Study

CONTEXT

The association between serum thyrotropin (TSH) and obesity traits has been investigated previously in several epidemiological studies. However, the underlying causal association has not been established.

OBJECTIVE

This work aimed to determine and analyze the causal association between serum TSH level and obesity-related traits (body mass index [BMI] and obesity).

METHODS

The latest genome-wide association studies (GWASs) on TSH, BMI, and obesity were searched to obtain full statistics. Bidirectional 2-sample mendelian randomization (MR) was performed to explore the causal relationship between serum TSH and BMI and obesity. The inverse variance-weighted (IVW) and MR-Egger methods were used to combine the estimation for each single-nucleotide variation (formerly single-nucleotide polymorphism). Based on the preliminary MR results, free thyroxine (fT4) and free 3,5,3'-triiodothyronine (fT3) levels were also set as outcomes to further analyze the impact of BMI on them. BMI and obesity were treated as the outcomes to evaluate the effect of serum TSH on them, and TSH was set as the outcome to estimate the effect of BMI and obesity on it.

RESULTS

IVW and MR-Egger results both indicated that genetically driven serum TSH did not causally lead to changes in BMI or obesity. Moreover, the IVW method showed that the TSH level could be significantly elevated by genetically predicted high BMI (β = .038, SE = 0.013, P = .004). In further MR analysis, the IVW method indicated that BMI could causally increase the fT3 (β = 10.123, SE = 2.523, P < .001) while not significantly affecting the fT4 level.

CONCLUSION

Together with fT3, TSH can be significantly elevated by an increase in genetically driven BMI.

Clinical and endocrinological manifestations of childhood-onset craniopharyngioma before surgical removal: A report from one medical center in Taiwan

BACKGROUND

Craniopharyngiomas are benign tumors of embryologic origin located in the sellar region. Patients have both neurological and endocrinological symptoms. Symptoms may be subtle in the early clinical course, which leads to delayed diagnosis. This study evaluated the clinical and endocrinological manifestations of childhood-onset craniopharyngioma.

METHODS

We retrospectively reviewed medical records of 45 children diagnosed as having craniopharyngioma between 1995 and 2019. We collected data on clinical symptoms and signs, height, weight, biochemical and hormone data, images, operation records, and pathology reports. A three-graded classification system was applied to define the degree of hypothalamic damage (HD). We analyzed clinical and endocrinological manifestations among patients with and without obesity, with short and normal stature, and with differing degrees of HD.

RESULTS

Clinical endocrinologic manifestations included adrenocortical insufficiency (42%), central hypothyroidism (37%), short stature (31%), obesity (20%), weight < third percentile (19%), and polyuria or polydipsia (11%). The distribution of height and body mass index (BMI) revealed that a relatively large proportion of patients had short stature and obesity compared to the general population. Patients with grade 2 HD were significantly taller (height median SDS -0.07 vs. -2.05, P = 0.032), and had higher BMI (BMI median standard deviation scores [SDS] 1.14 vs. -0.54, P = 0.039) and shorter time to diagnosis (0.27 vs. 8.29 months, P = 0.007) than were those in the grade 0-1 HD. Delayed diagnosis was associated with short stature (6/7 vs. 4/26, P = 0.001) and no initial neurological symptoms (4/7 vs. 2/28, P = 0.009).

CONCLUSION

Growth patterns may change variously depend on the tumor location and the severity of hypothalamic damage. Therefore, monitoring possible neurological symptoms and evaluating the growth patterns of patients during regular outpatient clinical visits are paramount.

Congenital Hypothyroidism: A 2020-2021 Consensus Guidelines Update-An ENDO-European Reference Network Initiative Endorsed by the European Society for Pediatric Endocrinology and the European Society for Endocrinology

Background: An ENDO-European Reference Network (ERN) initiative was launched that was endorsed by the European Society for Pediatric Endocrinology and the European Society for Endocrinology with 22 participants from the ENDO-ERN and the two societies. The aim was to update the practice guidelines for the diagnosis and management of congenital hypothyroidism (CH). A systematic literature search was conducted to identify key articles on neonatal screening, diagnosis, and management of primary and central CH. The evidence-based guidelines were graded with the Grading of Recommendations, Assessment, Development and Evaluation system, describing both the strength of recommendations and the quality of evidence. In the absence of sufficient evidence, conclusions were based on expert opinion. Summary: The recommendations include the various neonatal screening approaches for CH as well as the etiology (also genetics), diagnostics, treatment, and prognosis of both primary and central CH. When CH is diagnosed, the expert panel recommends the immediate start of correctly dosed levothyroxine treatment and frequent follow-up including laboratory testing to keep thyroid hormone levels in their target ranges, timely assessment of the need to continue treatment, attention for neurodevelopment and neurosensory functions, and, if necessary, consulting other health professionals, and education of the child and family about CH. Harmonization of diagnostics, treatment, and follow-up will optimize patient outcomes. Lastly, all individuals with CH are entitled to a well-planned transition of care from pediatrics to adult medicine. Conclusions: This consensus guidelines update should be used to further optimize detection, diagnosis, treatment, and follow-up of children with all forms of CH in the light of the most recent evidence. It should be helpful in convincing health authorities of the benefits of neonatal screening for CH. Further epidemiological and experimental studies are needed to understand the increased incidence of this condition.

Pubertal development and adult height in patients with congenital hypothyroidism detected by neonatal screening in southern Brazil

Objectives Adequate treatment of congenital hypothyroidism (CH) is required for normal growth and sexual development. To evaluate pubertal development in patients with permanent CH detected by a statewide Neonatal Screening Program of Paraná and, secondly, to evaluate adult height (AH) in a subgroup of patients. Methods Clinical, laboratory, and auxological data obtained from medical records of 174 patients (123 girls). Results Median chronological age (CA) at treatment initiation was 24 days, and mean initial levothyroxine dose was 11.7 ± 1.9 μg/kg/day; mean CA at puberty onset was 11.5 ± 1.3 years (boys) and 9.7 ± 1.2 years (girls); mean CA in girls who underwent menarche (n=81) was 12.1 ± 1.1 years. Thyroid-stimulating hormone (TSH) values above the normal range were observed in 36.4% of the boys and 32.7% of the girls on puberty onset, and in 44.6% around menarche. Among 15 boys and 66 girls who had reached the AH, the median height z-score value was significantly greater than the target height (TH) z-score value in boys (p=0.01) and in girls (p<0.001). Boys with normal TSH values at puberty onset had greater mean AH z-score compared with boys with TSH values above the normal range (p=0.04). Conclusions In this group, pubertal development in girls with CH was not different from that reported in healthy girls in the general Brazilian population. Boys with higher TSH at puberty onset may have an increased risk of not reaching their potential height compared with those with normal TSH during this period. In a subgroup who attained AH, the median AH z-score was greater than the median TH z-score.

Thyroid Deficiency Before Birth Alters the Adipose Transcriptome to Promote Overgrowth of White Adipose Tissue and Impair Thermogenic Capacity

Background: Development of adipose tissue before birth is essential for energy storage and thermoregulation in the neonate and for cardiometabolic health in later life. Thyroid hormones are important regulators of growth and maturation in fetal tissues. Offspring hypothyroid in utero are poorly adapted to regulate body temperature at birth and are at risk of becoming obese and insulin resistant in childhood. The mechanisms by which thyroid hormones regulate the growth and development of adipose tissue in the fetus, however, are unclear. Methods: This study examined the structure, transcriptome, and protein expression of perirenal adipose tissue (PAT) in a fetal sheep model of thyroid hormone deficiency during late gestation. Proportions of unilocular (UL) (white) and multilocular (ML) (brown) adipocytes, and UL adipocyte size, were assessed by histological and stereological techniques. Changes to the adipose transcriptome were investigated by RNA sequencing and bioinformatic analysis, and proteins of interest were quantified by Western blotting. Results: Hypothyroidism in utero resulted in elevated plasma insulin and leptin concentrations and overgrowth of PAT in the fetus, specifically due to hyperplasia and hypertrophy of UL adipocytes with no change in ML adipocyte mass. RNA sequencing and genomic analyses showed that thyroid deficiency affected 34% of the genes identified in fetal adipose tissue. Enriched Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) pathways were associated with adipogenic, metabolic, and thermoregulatory processes, insulin resistance, and a range of endocrine and adipocytokine signaling pathways. Adipose protein levels of signaling molecules, including phosphorylated S6-kinase (pS6K), glucose transporter isoform 4 (GLUT4), and peroxisome proliferator-activated receptor γ (PPARγ), were increased by fetal hypothyroidism. Fetal thyroid deficiency decreased uncoupling protein 1 (UCP1) protein and mRNA content, and UCP1 thermogenic capacity without any change in ML adipocyte mass. Conclusions: Growth and development of adipose tissue before birth is sensitive to thyroid hormone status in utero. Changes to the adipose transcriptome and phenotype observed in the hypothyroid fetus may have consequences for neonatal survival and the risk of obesity and metabolic dysfunction in later life.

Confirmatory factor analysis of the parental feeding style questionnaire with a preschool sample

PURPOSE

Despite being widely used, there has not yet been a confirmatory factor analysis (CFA) on the English version of the Parental Feeding Style Questionnaire (PFSQ). Preschool is a critical time to assess parental feeding styles, and the PFSQ is one of the few measures that can be used with young children. As such, the current study conducted the first CFA on the PFSQ in an English-speaking sample in the United States to establish preliminary evidence of its factor structure.

METHODS

Parents of preschoolers aged 3-5 years (N = 297; M = 33.47 years; 85.2% mothers) presenting to a pediatric dentistry office in the Midwest of the United States were recruited to participate in this cross-sectional study. Parents completed the PFSQ in the waiting room of the dental office. Robust maximum likelihood factor analyses were conducted on the PFSQ.

RESULTS

The original four-factor model was not confirmed, but rather, results provided preliminary support for a five-factor solution: Control over Eating, Instrumental Feeding, Emotional Feeding, Encouragement of Variety, and Prompting of Eating, CFI = 0.91, SRMR = 0.06, RMSEA = 0.05.

CONCLUSIONS

The PFSQ is a widely used measure for assessing parental feeding styles in young children. However, the CFA indicated that the originally proposed four-factor structure did not fit well. Certain modifications to the measure were necessary to improve model fit. A five-factor model fit better, and six items were removed, reducing the original 27-item scale to 21 items.

LEVEL OF EVIDENCE

Level V, cross-sectional descriptive study.

The relationship between nonalcoholic fatty liver disease and pediatric congenital hypothyroidism patients

Previous studies have shown hypothyroidism was independently associated with nonalcoholic fatty liver disease (NAFLD) in adults, but few studies examined their relationships in pediatric populations. This study aimed to investigate the prevalence of NAFLD in pediatric congenital hypothyroidism (CHT) patients and to identify the association between CHT and NAFLD. This study enrolled pediatric CHT patients receiving levothyroxine treatment at one medical center from 2013 to 2014. Euthyroid subjects (ET) and transient hypothyroidism (THT) patients weaned off medication successfully after age 3 were selected for further comparison. Laboratory data including thyroid functions, liver functions, and metabolic profiles were obtained. The major outcome was the occurrence of NAFLD, diagnosed based on the findings of abdominal ultrasonography. One-hundred and twenty-nine subjects (47 in CHT, 47 in THT, and 35 in ET groups) were enrolled. The analysis showed higher fasting serum glucose, insulin, thyroxine (T4), and mean thyroid-stimulating hormone (TSH) levels in the CHT group. NAFLD prevalence was higher in the CHT (23.4%) group than in the THT (8.5%) and the ET (5.7%) groups, demonstrating an increasing trend across three strata (X² _{linear-by-linear} = 5.9, P < .05). The multivariate regression analysis showed obesity (β-coefficient = 5.52, P < .05), CHT (β-coefficient = 2.92, P < .05) and mean TSH levels (β-coefficient = 0.24, P < .05) were independent risk factors for NAFLD. A positive correlation was found between TSH level and lipid profiles. CHT patients had higher risk of NAFLD despite treatment being initiated early in life. Close monitoring of metabolic profiles is warranted. Further research should examine ways to optimize the treatment for CHT patients in terms of prevention against NAFLD.

Early adiposity rebound in patients with Prader-Willi syndrome

Background Prader-Willi syndrome (PWS) is associated with marked obesity that can lead to severe complications such as diabetes mellitus. Early adiposity rebound (AR) is associated with future obesity and an increased risk of diabetes mellitus and metabolic syndrome. Previous reports have shown that the onset of AR occurred earlier in diseases that cause obesity. However, there have been no studies focusing on the timing of AR in PWS, or on the effect of growth hormone (GH) treatment on AR. The aim of this study was to explore AR in PWS patients and to analyze the effect of GH treatment on AR. Methods This retrospective study evaluated 48 patients, with 16 of the patients found to have AR prior to GH treatment. AR was constructed for each patient using Microsoft Excel, and the exact point of the nadir of body mass index (BMI) following the initial peak was determined. We additionally analyzed the relationship between GH treatment and the timing of AR onset. Results AR onset for patients found to have AR before starting GH treatment was 16.0 (13.0-21.0) months. In contrast, AR onset for patients found to have AR after starting GH treatment was 27.5 (23.8-36.3) months. The difference between the two groups was statistically significant (p=0.0001). A positive correlation was found between the GH treatment period and AR (p=0.00013). Conclusion The median age of AR onset in PWS patients was 16.0 (13.0-21.0) months, and GH treatment might delay the early AR onset.