The LIFE child study: a life course approach to disease and health

Omentin-1 and NAMPT serum concentrations are higher and CK-18 levels are lower in children and adolescents with type 1 diabetes when compared to healthy age, sex and BMI matched controls

Background Adipokines were shown to affect glucose homeostasis and β-cell function in patients with pancreatic dysfunction which is associated with changes in the adipose tissue secretory profile. However, information about adipokines associated with β-cell dysfunction is lacking in pediatric patients with type 1 diabetes. Methods (1) We compared serum concentrations of nicotinamide phosphoribosyltransferase (NAMPT), omentin-1 and caspase-cleaved cytokeratin 18 fragment M30 (CK-18) in pediatric type 1 diabetes patients (n=245) and healthy age, sex and body mass index standard deviation score (BMI-SDS) matched controls (n=243). (2) We investigated the influence of insulin treatment on serum concentrations of NAMPT, omentin-1 and CK-18 in groups of patients with type 1 diabetes stratified according to the duration of their disease: at onset (n=50), ≥6 months and <5 years (n=185), ≥5 and <10 years (n=98), and ≥10 years (n=52). Results Patients at onset compared with healthy controls demonstrated no significant differences in NAMPT levels (p=0.129), whereas omentin-1 levels were elevated (p<0.001) and CK-18 levels were lowered (p=0.034). In contrast, NAMPT and omentin-1 were elevated and CK-18 serum levels were lower in longstanding patients compared to healthy controls (p<0.001). NAMPT serum levels did not change significantly during the duration of type 1 diabetes (p=0.546). At onset, omentin-1 and CK-18 levels were higher than in any group of longstanding type 1 diabetes (p<0.025). Conclusions Altered serum levels of NAMPT, omentin-1 and CK-18 in pediatric type 1 diabetes patients indicate metabolic changes caused by adipose tissue dysregulation which do not normalize during insulin therapy.

Longitudinal anthropometry of children and adolescents using 3D-body scanning

3D-body scanning anthropometry is a suitable method for characterization of physiological development of children and adolescents, and for understanding onset and progression of disorders like overweight and obesity. Here we present a novel body typing approach to describe and to interpret longitudinal 3D-body scanning data of more than 800 children and adolescents measured in up to four follow-ups in intervals of 1 year, referring to an age range between 6 and 18 years. We analyzed transitions between body types assigned to lower-, normal- and overweight participants upon development of children and adolescents. We found a virtually parallel development of the body types with only a few transitions between them. Body types of children and adolescents tend to conserve their weight category. 3D body scanning anthropometry in combination with body typing constitutes a novel option to investigate onset and progression of obesity in children.

Stress-related hormones in association with periodontal condition in adolescents-results of the epidemiologic LIFE Child study

OBJECTIVES

The aim of this study was to investigate the associations between blood levels of stress-related hormones and early signs of periodontal disease in children and adolescents.

MATERIALS AND METHODS

Within the LIFE (Leipzig research center for civilization diseases) Child study, 498 adolescents (10 to 18 years) were included. Early signs of periodontal inflammation were measured by probing depth (PD) at six index teeth (16, 11, 26, 36, 31, 46). Blood levels of stress-related hormones (cortisol, dehydroepiandosterone-sulfate [DHEA-S]) and, additionally interleukine-6 (IL-6) were measured. Socioeconomic status, oral hygiene, orthodontic appliances, and nutritional status, recorded by body-mass-index-standard-deviation-score (BMI-SDS), were considered as confounding factors. Additionally, in 98 participants, an oral chairside active matrix metalloproteinase-8 (aMMP-8) test was performed. Statistical tests are the Mann-Whitney U tests, chi-squared tests and multivariate logistic regression model.

RESULTS

IL-6, BMI-SDS as well as positive aMMP-8 test result were significantly associated with maximum PD > 3 mm (p < 0.05). However, no statistically significant associations between stress-related hormones (cortisol and DHEA-S) and presence of maximum PD > 3 mm were found (p > 0.05). Higher DHEA-S and BMI were associated with positive aMMP-8 result, even after adjusting for age and gender (p = 0.027, p_adj = 0.026).

CONCLUSION

The results reveal no associations between PD and stress-related hormones cortisol and DHEA-S. aMMP-8 test result might be associated with DHEA-S level. Nutritional status seems to influence periodontal disease in adolescents.

CLINICAL RELEVANCE

DHEA-S and BMI-SDS show associations with early signs of periodontal disease in adolescents aged 10 to 18 years. This association should be confirmed by the investigation of high-risk groups.

Speaking Voice in Children and Adolescents: Normative Data and Associations with BMI, Tanner Stage, and Singing Activity

OBJECTIVES

The aim of this study was to establish normative data concerning the speaking voice of children and adolescents for clinical diagnostics.

STUDY DESIGN

Population-based mixed cross-sectional and longitudinal childhood cohort study.

METHODS

Normative data measuring the speaking voice profile of 1352 male and 1274 female participants aged 6 to 17 years were collected. To evaluate the voice range, five different intensity levels as the quietest voicing speaking voice (Level I), conversational voice (Level II), classroom voice (Level III), shouting voice (Level IV), and again the quietest speaking voice (Level V) were investigated. Multivariable analyses were performed to describe the effects of body mass index, Tanner stage, and singing activity on the outcome variables.

RESULTS

A clear distinction in frequencies and sound pressure levels between the five different voice levels can be found in both genders. In females the mean fundamental frequency of the conversational voice lowers from 223.3 to 205.8 Hz. In male participants it lowers from 223.3 to 102.3 Hz. The most substantial decrease in the fundamental frequency of the speaking voice in boys occurs at 13.5 years. Girls show an almost continuous decline in their fundamental frequency. Only the Tanner stage showed significant positive relationships with the grade of lowering of the fundamental frequency in both sexes.

CONCLUSIONS

It was shown that the investigation of the speaking voice using predefined intensity-levels represents a feasible examination for children and adolescents. This study provides reference data on the range and age-adjusted normative values of the speaking voice.

Cross-sectional and longitudinal associations of screen time and physical activity with school performance at different types of secondary school

Background

Previous studies have already reported associations of media consumption and/or physical activity with school achievement. However, longitudinal studies investigating independent effects of physical activity and media consumption on school performance are sparse. The present study fills this research gap and, furthermore, assesses relationships of the type of secondary school with media consumption and physical activity.

Methods

The consumption of screen-based media (TV/video, game console, PC/internet, and mobile phone) and leisure physical activity (organized and non-organized) of 10 – to 17-year old adolescents participating in the LIFE Child study in Germany were related to their school grades in two major school subjects (Mathematics and German) and in Physical Education. In addition to a cross-sectional analysis at baseline (N = 850), a longitudinal analysis (N = 512) investigated the independent effects of these activities on the school grades achieved 12 months later. All associations were adjusted for age, gender, socio-economic status, year of data assessment, body-mass-index, and school grades at baseline. A further analysis investigated differences in the consumption of screen-based media and physical activity as a function of the type of secondary school (highest vs. lower secondary school).

Results

Adolescents of lower secondary schools reported a significantly higher consumption of TV/video and game consoles than adolescents attending the highest secondary school. Independently of the type of school, a better school performance in Mathematics was predicted by a lower consumption of computers/internet, and a better performance in Physical Education was predicted by a lower consumption of TV/video and a higher frequency of non-organized physical activity. However, the association between non-organized physical activity and subsequent grades in Physical Education was significant in girls only.

Conclusion

The present results suggest that media consumption has a negative effect on school achievement, whereas physical activity has a positive effect, which, however, is restricted to the subject Physical Education. Future studies might explore the relationship between media consumption and school career, for example, the choice or change of the secondary school type, in more detail.

Trial registration

LIFE Child study: ClinicalTrials.gov, clinical trial number NCT02550236

Reciprocal Associations between Electronic Media Use and Behavioral Difficulties in Preschoolers

The use of electronic media has increased substantially and is already observable in young children. The present study explored associations of preschoolers’ use of electronic media with age, gender, and socio-economic status, investigated time trends, and examined reciprocal longitudinal relations between children’s use of electronic media and their behavioral difficulties. The study participants included 527 German two- to six-year-old children whose parents had provided information on their use of electronic media and their behavioral difficulties at two time points, with approximately 12 months between baseline and follow-up. The analyses revealed that older vs. younger children, as well as children from families with a lower vs. higher socio-economic status, were more often reported to use electronic media. Furthermore, the usage of mobile phones increased significantly between 2011 and 2016. Most interestingly, baseline usage of computer/Internet predicted more emotional and conduct problems at follow-up, and baseline usage of mobile phones was associated with more conduct problems and hyperactivity or inattention at follow-up. Peer relationship problems at baseline, on the other hand, increased the likelihood of using computer/Internet and mobile phones at follow-up. The findings indicate that preschoolers’ use of electronic media, especially newer media such as computer/Internet and mobile phones, and their behavioral difficulties are mutually related over time.

Factors associated with the emotional health of children: high family income as a protective factor

Anxiety and depressive symptoms have adverse effects on children's development. The present study investigates the associations of socioeconomic factors as well as maternal emotional health with children's emotional health status. The data were collected between 2011 and 2015 in the LIFE Child study, a population-based cohort study in Leipzig, Germany. The emotional health status of 1093 children (2.5-11.9 years old) was investigated using the subscale 'emotional problems' of the Strengths and Difficulties Questionnaire. Associations of maternal emotional health, family status, and socioeconomic status (SES) with the emotional health status of children were estimated via regression analyses. 21.13% of the participating children were assigned to the 'risk' group for emotional problems. The results furthermore revealed that children of mothers reporting more depressive symptoms, children living in single-parent families, and children of families with lower SES scored higher in the emotional problems scale. When considering the different indicators of SES (parental education, occupational status, and monthly net income) separately, only income showed significant associations with children's emotional health status. The prevalence of emotional problems in children in Leipzig, a city in East Germany, appears to be higher than the previously reported German average. Maternal depressive symptoms, single-parent families, lower SES, and especially lower income can be seen as risk factors for children's emotional health.

Does physiological distribution of blood parameters in children depend on socioeconomic status? Results of a German cross-sectional study

OBJECTIVES

In the present study, we examined the relation between socioeconomic status (SES) and the physiological distribution of iron-related blood parameters.

DESIGN

This is a cross-sectional analysis of longitudinal population-based cohort study.

SETTING

Based on a sample of healthy participants from a German research centre, various blood parameters and values of clinical examinations and questionnaires were collected.

PARTICIPANTS

A total of 1206 healthy volunteers aged 2.5 to 19 years, one child per family randomly selected, were included.

PRIMARY AND SECONDARY OUTCOME MEASURES

Associations between the SES of children by Winkler-Stolzenberg Index (WSI) and its dimensions (income, education, occupation) and iron-related blood parameters (haemoglobin, ferritin and transferrin) were analysed by linear regression analyses. Gender and pubertal stage were included as covariables. Additionally, associations between SES of children by WSI and physical activity (side-to-side jumps, push-ups) as well as body mass index (BMI) were analysed by linear regression analyses.

RESULTS

Children with high WSI or family income showed significantly increased z-scores for haemoglobin (P=0.046; P<0.001). Children with increased WSI or family income showed significantly lower z-scores for transferrin (P<0.001). There was a significant correlation between haemoglobin and gender (P<0.001) and between transferrin and pubertal stage (P=0.024). Furthermore, physical activity was positively correlated and BMI was negatively correlated with WSI (P<0.001).

DISCUSSION

Our data show an association between SES and the distribution of iron-dependent parameters. Lower SES is correlated with lower values for haemoglobin and higher values for transferrin. Furthermore, we demonstrate that physical activity and BMI are associated with SES. Whereas higher SES is correlated with higher values for physical activity and lower BMI. Our parameters are standardised as z-scores with the advantages that the results are comparable across different age groups and present physiological courses.

TRIAL REGISTRATION NUMBER

NCT02550236; Results.

Evaluation of hair cortisol and cortisone change during pregnancy and the association with self-reported depression, somatization, and stress symptoms

Hair cortisol levels are used to measure long-term stress, while its inactive metabolite cortisone is often not assessed. We measured hair cortisol concentrations (HCC) and hair cortisone concentrations (HCNC) via liquid chromatography quadrupole linear ion trap mass spectrometry (LC-MS³) in 62 pregnant women who participated in the LIFE CHILD STUDY in their 2nd and 3rd trimester between 12/2011 and 11/2014. Sociodemographic factors, pregnancy-related factors, and hair characteristics were assessed. Degree of severity of depression, somatization, and stress were evaluated in both trimesters with a self-reported Patient Health Questionnaire (PHQ). Multivariate regression analyses were conducted between HCC and potential influencing factors, as well as with subscales of the PHQ, with HCNC and with the ratio of HCNC to HCC. Spearman correlation coefficients were calculated between steroid concentrations and subscale scores of the PHQ, as well as between the log₂-fold change in HCC and HCNC and the change in PHQ subscale scores. HCC increased 1.3-fold and HCNC increased 1.5-fold by the 3rd trimester. HCNC was more than three times higher than HCC in both trimesters. We found significant associations of PHQ subscores with HCNC. The PHQ depression score was negatively correlated with HCNC in the 2nd trimester (p < .05). The PHQ stress score change was negatively correlated with the fold change of HCNC (p < .05) and with the change in the ratio of HCNC to HCC (p < .001). Our study suggests an association of cortisol/cortisone metabolism with self-reported stress in the 2nd and 3rd trimester of pregnancy. Since associations with PHQ subscores were only found with cortisone or the ratio of cortisone to cortisol, but not with cortisol alone, both cortisone and cortisol should be used as a marker for stress in pregnant woman.

Body typing of children and adolescents using 3D-body scanning

Three-dimensional (3D-) body scanning of children and adolescents allows the detailed study of physiological development in terms of anthropometrical alterations which potentially provide early onset markers for obesity. Here, we present a systematic analysis of body scanning data of 2,700 urban children and adolescents in the age range between 5 and 18 years with the special aim to stratify the participants into distinct body shape types and to describe their change upon development. In a first step, we extracted a set of eight representative meta-measures from the data. Each of them collects a related group of anthropometrical features and changes specifically upon aging. In a second step we defined seven body types by clustering the meta-measures of all participants. These body types describe the body shapes in terms of three weight (lower, normal and overweight) and three age (young, medium and older) categories. For younger children (age of 5-10 years) we found a common 'early childhood body shape' which splits into three weight-dependent types for older children, with one or two years delay for boys. Our study shows that the concept of body types provides a reliable option for the anthropometric characterization of developing and aging populations.

Endocrinological and subjective stress responses in children with depressive, anxiety, or externalizing disorders

In this study, we used a stress test to investigate endocrinological and subjective stress responses of 8- to 14-year-old children with internalizing or externalizing disorders and healthy controls. The sample (N = 170) consisted of clinical and community children. Parents were given a diagnostic interview to diagnose their children's psychiatric condition. We measured saliva cortisol and subjectively experienced arousal in children before and after the Trier Social Stress Test for Children. Children also rated their performance immediately after the stress test, and 1 hr later they rated their positive and negative thoughts about this stressful event. Children with internalizing or externalizing disorders exhibited a blunted cortisol response compared to healthy controls. Depressed children rated their test performance lower and reported more negative thoughts after the test in comparison to healthy controls, anxious children reported more arousal before and after the task, and children with externalizing disorders reported more positive thoughts. In regression analyses, cortisol and subjective stress responses were both predictive of psychiatric disorders. The study extends previous work on the relation between psychiatric disorders and children's stress responses to an experimentally induced stress task by including a broad range of psychiatric disorders and by integrating endocrinological and subjective stress responses.

Rare Variant Analysis of Human and Rodent Obesity Genes in Individuals with Severe Childhood Obesity

Obesity is a genetically heterogeneous disorder. Using targeted and whole-exome sequencing, we studied 32 human and 87 rodent obesity genes in 2,548 severely obese children and 1,117 controls. We identified 52 variants contributing to obesity in 2% of cases including multiple novel variants in GNAS, which were sometimes found with accelerated growth rather than short stature as described previously. Nominally significant associations were found for rare functional variants in BBS1, BBS9, GNAS, MKKS, CLOCK and ANGPTL6. The p.S284X variant in ANGPTL6 drives the association signal (rs201622589, MAF~0.1%, odds ratio = 10.13, p-value = 0.042) and results in complete loss of secretion in cells. Further analysis including additional case-control studies and population controls (N = 260,642) did not support association of this variant with obesity (odds ratio = 2.34, p-value = 2.59 × 10-3), highlighting the challenges of testing rare variant associations and the need for very large sample sizes. Further validation in cohorts with severe obesity and engineering the variants in model organisms will be needed to explore whether human variants in ANGPTL6 and other genes that lead to obesity when deleted in mice, do contribute to obesity. Such studies may yield druggable targets for weight loss therapies.

aMMP-8 in correlation to caries and periodontal condition in adolescents-results of the epidemiologic LIFE child study

OBJECTIVES

The suitability of a chairside aMMP-8 test in determination of periodontal inflammation and caries in adolescents was assessed. Secondly, the influence of orthodontic treatment on aMMP-8 test result was analyzed.

MATERIALS AND METHODS

Within the LIFE Child study, 434 adolescents (10 to 18 years) were included. Clinical dental examinations comprised caries experience (DMF/T-Index), signs of periodontal inflammation (probing pocket depth, PPD; community periodontal index of treatment needs; CPITN) at six index teeth and oral hygiene (OH). Information about orthodontic appliances (OA) and socioeconomic status (SES) were obtained by validated questionnaires. Test's sensitivity and specificity to detect periodontal inflammation and carious lesions were evaluated. The influence of OA on the test result was analyzed (multivariate model).

RESULTS

No associations between age, gender, SES or OH, and test outcome were found (p > 0.05). Positive test results correlated to periodontal findings (CPITN, mean PPD; p < 0.001). However, for the detection of ≥ 1 site(s) with PPD ≥ 4 mm, the test's sensitivity and specificity were found to be 61 and 69%, respectively. Multivariate analysis revealed a higher probability for a positive test result in cases of fixed OA (odds ratio 5.02, 95% confidence interval 1.90-13.19). The test had no diagnostic value considering carious lesions.

CONCLUSIONS

The chairside aMMP-8 test does not reliably identify adolescents with periodontal inflammation. Positive test results were more frequent in case of OA.

CLINICAL RELEVANCE

The chairside aMMP-8 test is no appropriate tool to screen children and adolescents neither for periodontal inflammation nor for carious lesions.

An 8-item short form of the Eating Disorder Examination-Questionnaire adapted for children (ChEDE-Q8)

Eating disturbances are common in children placing a vulnerable group of them at risk for full-syndrome eating disorders and adverse health outcomes. To provide a valid self-report assessment of eating disorder psychopathology in children, a short form of the child version of the Eating Disorder Examination (ChEDE-Q) was psychometrically evaluated. Similar to the EDE-Q, the ChEDE-Q provides assessment of eating disorder psychopathology related to anorexia nervosa, bulimia nervosa, and binge-eating disorder; however, the ChEDE-Q does not assess symptoms of avoidant/restrictive food intake disorder, pica, or rumination disorder. In 1,836 participants ages 7 to 18 years, recruited from two independent population-based samples, the factor structure of the recently established 8-item short form EDE-Q8 for adults was examined, including measurement invariance analyses on age, gender, and weight status derived from objectively measured weight and height. For convergent validity, the ChEDE-Q global score, body esteem scale, strengths and difficulties questionnaire, and sociodemographic characteristics were used. Item characteristics and age- and gender-specific norms were calculated. Confirmatory factor analysis revealed good model fit for the 8-item ChEDE-Q. Measurement invariance analyses indicated strict invariance for all analyzed subgroups. Convergent validity was provided through associations with well-established questionnaires and age, gender, and weight status, in expected directions. The newly developed ChEDE-Q8 proved to be a psychometrically sound and economical self-report assessment tool of eating disorder psychopathology in children. Further validation studies are needed, particularly concerning discriminant and predictive validity.

Neck circumference is similarly predicting for impairment of glucose tolerance as classic anthropometric parameters among healthy and obese children and adolescents

BACKGROUND

The objective of the study was to investigate the association of neck circumference (NC) to parameters of glucose homeostasis compared to classical anthropometric parameters of lean and obese children.

METHODS

Three dimensional (3D)-body scanning quantified anthropometric (height, weight, NC, hip/waist circumference, BMI) and metabolic parameters (fasting plasma glucose [FPG], insulin, HbA1c, oGTT, HOMA-IR) were determined cross-sectionally in 1542 participants (5-18 years).

RESULTS

NC was positively correlated with all metabolic parameters, except for FPG. For HbA1c there was only a modestly positive correlation. The associations between NC and glucose parameters were rather weak, while the correlation to insulin parameters were stronger. Overall the strongest association to glucose metabolism parameters was found for waist circumference (WC), except for FPG and 2h-postload glucose. In multiple linear regression analyses, NC provided additional benefit beyond classical anthropometric indices to describe impairment of glucose homeostasis.

CONCLUSIONS

We suggest that NC is comparable or additive to established anthropometric parameters but might not be superior to them. However NC is simple to measure, reproducible and may be considered in clinical practice as an additional measurement tool.

Validity and intraobserver reliability of three-dimensional scanning compared with conventional anthropometry for children and adolescents from a population-based cohort study

BACKGROUND

Conventional anthropometric measurements are time consuming and require well trained medical staff. To use three-dimensional whole body laser scanning in daily clinical work, validity, and reliability have to be confirmed.

METHODS

We compared a whole body laser scanner with conventional anthropometry in a group of 473 children and adolescents from the Leipzig Research Centre for Civilization Diseases (LIFE-Child). Concordance correlation coefficients (CCC) were calculated separately for sex, weight, and age to assess validity. Overall CCC (OCCC) was used to analyze intraobserver reliability.

RESULTS

Body height and the circumferences of waist, hip, upper arm, and calf had an "excellent" (CCC ≥ 0.9); neck and thigh circumference, a "good" (CCC ≥ 0.7); and head circumference, a "low" (CCC < 0.5) degree of concordance over the complete study population. We observed dependencies of validity on sex, weight, and age. Intraobserver reliability of both techniques is "excellent" (OCCC ≥ 0.9).

CONCLUSION

Scanning is faster, requires less intensive staff training and provides more information. It can be used in an epidemiologic setting with children and adolescents but some measurements should be considered with caution due to reduced agreement with conventional anthropometry.

Immunoassay or LC-MS/MS for the measurement of salivary cortisol in children?

BACKGROUND

Dysregulation of the adrenal cortex has been assessed with measurement of salivary cortisol. So far salivary cortisol is routinely measured with immunoassay (IA). However, liquid chromatography-tandem mass spectrometry (MS) is known to offer better specificity. We compared the concentrations of salivary cortisol measured by MS and IA at basal and stress induced conditions and evaluated reasons for the difference in method-dependent cortisol results.

METHODS

Saliva samples (n=2703) were collected from 169 children (age range: 8-14 years; 81 healthy children; 55 with internalizing and 33 with externalizing disorders) under circadian conditions and during the Trier Social Stress Test for Children (TSST-C). Biochemical analyses were performed with MS for cortisol and cortisone, IA (IBL, RE62011) for cortisol, and enzyme kinetic assay for α-amylase.

RESULTS

MS and IA showed mostly comparable results for circadian activity and TSST-C response with similar statistical power. However, IA measured cortisol concentrations about 2.39-fold higher than MS. We found that this difference in measured values between MS and IA was mainly due to different standardization of IA compared to MS. In addition, at cortisol IA concentration below 5 nmol/L, cross-reactivity with cortisone was found to contribute to the lower concordance between MS and IA.

CONCLUSIONS

Immunoassay and LC-MS/MS were largely comparable in the interpretation of salivary cortisol dynamics in stress research. But the IA method revealed a restricted accuracy in the measuring range below 5 nmol/L.

Self-Esteem of 8-14-Year-Old Children with Psychiatric Disorders: Disorder- and Gender-Specific Effects

In this study, we investigated the relation between global and domain-specific self-esteem and psychiatric disorders. A sample of 577 children aged 8-14 years was recruited via psychiatric hospitals and from the general population. Parents were given a diagnostic interview to assess children's psychiatric diagnoses (current/past). Parents and children completed questionnaires on child symptoms. Children completed a questionnaire on global and domain-specific self-esteem (scales: scholastic competence, social acceptance, athletic performance and physical appearance, global self-esteem). Self-esteem of children with current psychiatric disorders was lower than that of healthy controls (η _p² between 0.01 and 0.08). Concerning scholastic competence, social acceptance and global self-esteem, children with past psychiatric disorders scored also lower than healthy controls. Different current psychiatric disorders showed specific but small effects on dimensions of self-esteem (β between -0.08 and 0.19). Moreover, we found a gender × group interaction, indicating that girls with depressive and adjustment disorders were specifically impaired in their global self-esteem and perception of their physical appearance. Findings might help clinicians to focus on particular domains of self-esteem during the diagnostic process and to define adequate treatment goals.

The LIFE Child study: a population-based perinatal and pediatric cohort in Germany

The LIFE Child study is a large population-based longitudinal childhood cohort study conducted in the city of Leipzig, Germany. As a part of LIFE, a research project conducted at the Leipzig Research Center for Civilization Diseases, it aims to monitor healthy child development from birth to adulthood and to understand the development of lifestyle diseases such as obesity. The study consists of three interrelated cohorts; the birth cohort, the health cohort, and the obesity cohort. Depending on age and cohort, the comprehensive study program comprises different medical, psychological, and sociodemographic assessments as well as the collection of biological samples. Optimal data acquisition, process management, and data analysis are guaranteed by a professional team of physicians, certified study assistants, quality managers, scientists and statisticians. Due to the high popularity of the study, more than 3000 children have already participated until the end of 2015, and two-thirds of them participate continuously. The large quantity of acquired data allows LIFE Child to gain profound knowledge on the development of children growing up in the twenty-first century. This article reports the number of available and analyzable data and demonstrates the high relevance and potential of the study.

Nocturnal levels of chemerin and progranulin in adolescents: influence of sex, body mass index, glucose metabolism and sleep

BACKGROUND

Adipokines have been implicated in obesity, insulin resistance and sleep regulation. However, the role of chemerin and progranulin, two recently described adipokines, in the context of sleep remains unclear. The aim of this study was to compare nocturnal serum chemerin and progranulin levels between overweight/obese and normal-weight adolescents and to assess variations by sex, across different sleep stages and in relation to glucose metabolism.

METHODS

The study sample included 34 overweight/obese and 32 normal-weight adolescents from secondary schools and the Leipzig Research Center for Civilization Diseases (LIFE) Child study cohort. We obtained longitudinal serum adipokine levels during in-laboratory polysomnography followed by an oral glucose tolerance test.

RESULTS

Overweight/obese adolescents had significantly higher mean nocturnal serum chemerin area under the curve (AUC) levels (348.2±133.3 vs. 241.7±67.7 vs. ng/mL×h, p<0.001) compared to normal-weight controls. In detail, higher chemerin AUC levels in obese/overweight subjects were exclusively due to increased levels in females. No overall difference for serum progranulin AUC was found between the groups. However, when assessing sex-specific levels, serum progranulin AUC levels were ~30% higher in overweight/obese males compared to overweight/obese females. Of note, nocturnal serum chemerin and progranulin AUC did not exhibit a correlation with markers of glucose metabolism or sleep stages.

CONCLUSIONS

Collectively, we report a sexual dimorphism in nocturnal progranulin and chemerin levels, which may help explain underlying differences in energy balance and body composition between males and females in the context of obesity.

Serum lipid levels were related to socio-demographic characteristics in a German population-based child cohort

AIM

Socio-demographic factors affect the development and lives of children and adolescents. We examined links between serum lipids and apolipoproteins and socio-demographic factors in the Leipzig Research Centre for Civilization Diseases Child (LIFE Child) study.

METHODS

The Winkler index and the Family Affluence Scale were used to define characteristics of the social status of 938 boys and 860 girls aged from birth to 19 years. We then used univariate and multivariate regression analyses to examine the socio-demographic impact on total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL), cholesterol triglycerides and apolipoproteins A1 (ApoA1) and B (ApoB).

RESULTS

No significant influences on the Winkler index or the Family Affluence Scale were observed regarding the concentrations of serum lipids for total cholesterol or LDL cholesterol. However, and most importantly, children and adolescents with high social status and high family affluence showed significantly higher HDL cholesterol and ApoA1 levels than those with lower individual totals. A higher Winkler index was associated with significantly lower values for triglycerides and ApoB.

CONCLUSION

Adolescents with higher family wealth and social status showed a lower cardiovascular risk profile, as measured by the concentrations of HDL cholesterol and triglycerides as well as ApoA1 and B.

Feeding, eating and behavioral disturbances in Prader-Willi syndrome and non-syndromal obesity

BACKGROUND

Although most individuals with Prader-Willi syndrome (PWS) are obese, little is known about the impact of obesity-related psychosocial factors in PWS. In the present study we compared feeding, eating, and behavioral disturbances in children and adolescents with PWS, peers with non-syndromal obesity, and normal weight controls.

METHODS

Twelve persons with PWS, aged 7-22 years, age- and gender-matched obese and normal weight individuals were analyzed regarding parental feeding practices, eating disturbances, and behavioral problems via standardized questionnaires.

RESULTS

Parents of individuals with PWS reported significantly more restrictive feeding and monitoring than did parents of obese or normal weight children without PWS (p<0.05). Social problems were more common in the obese and the PWS group than in the normal-weight group (p<0.05). Behavioral problems were significantly correlated with parental restrictive feeding practices.

CONCLUSIONS

Our data show that children and adolescents with PWS are affected by psychosocial problems, and that restrictive feeding practices might be associated with more severe behavioral problems. Further studies in larger samples will be necessary to replicate these results and possibly provide new therapeutic approaches for the management of PWS.

Liquid chromatography quadrupole linear ion trap mass spectrometry for quantitative steroid hormone analysis in plasma, urine, saliva and hair

Steroid analysis is being conquered by liquid chromatography tandem mass spectrometry (LC-MS/MS) benefiting from higher standardization, selectivity and diversity. Regarding high throughput in routine diagnostics rapid chromatography is mandatory. Introducing MS(3) (MS/MS/MS), specificity of mass spectrometric detection can be enhanced without sacrificing analysis time. 100mL of human plasma/serum, saliva, urine and 10-20mg of hair are used for the simultaneous quantification of 17α-hydroxyprogesterone, aldosterone, androstenedione, cortisol, cortisone, dehydroepiandrosterone sulfate (DHEAS), estradiol, progesterone, and testosterone using online solid phase extraction (SPE) LC-MS/MS or LC-MS(3). Steroids can be analyzed in 4min after a single manual dilution and protein precipitation step. In complex sample matrices like hair MS(3) detection was found to be appropriate for quantitation. Lower limits of quantitation ranged from 37pmol/L (estradiol) up to 3.1nmol/L (DHEAS). General accuracy was 89-107% with between-run imprecision ≤10%. Comparison to immunoassays revealed significant differences in quantitation for urinary cortisol (-71% mean), aldosterone (-40% mean) and plasma aldosterone (-45% mean). The comparison of MS(2) and MS(3) quantitation of hair cortisol also revealed significant differences. In general, quantitation via MS(3) was not applicable for a long time. But with the current generation of mass spectrometers quantitation via MS(3) can be superior to MS(2) regarding specificity and accuracy when dealing with matrix issues. However, drawbacks regarding flexibility and precision have to be taken into account. Concludingly, simple protein precipitation combined with rapid online SPE LC-MS/MS/MS allows us to quantify over broad, essential concentration ranges in human serum, saliva, urine and hair.

Child Obesity and Mental Health: A Complex Interaction

Prevalence rates of childhood obesity have risen steeply over the last 3 decades. Given the increased national focus, the frequency of this clinical problem, and the multiple mental health factors that coexist with it, make obesity a public health concern. The complex relationships between mental health and obesity serve to potentiate the severity and interdependency of each. The purpose of this review is to create a contextual connection for the 2 conditions as outlined by the research literature and consider treatment options that affect both health problems.

Implementing the K-SADS-PL as a standard diagnostic tool: Effects on clinical diagnoses

Diagnostic interviews are valuable tools for generating reliable and valid psychiatric diagnoses. However, little is known about the diagnostic effects of implementing such an interview into the standard diagnostic procedure of a child psychiatric clinic. Therefore, we reviewed discharge diagnoses of psychiatric patients (age: 8-12 years; combined sample of inpatients and day hospital patients) over two intervals before and after implementing the semi-structured diagnostic interview K-SADS-PL as a diagnostic tool during intake. Each interval was a two year period spanning from 2009-2010 (pre sample; n=177) and from 2012-2013 (post sample; n=132). The number of diagnoses per patient and the co-morbidity rate increased significantly in the post sample. Furthermore, the percentage of children with a nonspecific diagnosis "other mixed disorders of conduct and emotions" (ICD-10: F92.8) decreased significantly after using the K-SADS-PL. Regarding the main diagnostic categories, a significant increase in the number of anxiety disorders and stress-related and somatoform disorders was found in the post sample. The results suggest that implementing a semi-structured interview into the daily routine of child psychiatry may have a substantial impact on discharge diagnoses. Practical implications are discussed and ideas for future research are given.

The hyporeactivity of salivary cortisol at stress test (TSST-C) in children with internalizing or externalizing disorders is contrastively associated with α-amylase

BACKGROUND

Stress biomarkers of the autonomic nervous system and hypothalamic-pituitary-adrenal axis (HPA-axis) can be measured via alpha-amylase (AA) and cortisol and cortisone in saliva. Objectives were to determine 1) the response patterns of cortisol, cortisone, and AA under both circadian conditions and the Trier Social Stress Test for Children (TSST-C), 2) which reactivity index is most suitable to differentiate internalizing or externalizing disorders from controls, and to explore 3) the interaction between AA and cortisol in the presence of internalizing or externalizing disorders.

METHODS

Saliva samples (n = 2893) from children with internalizing (n = 55) or externalizing disorders (n = 33) and healthy children (n = 81) were analyzed for cortisol, cortisone, and AA under circadian conditions and TSST-C.

RESULTS

Circadian rhythm of three biomarkers did not differ between diagnostic groups. Age and gender were significant predictors for cortisol and awakening time influenced all three biomarkers significantly. TSST-C responses appeared sequentially in the order of AA, cortisol, and cortisone. Trajectories of cortisol and cortisone responses, not in AA, were significantly lower in children with internalizing or externalizing disorders than in healthy children. Cortisol percentage increase appeared to be the most suitable reactivity index to detect the difference between the diagnostic groups. Internalizing disorders had a negative association between AA decrease and cortisol increase (β = -.199, p < .05, R(2) = .304). Externalizing disorders had a positive association between AA baseline and cortisol increase (β = .229, p < .05, R(2) = .304).

CONCLUSION

An altered HPA-axis response during stress might result from chronic allostatic load in internalizing disorders and underaroused stress response system in externalizing disorders.

Association between IgE-mediated allergies and diabetes mellitus type 1 in children and adolescents

BACKGROUND

Type 1 diabetes mellitus (T1DM) is characterized by an immunological reaction that is dominated by type-1 T helper (Th1) cells, whereas immunoglobulin E (IgE)-mediated allergies are associated with Th2 cell. According to the Th1/Th2-hypothesis, the immune system is said to either develop into the direction of Th1 or Th2 cells. This would mean that a child developing T1DM is unlikely to develop an IgE-mediated allergy and vice versa.

OBJECTIVE

The aim of the study was to investigate the association between the prevalence of T1DM and IgE-mediated allergies.

METHODS

We designed a prospective case control study with 94 children and adolescents with T1DM and 188 age- and sex-matched control children. The basis of our investigations was a questionnaire concerning the family and children's history as to the presence of IgE-mediated allergies. Moreover, the following blood investigations were done: total serum IgE, specific IgE antibodies to major inhalant allergens, and a multiplex cytokine analysis measuring levels of specific cytokines representing either Th1- or Th2- cytokines.

RESULTS

Children with T1DM reported the presence of IgE-mediated allergies significantly more often than children of the control group. Children with T1DM had significantly higher tumor necrosis factor alpha (TNFα) levels than healthy controls. Levels of interleukin-2 (IL-2) and IL-6 were higher in the groups of children with the presence of a personal history of allergies, regardless of the presence of T1DM.

CONCLUSIONS

Our results suggest that T1DM is associated with a higher risk of a self-reported presence of IgE-mediated allergies and that the Th1/Th2-hypothesis may be an oversimplification.

The acceptance of the K-SADS-PL - potential predictors for the overall satisfaction of parents and interviewers

The presented study investigated the interviewee (parents) and interviewer acceptance of the semi-structured diagnostic interview Kiddie Schedule for Affective Disorders and Schizophrenia for School Aged Children Present Lifetime version (KSADS-PL; German version). Seventeen certified interviewers conducted 231 interviews (interviewers conducted several interviews; interviewees were only questioned once). Interviewees and interviewers anonymously rated their acceptance right after the interview was finished. The nested data structure was analysed regarding an individual interviewer bias and potential predictors of overall satisfaction. Therefore, factors improvable by interviewer training were included, as well as fixed factors which cannot be improved by professional training. The overall satisfaction was evaluated as highly positive with significant higher interviewee and interviewer ratings in the research as compared to the clinical recruitment setting. An individual bias of the interviewer on his or her own acceptance over time, but not on the evaluation of the corresponding interviewee was found. Neither the professional background nor the gender of the interviewer had a significant contribution in predicting these differences. The interviewer model showed no significant change over time and only the interview duration and the interviewee acceptance were significant predictors for interviewer overall satisfaction. Regarding the interviewee model, just the interviewer acceptance was a significant predictor. Copyright Copyright © 2015 John Wiley & Sons, Ltd.

The LIFE-Adult-Study: objectives and design of a population-based cohort study with 10,000 deeply phenotyped adults in Germany

Background

The LIFE-Adult-Study is a population-based cohort study, which has recently completed the baseline examination of 10,000 randomly selected participants from Leipzig, a major city with 550,000 inhabitants in the east of Germany. It is the first study of this kind and size in an urban population in the eastern part of Germany. The study is conducted by the Leipzig Research Centre for Civilization Diseases (LIFE). Our objective is to investigate prevalences, early onset markers, genetic predispositions, and the role of lifestyle factors of major civilization diseases, with primary focus on metabolic and vascular diseases, heart function, cognitive impairment, brain function, depression, sleep disorders and vigilance dysregulation, retinal and optic nerve degeneration, and allergies.

Methods/design

The study covers a main age range from 40-79 years with particular deep phenotyping in elderly participants above the age of 60. The baseline examination was conducted from August 2011 to November 2014. All participants underwent an extensive core assessment programme (5-6 h) including structured interviews, questionnaires, physical examinations, and biospecimen collection. Participants over 60 underwent two additional assessment programmes (3-4 h each) on two separate visits including deeper cognitive testing, brain magnetic resonance imaging, diagnostic interviews for depression, and electroencephalography.

Discussion

The participation rate was 33 %. The assessment programme was accepted well and completely passed by almost all participants. Biomarker analyses have already been performed in all participants. Genotype, transcriptome and metabolome analyses have been conducted in subgroups. The first follow-up examination will commence in 2016.

Early processing of emotional faces in a Go/NoGo task: lack of N170 right-hemispheric specialisation in children with major depression

Emotionally biased information processing towards sad and away from happy information characterises individuals with major depression. To learn more about the nature of these dysfunctional modulations, developmental and neural aspects of emotional face processing have to be considered. By combining measures of performance (attention control, inhibition) in an emotional Go/NoGo task with an event-related potential (ERP) of early face processing (N170), we obtained a multifaceted picture of emotional face processing in a sample of children and adolescents (11-14 years) with major depression (MDD, n = 26) and healthy controls (CTRL, n = 26). Subjects had to respond to emotional faces (fearful, happy or sad) and withhold their response to calm faces or vice versa. Children of the MDD group displayed shorter N170 latencies than children of the CTRL group. Typical right lateralisation of the N170 was observed for all faces in the CTRL but not for happy and calm faces in the MDD group. However, the MDD group did not differ in their behavioural reaction to emotional faces, and effects of interference by emotional information on the reaction to calm faces in this group were notably mild. Although we could not find a typical pattern of emotional bias, the results suggest that alterations in face processing of children with major depression can be seen at early stages of face perception indexed by the N170. The findings call for longitudinal examinations considering effects of development in children with major depression as well as associations to later stages of processing.

The Odense Child Cohort: aims, design, and cohort profile

BACKGROUND

The importance of the environment on the development of the fetus and infant throughout early life is increasingly recognised. To study such effects, biological samples and accurate data records are required. Based on multiple data collection from a healthy pregnant population, the Odense Childhood Cohort (OCC) study aims to provide new information about the environmental impact on child health by sequential follow-up to 18 years of age among children born between 2010 and 2012.

METHODS

A total of 2874 of 6707 pregnancies (43%) were recruited between January 2010 and December 2012. Three hundred seventy-four have since left the study, leaving 2500 active families. The non-participants act as controls contributing data through local registries. Biological material, questionnaires, and registry data were compiled. Anthropometric data and other physical data were collected.

RESULTS

Two thousand five hundred families actively participated in the study with 2549 children. Sixty-four per cent of the fathers and 60% and 58% of the mothers, respectively, donated a blood sample at 10 and 28 weeks of gestation. On average, 69% completed questionnaires, 78% of the children were regularly examined, and had a blood sample taken (46%). The participating pregnant women differed from the non-participants in several respects: age, body mass index, smoking, parity, education, and ethnicity. The infants were comparable with respect to gender and mode of delivery.

CONCLUSIONS

The OCC provides material for in-depth analysis of environmental and genetic factors that are important for child health and disease. Registry data from non-participating women and infants are available which ensures a high degree of comparable data.

Prenatal recruitment of participants for a birth cohort study including cord blood collection: results of a feasibility study in Bremen, Germany

BACKGROUND

Prospective birth cohort studies comprising follow up of children from pregnancy or birth over a long period of time, and collecting various biological samples at different times through the life-course offer a promising approach to enhance etiologic knowledge of various diseases. Especially for those where early lifetime exposures and conditions are thought to play an important role. The collection and storage of biological samples is a critical component in epidemiological studies, notably for research regarding prenatal exposures to various environmental factors as well as for DNA extraction. Our feasibility study for a birth cohort within the scope of etiology of childhood leukemia with prospective sampling of mothers and their future newborns aimed to investigate the willingness of pregnant women to participate in a birth cohort study involving collection of blood and umbilical cord blood samples. The overall aim was to develop practice-based research recommendations for a possible German birth cohort study.

METHODS

The study was conducted in Bremen, Germany, between January 2012 and March 2013. Pregnant women were eligible for recruitment if (i) their expected date of delivery was during the study recruitment phase (September 2012-February 2013), (ii) they planned to give birth at the cooperating hospital's obstetric unit and (iii) their knowledge of the German language was sufficient to understand study materials, details of participation and to fill out the prenatal self-administered questionnaire. Maternal blood and umbilical cord blood samples to be used for later research activities were collected and stored at a stem cell bank already collaborating with the hospital. 22 primary care gynecologists were invited to enroll pregnant women for the study and cooperation with one hospital was established. Expectant women were recruited during the last trimester of pregnancy, either during one of their prenatal care visits at their primary care gynecologist or later on in hospital by the attending obstetricians or project staff.

RESULTS

Of the 22 invited primary care gynecologists requested to enroll pregnant women for the study, 8 gynecologists actually collaborated. A total of 200 eligible women were invited to participate in the study, 48 (24%) of whom agreed. 34 women were enrolled by primary care gynecologists, with one gynecologist enrolling 26 women. Twelve of 14 women recruited via hospitals were enrolled by study staff. A total of 41 women consented to the collection of umbilical cord blood and maternal blood samples, and samples could be stored for 54% of them. Reason for non-participation were the uncertainty whether or not the full study would be conducted and the fact that the participants were not willing to decide for their children whether or not genetic information (cord blood) can be stored for research purposes.

CONCLUSION

Enrolling parents in a birth cohort study that includes biosampling is a challenge, but participation can be improved through close collaboration with primary care gynecologists and maternity hospitals. Cord blood collection may impede participation, especially when maternity hospitals offer an alternative option for cord blood donation.

Babies Galore; or recent findings and future perspectives of pregnancy cohorts with a focus on immunity

Population-based pregnancy cohorts recruiting women before or at the moment of childbirth allow a longitudinal follow-up on children's health later in life. Important findings arising from pregnancy cohorts are discussed in the present review. These insights have led to revised guidelines on how to minimize disease risks in children, e.g., in the context of chronic immune diseases including allergies and asthma. Moreover, insights from pregnancy cohorts also unveiled a collateral effect of pregnancy on maternal immunity, mirrored by an ameliorated course of certain autoimmune diseases, but also an increased risk of infection with influenza A virus. Future pregnancy cohort studies are still required to close gaps in knowledge on how parameters involved in the developmental origin of health or poor immunity observed in children later in life are operational. We discuss here features that should be covered by future pregnancy cohort studies. Expected insights from such studies will then lay the foundation for biomarker discovery and offer opportunities for interventions to ameliorate adverse immune responses in humans.

Uppsala Longitudinal Study of Childhood Obesity: protocol description

BACKGROUND AND OBJECTIVE

The prevalence of childhood obesity has risen considerably on a global scale during the past decades, and the condition is associated with increased risk of morbidity. The objective is to describe the Uppsala Longitudinal Study of Childhood Obesity (ULSCO) cohort, including some baseline data, and outline addressed research areas that aim at identifying factors implicated in and contributing to development of obesity and obesity-related diseases, including type 2 diabetes.

METHODS

Severely obese and lean control subjects are examined at enrollment and at subsequent annual visits by using detailed questionnaires, anthropometric measurements, indirect calorimetry, and functional tests such as oral glucose tolerance tests. Some subjects undergo additional characterization with MRI, subcutaneous fat biopsies, frequent blood sampling, and hyperglycemic clamps. Biological samples are obtained and stored in a biobank.

RESULTS

Active recruitment started in 2010, and standard operating procedures have been established. A high participation rate and annual follow-ups have resulted in a cohort exceeding 200 subjects, including 45 lean controls (as of October 2013). Initial research focus has been on traits of the metabolic syndrome, hyperinsulinemia and identifying risk factors for type 2 diabetes.

CONCLUSIONS

The ULSCO cohort serves as an important resource in defining and understanding factors contributing to childhood obesity and development of obesity-related diseases. Given the comprehensive characterization of the cohort, factors contributing to disease development and progression can be identified. Such factors are further evaluated for their mechanistic role and significance, and noncommunicable metabolic diseases are especially addressed and considered.

Longitudinal follow-up of the relationship between dietary intake and growth and development in the Lifeways cross-generation cohort study 2001-2013

In this paper we will review evidence on the early life and familial influences on childhood growth and development, with particular reference to the Lifeways cross-generation cohort study in the Republic of Ireland. The Lifeways cross-generation cohort study was established in 2001-2013 through two maternity hospitals in the Republic of Ireland and was one of many new cohort studies established worldwide in the millennium period. Mothers were recruited at first booking visit, completing a self-administered questionnaire, which included a 147 item semi-quantitative FFQ. Longitudinal follow-up is ongoing in 2013, with linkage data to hospital and general practice records and examination of children when aged 5 and 9 years. The study is one of very few containing data on grandparents of both lineages with at least one grandparent recruited at baseline. There have been consistent associations between parental and grandparental health status characteristics and children's outcomes, including infant birth-weight, BMI when child was aged 5 years and childhood wheeze or asthma when child was aged 3 and aged 5 years. In conclusion, empirical evidence to date shows consistent familial and cross-generational patterns, particularly in the maternal line.

Medical and psychosocial implications of adolescent extreme obesity - acceptance and effects of structured care, short: Youth with Extreme Obesity Study (YES)

Background

Prevalence rates of overweight and obesity have increased in German children and adolescents in the last three decades. Adolescents with extreme obesity represent a distinct risk group. On the basis of data obtained by the German Child and Youth Survey (KiGGS) and the German district military offices we estimate that the group of extremely obese adolescents (BMI ≥ 35 kg/m²) currently encompasses approximately 200.000 adolescents aged 14 to 21 yrs. Conventional approaches focusing on weight reduction have largely proven futile for them. In addition, only a small percentage of adolescents with extreme obesity seek actively treatment for obesity while contributing disproportionately strong to health care costs. Because of somatic and psychiatric co-morbidities and social problems adolescents with extreme obesity require special attention within the medical care system.

We have initiated the project “Medical and psychosocial implications of adolescents with extreme obesity - acceptance and effects of structured care, short: ‘Youths with Extreme Obesity Study (YES)’”, which aims at improving the medical care and social support structures for youths with extreme obesity in Germany.

Methods/Design

We focus on identification of these subjects (baseline examination) and their acceptance of diagnostic and subsequent treatment procedures. In a randomized controlled trial (RCT) we will investigate the effectiveness of a low key group intervention not focusing on weight loss but aimed at the provision of obesity related information, alleviation of social isolation, school and vocational integration and improvement of self-esteem in comparison to a control group treated in a conventional way with focus on weight loss. Interested individuals who fulfill current recommended criteria for weight loss surgery will be provided with a structured preparation and follow-up programs. All subjects will be monitored within a long-term observational study to elucidate medical and psychosocial outcomes. Our aim is to evaluate realistic treatment options. Therefore inclusion and exclusion criteria are minimized.

We will recruit adolescents (age range 14–21 years) with extreme obesity (BMI ≥ 35 kg/m²) (extreme group) within 24 months (120 per centre, 5 centres) as well as obese adolescents being at risk for developing extreme obesity (BMI ≥ 30 – 34.9 kg/m²) (at risk group). Follow-up evalutations will be performed biannually after inclusion for several years depending on additional funding. In sum, we aim at establishing evaluated health care structures for extremely obese adolescents.

Discussion

The results of YES will be of importance for a frequently neglected group of individuals, for whom current medicine has little to offer in terms of structured access to empirically evaluated therapeutic programs. Thus, the results will be both a help for the adolescents within the study and for others in the future given that the trial will lead to a positive finding. Moreover, it will help practitioners and therapists to deal with this neglected group of individuals.

Trial registration

Project registration numbers for each subproject: 1.) ClinicalTrials.gov: NCT01625325, NCT01703273, NCT01662271, NCT01632098; 2.) Germanctr.de: DRKS00004172, DRKS00004195, DRKS00004198, DRKS00004197.