RefCurv: A software for the construction of pediatric reference curves

Reference data for body composition parameters in normal-weight Polish adolescents: results from the population-based ADOPOLNOR study

The aim of this study was to develop age- and sex-specific reference data for body composition parameters, including fat-free mass (FFM), body cell mass (BCM), fat mass (FM) and related indices, fat mass percentage (FM%), total body water (TBW) and muscle mass (MM) and to assess differences in these parameters between male and female adolescents. Bioelectrical impedance analysis (BIA) data were obtained from an ethnically homogeneous sub-sample of 4037 normal-weight participants selected on the basis of BMI from the total sample (2005 males and 2032 females aged 10-18 years) of the ADOPOLNOR study, a cross-sectional population-based survey conducted in western Poland. The LMS method and RefCurv version 0.4.2 software package were used to calculate centile values and plot smoothed centile curves. The results showed age-related changes in body composition parameters and a clear sexual dimorphism. From the age of 13 (for FFM) or 14 (for BCM, BCMI and MM) or throughout adolescence (for TBW and FFMI), boys had consistently higher values for these parameters than girls (p < 0.01 for each). However, they had significantly lower values for FM, FMI and FM% (1.3, 1.6 and 1.5 times lower at 18 years, respectively), indicating a lower proportion of body fat than girls (p < 0.01 for each). The centile values and curves were specific for boys and girls of all ages. Compared with other European adolescent cohorts, the data fit the normal-weight subsamples better than the population reference data.

CONCLUSION

This study provides reference data for body composition in normal (healthy) weight Polish adolescents, providing a contextualised framework that takes into account the unique physiological and environmental factors of the region. These reference data may also be useful for other Central European adolescents.

WHAT IS KNOWN

• Adolescence is a period of significant physical growth and increased susceptibility to nutritional problems due to factors such as suboptimal nutrition, unhealthy dietary choices, inadequate physical activity and psychosocial stressors related to body image concerns. • Body composition (BC) parameters, rather than BMI alone, are more effective in identifying nutritional abnormalities and health risks such as eating disorders, obesity and chronic diseases. Existing studies provide reference data for BC parameters, but often do not cover all relevant measures or specific regional populations.

WHAT IS NEW

• This study provides new age- and sex-specific reference values for a comprehensive range of body composition parameters, including body cell mass (BCM), total body water (TBW) and muscle mass (MM), in addition to fat-free mass (FFM) and fat mass (FM), in a large, ethnically homogeneous, normal-weight population of Polish adolescents aged 10-18 years. • These reference values for the normalweight cohort reflect healthy adolescent growth and body composition patterns, minimising bias from abnormal weight status. In addition, they can be applied to other Central European adolescent populations.

MULT: An allometric body mass index (ABMI) reference to assess nutritional status of multiethnic children and adolescents

OBJECTIVES

To develop an allometric body mass index (ABMI) reference that adjusts the weight in relation to height, taking into account the changes during development (MULT ABMI reference), and to compare it with international BMI references.

METHODS

The MULT ABMI reference was constructed through the LMS method, calculated with 65 644 ABMI observations of 17 447 subjects aged 5-22 years, from the United Kingdom, Ethiopia, India, Peru, Vietnam, Portugal, and Brazil. The M, S, and L curves of the MULT ABMI reference were compared with the curves of the MULT, World Health Organization (WHO), Centers for Disease Control and Prevention (CDC), International Obesity Task Force (IOTF), and Dutch Growth Study (DUTCH).

RESULTS

The greater differences in the M curve between MULT ABMI and WHO, CDC, IOTF, DUTCH, and MULT BMI references were around puberty (138 to 150 months for boys; 114 to 132 for girls). MULT ABMI presented S values similar to IOTF and DUTCH BMI references for boys 60 to 114 months and then became higher, approaching the MULT BMI S values from 198 to 240 months. For girls the MULT ABMI S values were close to the IOTF, CDC, and DUTCH from 60 to 110 months, and then became higher, approaching the MULT BMI S values until 240 months.

CONCLUSION

MULT ABMI presented an advantage in comparison to the existing BMI references because it takes into account the growth changes during puberty and is a new option to assess the nutritional status of multiethnic populations.

Cystinosis-associated metabolic bone disease across ages and CKD stages 1-5D/T

CONTEXT

The pathophysiology of cystinosis-associated metabolic bone disease is complex.

OBJECTIVE

We hypothesized a disturbed interaction between osteoblasts and osteoclasts.

DESIGN

Binational cross-sectional multicenter study.

SETTING

Hospital clinics.

PATIENTS

One hundred and three patients with cystinosis (61% children) with chronic kidney disease (CKD) stages 1-5D/T.

MAIN OUTCOME MEASURES

Ten key bone markers.

RESULTS

Skeletal complications occurred in two-thirds of the patients, with adults having a five-fold increased risk compared to children. Patients with CKD stages 1-3 showed reduced z-scores for serum phosphate and calcium, suppressed fibroblast growth factor 23 (FGF23) and parathyroid hormone levels in conjunction with elevated bone-specific alkaline phosphatase levels. Serum phosphate was associated with estimated glomerular filtration rate, combined phosphate and active vitamin D treatment, and native vitamin D supplementation, while serum calcium was associated with age and dosage of active vitamin D. Sclerostin was generally elevated in children, and associated with age, FGF23 levels, and treatment with active vitamin D and growth hormone. The osteoclast marker tartrate-resistant acid phosphatase 5b was increased, and associated with age and treatment with active vitamin D. The ratio of soluble ligand of receptor activator of nuclear factor-κB (sRANKL) and osteoprotegerin (OPG), a surrogate for the regulation of osteoclastogenesis by osteoblasts, was decreased and associated with phosphate and 1,25(OH)2D3 levels. These changes were only partly corrected after transplantation.

CONCLUSIONS

Bone health in cystinosis deteriorates with age, which is associated with increased osteoclast activity despite counterregulation of osteoblasts via OPG/RANKL, which in conjunction with elevated sclerostin levels and persistent rickets/osteomalacia may promote progressive bone loss.

Normative reference data for intracranial volume in children: The results of CT volumetry

BACKGROUND

Intracranial volume (ICV) is an important indicator of the development of the brain and skull in children. At present, there is a lack of ICV growth standards based on large infant and children samples. Our aim was to assess the normal range of the ICV variation in Russian children using a modern automatic system for constructing the endocranial cavity (Endex) and to provide growth standards of the ICV for clinical practice.

METHODS

High-resolution head CT scans were obtained from 673 apparently healthy children (380 boys and 293 girls) aged 0-17 years and transformed into the ICV estimates using the Endex software. The open-source software RefCurv utilizing R and the GAMLSS add-on package with the LMS method was then used for the construction of smooth centile growth references for ICV according to age and sex.

RESULTS

We demonstrated that the ICVs estimates calculated using the Endex software are perfectly comparable with those obtained by a conventional technique (i.e. seed feeling). Sex-specific pediatric growth charts for ICV were constructed.

CONCLUSIONS

This study makes available for use in clinical practice ICV growth charts for the age from 0 to 17 based on a sample of 673 high-resolution CT images.

Comparison of body mass index and fat mass index to classify body composition in adolescents-The EVA4YOU study

The objectives of this study were to develop age- and sex-specific reference percentiles for fat mass index (FMI) and fat-free mass index (FFMI) in adolescents aged 14 to 19 years and to determine differences in overweight/obesity classification by FMI and body mass index (BMI). The EVA4YOU study is a single-center cross-sectional study conducted in western Austria. Cardiovascular risks including anthropometric measurements and bioelectrical impedance analysis were assessed in adolescents (mean age 17 years). FMI and FFMI were calculated as the ratio of fat mass (FM) and fat-free mass (FFM) to the square of height and compared to study population-specific BMI percentiles. One thousand four hundred twenty-two adolescents were included in the analysis. Girls had a significantly higher mean FM and FMI and a significantly lower mean FFM, FFMI (p < 0.001, each), and mean BMI (p = 0.020) than boys. Body composition classification by FMI and BMI percentiles shows a concordance for the < 75th and > 97th percentile, but a significant difference in percentile rank classifications between these two cut-off values (all p < 0.05). Based on FMI, 15.5% (221/1422) of the whole population and 29.4% (92/313) of those between the 75th and 97th percentiles are classified one category higher or lower than those assigned by BMI.

CONCLUSION

 Classification of normal or pathologic body composition based on BMI and FMI shows good accordance in the clearly normal or pathologic range. In an intermediate range, FMI reclassifies categories based on BMI in more than a quarter of adolescents. Cut-off values to differentiate normal from pathologic FMI values on a biological basis are needed.

TRIAL REGISTRATION

The study is registered at www.

CLINICALTRIALS

gov  (Identifier: NCT04598685; Date of registration: October 22, 2020).

WHAT IS KNOWN

• Chronic non-communicable diseases (NCDs) are the leading cause of morbidity and mortality globally, with major risk factors including unhealthy diets, harmful behaviors, and obesity. Obesity in children and adolescents is a key risk factor for later NCDs, which is commonly measured by Body Mass Index (BMI). • BMI can be misleading as it doesn't distinguish between fat mass (FM) and fat-free mass (FFM), leading to potential misclassification of obesity in children. Previous studies have already suggested the use of the Fat Mass Index (FMI) and Fat-Free Mass Index (FFMI) as a more accurate measures of body composition.

WHAT IS NEW

• This study adds the first age- and sex-specific reference values for FMI and FFMI in Austrian adolescents using bioelectrical impedance analysis (BIA) as a safe and secure measurement method of a large representative cohort. • We found percentile misclassification between BMI and FMI when categorizing for obesity, especially in intermediate categories of body composition. Furthermore, when comparing the new reference values for FMI and FFMI to existing ones from the US, UK, and Germany we could show a good alignment within the European cohorts and major differences with American values, indicating and confirming the difference of FMI and FFMI for different populations of different ethnical background, living on different continents.

LMS-based continuous pediatric reference values for soluble receptor activator of nuclear factor kappa B ligand (sRANKL) and osteoprotegerin (OPG) in the HARP cohort

Soluble RANKL (sRANKL) and osteoprotegerin (OPG) are regulators of osteoclast differentiation and activation, but adequate pediatric reference values are lacking. Here we provide LMS (Lambda-Mu-Sigma)-based continuous pediatric reference percentiles for sRANKL, OPG and sRANKL/OPG ratio that will allow calculation of standardized patient z-scores to assess bone modeling in children.

PURPOSE

Soluble receptor activator of nuclear factor kappa B ligand (sRANKL) and osteoprotegerin (OPG) are regulators of osteoclast differentiation and activation and thus bone metabolic turnover in children. Adequate pediatric reference values for their serum/plasma concentrations are lacking. The development of Lambda-Mu-Sigma (LMS)-based continuous reference percentiles for laboratory parameters allow improved data interpretation in clinical practice.

METHODS

A total of 300 children aged 0.1-18 years (166 boys) were enrolled in the HAnnover Reference values for Pediatrics (HARP) study. sRANKL and OPG were assessed by ELISA. LMS-based continuous reference percentiles were generated using RefCurv software.

RESULTS

LMS-based percentiles were established for sRANKL, OPG and sRANKL/OPG ratio, which were all found to be age-dependent. sRANKL and sRANKL/OPG associated with sex. In boys, sRANKL percentiles were highest during infancy, followed by a continuous decline until the age of 7 years and a second peak around age 12-13 years. In girls, a continuous, slow decline of sRANKL percentiles was noticed from infancy onwards until the age of 13 years, followed by a rapid decline until adulthood. OPG percentiles continuously declined from infancy to adulthood. The percentiles for sRANKL/OPG ratio paralleled those of sRANKL. Serum concentrations of sRANKL correlated with OPG and serum phosphate z-scores, while OPG concentrations inversely associated with standardized body weight, BMI, and urinary phosphate to creatinine ratio (each p < 0.05).

CONCLUSION

This is the first report of LMS-based continuous pediatric reference percentiles for sRANKL, OPG and sRANKL/OPG ratio that allows calculation of standardized patient z-scores to assess bone metabolic turnover in children.

LMS-Based Pediatric Reference Values for Parameters of Phosphate Homeostasis in the HARP Cohort

CONTEXT

The assessment of phosphate homeostasis in children is challenging due to the marked changes in laboratory parameters during growth and development, and the lack of adequate reference values.

OBJECTIVE

To develop Lambda-Mu-Sigma (LMS)-based continuous pediatric reference percentiles for 7 key laboratory parameters of phosphate homeostasis.

METHODS

This cross-sectional, single-center study, the HAnnover Reference values for Pediatrics (HARP) study, included 455 children aged 0.1-18 years (254 boys) from outpatient hospital clinics and a secondary school program. Main outcome measures were LMS-based continuous reference percentiles for serum phosphate, plasma intact fibroblast growth factor 23 (iFGF23), and its cofactor soluble Klotho (sKlotho), tubular maximum phosphate reabsorption per glomerular filtration rate (TmP/GFR), fractional tubular reabsorption of phosphate (TRP), and urinary calcium/creatinine (Ca/Crea) and phosphate/creatinine (Pi/Crea) ratios.

RESULTS

LMS-based percentiles and z-scores were established for 7 key laboratory parameters of phosphate homeostasis, which were all found to be age-dependent. Serum phosphate, TmP/GFR, and sKlotho associated with sex. Serum phosphate, TmP/GFR, and urinary Ca/Crea and Pi/Crea levels were highest in infancy and declined until age 18 years, while phosphate and TmP/GFR values reached adult levels earlier in girls compared to boys. iFGF23 concentrations are highest in infancy and fall to a stable plateau by 4 years of age, while sKlotho peaks during adolescence.

CONCLUSION

This is the first report of LMS-based continuous pediatric reference percentiles for key laboratory parameters of phosphate homeostasis that allow calculation of standardized patient z-scores to facilitate test result interpretation in children and adolescents.

The development of a parent report instrument of early communication and language skills of infants and toddlers in mainland China

OBJECTIVE

This study was designed to produce a new parent-report measure, the Diagnostic Receptive Expressive Assessment of Mandarin-Infant Toddler Assessment of Communication and Language (DREAM-IT) in order to provide norms for the developmental skills of children aged 0-36 months in four areas: expressive language, receptive language, cognitive play and social skills.

METHODOLOGY

The scale was designed to be both broader and deeper than existing instruments that neglect one or more of these significant domains involved in early language. Items were chosen by a group of specialists with clinical experience working with the age group and with attention to the developmental literature. Caregivers were tested individually by a trained person who asked the questions and provided examples. In addition to an extensive health questionnaire, caregivers answered questions in Mandarin about their child's behaviour using a scale of 'not yet', 'sometimes' or 'always' or listing out words and/or sounds understood or said by the child. The 476 participating caregivers were recruited at maternal and child healthcare clinics centred in Chengdu, China, 191 of whom were tested a second time seven months later. The children were sampled in three-month age-bands from 0 to 36 months. The sample was balanced for child gender by age band, and parental education was balanced. Caregivers of 0-24-month-old children and caregivers of 12-36 months were each asked a different set of questions, to determine the appropriate age range and cutoff points for each question, requiring the sample size to be doubled for children aged 12-24 months.

RESULTS

The results were subject to item-response theory analysis to remove outlying items, and the resulting internal reliability was high for each domain (average Cronbach's alpha=0.87). The final instrument (between 67 and 113 questions in total) was refined to include the least redundant questions that had the highest intercorrelations, with attention paid to coverage of all domains across the age range. Two scales were developed: one for children 0-18 months, the second for children aged 18-36 months. The longitudinal design permitted the creation of growth curves and norms for each domain for six-month intervals from 0 to 36 months. A small sample of 32 parents of children with Down syndrome aged 18-36 months provided validation that the scales are highly sensitive to developmental delay.

CONCLUSION

The instrument shows considerable promise for detecting early communication problems in children in China.

WHAT THIS PAPER ADDS

What is already known on the subject In China, efforts were made in recent years to develop language assessments for infants and toddlers, but limitations existed with the domains included and number of items included per age group. Many clinical practitioners also continued to rely on language subtests of general developmental scales, which were limited in depth and breadth of language skills tested and were never intended for diagnosis of language delay. What this paper adds to existing knowledge This paper discusses the development of a valid caregiver report instrument for early communication and language skills of infants and toddlers in mainland China. The Diagnostic Receptive Expressive Assessment of Mandarin-Infant Toddler (DREAM-IT) includes foundational domains necessary for language and communication development in young children (receptive language, expressive language, cognitive play and social communication domains). The results show strong internal reliability (Cronbach's alpha) for each domain on a sample of 716 children sampled in three-month age bands from 0 to 36 months. The external validity proved strong when tested on a group of 32 young children with Down syndrome. What are the potential or actual clinical implications of this work? Besides helping to inform the diagnosis of language delays in infants and toddlers in China, the caregiver report instrument has special features to support clinical practitioners in a field that is just emerging in China. The unique support features include the automatic generation of a profile of relative strengths and weaknesses of the child on the report and the recommendation of child-specific caregiver coaching videos on a companion app.

MULT: A new BMI reference to assess nutritional status of multi-ethnic children and adolescents

OBJECTIVES

To develop a new Body Mass Index (BMI) reference (MULT) based on longitudinal data of multi-ethnic populations and to compare it to international BMI references.

METHODS

The MULT BMI reference was constructed through the LMS method and the Generalized Additive Models for Location Scale and Shape (GAMLSS), with 81 310 observations of 17 505 subjects aged 0-22 years old, from the United Kingdom, Ethiopia, Peru, India, Vietnam, Brazil, and Portugal. Outlier values were removed based on weight z-scores (population level) and based on BMI z-scores using the linear mixed effects model (individual level). The MULT M, S and L curves were compared to the ones of the World Health Organization (WHO), Centers for Disease Control and Prevention (CDC), International Obesity Task Force (IOTF), and Dutch Growth Study (DUTCH). The MULT BMI percentile cutoffs for overweight and obesity were calculated using the adult BMI values of 25 and 30 kg/m2 at 17, 18, 19, and 20 years old.

RESULTS

MULT presented the lowest mean BMI values for the ages 102-240 months for boys and 114-220 months for girls. MULT S values were similar to the WHO and IOTF for children under 60 months of age and the highest during puberty, while the L curve showed to be more symmetric than the other BMI references.

CONCLUSION

The MULT BMI reference was constructed based on recent data of populations from 10 countries, being a good option to assess the nutritional status of multi-ethnic populations.

Validation of attenuation imaging coefficient, shear wave elastography, and dispersion as emerging tools for non-invasive evaluation of liver tissue in children

Introduction

The number of children with acute and chronic liver disease is rising. Moreover, liver involvement may be limited to subtle changes in organ texture especially in early childhood and some syndromic conditions, such as ciliopathies. Attenuation imaging coefficient (ATI), shear wave elastography (SWE), and dispersion (SWD) are emerging ultrasound technologies providing data about attenuation, elasticity, and viscosity of liver tissue. This additional and qualitative information has been correlated with certain liver pathologies. However, limited data are available for healthy controls and have mainly been raised in adults.

Methods

This prospective monocentric study was conducted at a university hospital with a specialization in pediatric liver disease and transplantation. Between February and July 2021, 129 children aged 0-17.92 years were recruited. Study participants attended outpatient clinics due to minor illnesses excluding liver or cardiac diseases, acute (febrile) infections or other conditions affecting liver tissue and function. ATI, SWE, and SWD measurements were performed on an Aplio i800 (Canon Medical Systems) with an i8CX1 curved transducer by two different investigators with long-standing experience in pediatric ultrasound according to a standardized protocol.

Results

Considering multiple potential covariates, we derived percentile charts for all 3 devices relying on the Lambda-Mu-Sigma (LMS) approach. 112 children were considered for further analysis, excluding those with abnormal liver function and under-/overweight (BMI SDS<-1.96/> 1.96, respectively). Age range was 0-17.92 years (mean 6.89±0.50SD), 58% were male. The mean duration of the ultrasound examination (basic ultrasound plus SWE, SWD, and ATI) was 6.67±0.22 minutes and it was well tolerated in 83% (n=92) of cases. While ATI was related to age, SWD was found to depend on BMI SDS, and SWE on abdominal wall thickness and sex. ATI correlated with neither SWE nor SWD, but SWE was correlated with SWD.

Conclusions

Our study provides norm values and reference charts for ATI, SWE, and SWD considering important covariates including age, sex and, BMI. This may help to implement these promising tools into imaging diagnostics of liver disease and to improve the diagnostic relevance of liver ultrasound. In addition, these noninvasive techniques proved to be time-effective and highly reliable, which make them ideal for application in children.

Subclinical Hypothyroidism and Incident Depression in Adolescents and Young Adults: Results from a Nationwide Representative Prospective Study

Background: Although the relationship between subclinical hypothyroidism and major depressive disorder (MDD) has been studied in adults in cross-sectional and prospective population-based studies, this has not yet been done in adolescents. However, since thyroid function and MDD risk are subjected to maturational processes and ramifications of illness duration over the life span, these findings may not readily transfer to adolescents. Methods: The relationship between subclinical hypothyroidism and MDD was studied in a representative subsample of the nationwide KIGGS ("The German Health Interview and Examination Survey for Children and Adolescents") survey. A total of 4118 adolescents were examined over a median period of 6 years, and data were analyzed by a logistic regression approach accounting for important covariates related to thyroid function and/or MDD risk. The same approach was chosen to investigate the relationship between quartiles of thyrotropin (TSH) and free thyroxine (fT4) levels and incident MDD in euthyroid participants to broaden the focus on the relationship between thyroid hormone levels and MDD in a dose-response manner. Results: During the observation period, 121 cases of MDD were reported. There was no association between subclinical hypothyroidism and MDD when comparing 111 adolescents with subclinical hypothyroidism with 4007 euthyroid adolescents, representative of ∼106,000 and 3,610,000 adolescents from the general pediatric population, respectively. This also applied when studying the relationship between quartiles of TSH and fT4 levels and MDD in euthyroid participants. All results were confirmed by sensitivity analyses accounting for thyroid autoimmunity. Conclusions: Consistent with findings in adults, there is no association between subclinical hypothyroidism or quartiles of TSH and fT4 levels in the normal range and MDD in adolescents, despite potential age-related differences regarding thyroid function and MDD risk.

The adrenal steroid profile in adolescent depression: a valuable bio-readout?

There is preliminary evidence that adrenal steroids other than cortisol may be valuable biomarkers for major depressive disorder (MDD). So far, studies have been conducted in adults only, and conclusions are limited, mainly due to small sample sizes. Therefore, the present study assessed whether adrenal steroids serve as biomarkers for adolescent MDD. In 261 depressed adolescents (170 females) treated at a single psychiatric hospital, serum adrenal steroids (progesterone, 17-hydroxyprogesterone, 21-deoxycortisol, 11-deoxycortisol, cortisol, cortisone, deoxycorticosterone, corticosterone) were determined by liquid chromatography-tandem mass spectrometry. Findings were compared to that of an age- and sex-matched reference cohort (N = 255) by nonparametric analysis of variance. Nonparametric receiver operating characteristics (ROC) analyses were conducted to evaluate the diagnostic performance of single steroids and steroid ratios to classify depression status. Sensitivity analyses considered important confounders of adrenal functioning, and ROC results were verified by cross-validation. Compared to the reference cohort, levels of deoxycorticosterone and 21-deoxycortisol were decreased (P < 0.001). All other glucocorticoid- and mineralocorticoid-related steroids were increased (P < 0.001). The corticosterone to deoxycorticosterone ratio evidenced excellent classification characteristics, especially in females (AUC: 0.957; sensitivity: 0.902; specificity: 0.891). The adrenal steroid metabolome qualifies as a bio-readout reflecting adolescent MDD by a distinct steroid pattern that indicates dysfunction of the hypothalamus-pituitary-adrenal axis. Moreover, the corticosterone to deoxycorticosterone ratio may prospectively qualify to contribute to precision medicine in psychiatry by identifying those patients who might benefit from antiglucocorticoid treatment or those at risk for recurrence when adrenal dysfunction has not resolved.

Radioulnar interphalangeal joint angles in children and adolescents aged 0 to 19 years

The purpose of this study is to determine the normal ranges of radioulnar (i.e. medial-lateral) finger deviations during growth. We retrospectively measured radioulnar interphalangeal joint angles in 6236 properly aligned thumbs and fingers in trauma radiographs of 4720 patients aged 0 to 19 years. The mean interphalangeal joint angle of the thumb was 0.2° (standard deviation 1.5°). The average proximal interphalangeal joint angles were ulnar deviation of 2.5° (1.7°) for the index, ulnar deviation 1.7° (1.5°) for the middle, radial deviation 1.3° (1.8°) for the ring, radial deviation 2.0° (2.8°) for the little fingers. The distal interphalangeal joint angles were ulnar deviation of 2.5° (1.7°), ulnar deviation 2.1° (1.7°), radial deviation 2.1° (1.7°), radial deviation 5.1° (2.8°) from index to the little fingers. Thumbs were typically straight, whereas the index and middle fingers deviated ulnarly, and ring and little fingers radially. There were no relevant differences in sex or laterality.

Extremely and very preterm-born children <1500 g show different weight development in childhood compared to their peers

AIM

To develop reference growth charts for body mass index (BMI), weight, length and head circumference in children born extremely preterm (EPT) or very preterm (VPT) with a birth weight <1500 g.

METHODS

We analysed EPT and VPT children from the German Neonatal Network born between 2009 and 2013 without chronic diseases or medications influencing growth. These data of EPT and VPT datasets were split into a training dataset and a validation dataset. In the validation dataset, data from 385 EPT and 491 VPT children from birth to age 6 years were analysed to calculate growth charts.

RESULTS

The percentiles of length of EPT and VPT children were comparable to German reference percentiles. The BMI peak in infancy was attenuated, and BMI was lower in all the EPT and VPT children analysed. From 2 years until 6 years of age, head circumference was lower in EPT and VPT boys and girls.

CONCLUSION

Deficits in height described in EPT cohorts born during the 1980 s and 1990 s were not seen in our cohort. However, EPT and VPT born children showed growth patterns that differed from national reference curves for BMI. The growth charts provided here can be used to judge the growth of EPT and VPT born children.

Size Matters: The CAG Repeat Length of the Androgen Receptor Gene, Testosterone, and Male Adolescent Depression Severity

There is a distinct increase in the prevalence of depression with the onset of puberty. The role of peripubertal testosterone levels in boys in this context is insufficiently understood and may be modulated by a functional polymorphism of the androgen receptor gene (AR), a variable number of CAG repeats. Moreover, there is preliminary evidence that the relationship between testosterone, CAG repeat length, and the severity of depressive symptoms may differ between subclinical and overt depression, but this has neither been studied in a clinical sample of adolescents with depression nor compared between subclinical and overt depression in an adequately powered study. To investigate the relationship between free testosterone, CAG repeat length of the AR, depression status (subclinical vs. overt), and the severity of depressive symptoms, 118 boys treated as in- or daycare patients at a single psychiatric hospital were studied. Of these, 73 boys had at least mild depressive symptoms according to the Beck Depression Inventory-II (BDI-II > 13). Higher-order moderation analysis in the multiple regression framework revealed a constant relationship between free testosterone and depression severity irrespective of the number of CAG repeats in adolescents with a BDI-II score ≤ 13. In adolescents with a BDI-II score > 13, however, there was a significant negative relationship between free testosterone and BDI-II score in patients with <19 CAG repeats and a significant positive relationship regarding free testosterone and BDI-II score in those with more than 28 CAG repeats, even when considering important covariates. These results suggest that the effects of testosterone on mood in male adolescents with depression depend on the genetic make-up of the AR as well as on depression status. This complex relationship should be considered by future studies addressing mental health issues against an endocrine background and may, moreover, contribute to tailored treatment concepts in psychiatric medicine, especially in adults.