Relation between socioeconomic status and maternal serum lipids to infant lipid concentrations and anthropometry in the first year of life.

PURPOSE: The physical health and development of an individual are influenced by multiple parameters and shaped by internal and external factors during pregnancy. However, it is unclear whether there is an association between maternal lipid concentrations in the third trimester of pregnancy and infant serum lipids as well as anthropometric growth, and whether these factors are influenced by the socioeconomic status (SES) of the mothers. METHODS: Between 2011 and 2021, 982 mother-child pairs were recruited in the LIFE-Child study. To investigate the influence of prenatal factors, pregnant women at the 24th and 36th week of gestation as well as children at the age of 3, 6 and 12 months were examined and serum lipids determined. Socioeconomic status (SES) was assessed using the validated Winkler Index. RESULTS: A higher maternal BMI was associated with a significantly lower Winkler score and a higher infant weight, height, head circumference and BMI from birth up to the 4th-5th week of life. In addition, the Winkler Index correlates with maternal HDL cholesterol and ApoA1 levels. There was no relation between the delivery mode and the maternal BMI or SES. For the maternal HDL cholesterol concentration in the third trimester, an inverse relation to children's height, weight, head circumference and BMI up to the first year of life as well as the chest and abdominal circumference to an age of 3 months was found. Children born to mothers with dyslipidemia in pregnancy tended to have a worse lipid profile than those born to normolipidemic mothers. CONCLUSION: Serum lipid concentrations and anthropometric parameters of children in the first year of life are affected by multiple factors like maternal BMI, lipid levels and SES.

Children's satisfaction with a comprehensive study program-Results from the LIFE Child cohort study.

BACKGROUND: Research participants' satisfaction is a topic of great interest, especially in the context of longitudinal studies. Evaluation also represents an important component of quality management in the health care system. Adult studies found that personal characteristics, e.g., age, sex, ethnicity, and SES, can influence satisfaction with health care or study participation. Studies on paediatric participants are sparse. OBJECTIVES: To examine how children rated the study day of a cohort study and how these ratings were associated with sociodemographic and socioeconomic characteristics and retention in the context of a large cohort study. METHODS: Analyses were performed on 4- to 17-year-old participants of the German longitudinal cohort study LIFE Child (n = 2033). To assess the associations between overall satisfaction (high versus low/middle) and age, sex, body-mass index, socioecomonic status, and participation in a follow-up visit, we applied logistic mixed-effects models. RESULTS: Participants' overall satisfaction with the LIFE Child study day was high ("very good": 67.8%). Overall satisfaction was higher in 7-9 years olds (odds ratio [OR] 2.00, 95% confidence interval [CI 1.51, 2.66) and 10-12 years olds (OR 1.51, 95% CI 1.16, 1.98) than in 4-6 years olds and 13-17 years olds. Children with obesity were less likely to participate in a follow-up visit (OR 0.56, 95% CI 0.39, 0.78). Children reporting high overall satisfaction at the first study visit completed a follow-up visit more frequently (OR 1.32, 95% CI 1.05,1.67). CONCLUSIONS: A high level of satisfaction increased participants' attendance at a follow-up visit. Our results might be helpful for adapting the study program to the participants' needs in order to maximise retention and minimise attrition rates.

Pediatric percentiles for transient elastography measurements - effects of age, sex, weight status and pubertal stage.

Background and aims: Transient Elastography is a non-invasive, cost-efficient, non-ionizing, observer-independent and reliable method to detect liver fibrosis using Liver Stiffness Measurement (LSM) and the degree of fat accumulation in the liver using Controlled Attenuation Parameter (CAP). This study aims to derive reference values for both measures from healthy children and adolescents. Further, we aim to assess the potential influence of age, sex, puberty, and BMI-SDS on CAP and LSM. Methods: Within the LIFE Child study, amongst others, anthropometric data and pubertal status were assessed. Transient Elastography (TE) was performed using the FibroScan® device in a population-based cohort at 982 study visits of 482 healthy children aged between 10 and 18 years. Percentiles for LSM and CAP were estimated, and the effects of age, sex, puberty and weight status were assessed through hierarchical regression models. Results: There was a strong age dependency for LSM with higher values for older children, most pronounced in the upper percentiles in boys. Contrarily, CAP was relatively stable across the age span without considerable difference between boys and girls. We found a significant positive correlation between BMI-SDS and both CAP and LSM for BMI-SDS >1.28. For BMI-SDS < 1.28, the association was also positive but reached statistical significance only for CAP. Further, the association between BMI-SDS and CAP was significantly stronger in younger than in older children. There was no association between pubertal status and CAP. For LSM, we found that children with a high BMI-SDS but not children with normal weight had significantly higher LSM values in Tanner stage 4. Conclusions: Age, sex, pubertal status and weight status should be considered when interpreting LSM and CAP in pediatric patients to facilitate and improve early detection of abnormal liver function, which is associated with common pathologies, such as NAFLD.

Substance use in childhood and adolescence and its associations with quality of life and behavioral strengths and difficulties.

BACKGROUND: Substance use in childhood and adolescence continues to be a current health concern. The aims of the present study were to identify trends in the use of alcohol, cigarettes, and cannabis in children and adolescents in the last 10 years and to assess associations between substance use and quality of life and behavioral strengths and difficulties. METHODS: Substance use was examined in 1829 9- to 18-year-old German children and adolescents participating in the LIFE Child cohort study between 2011 and 2020. Quality of life was investigated using the KIDSCREEN-27 questionnaire. The Strength and Difficulties Questionnaire was used to assess behavioral strengths and difficulties. Associations were assessed using linear regression analyses. All effects were adjusted for age, gender, and family socio-economic status. RESULTS: 38.44% of participants reported drinking alcohol at least sometimes. Smoking (6.23%) and the use of cannabis (3.94%) were less frequent. While we observed no significant changes in smoking between 2011 and 2021, the consumption of cannabis and the frequent consumption of alcohol has increased in this time period. Cigarette and cannabis use were associated with additional symptoms of hyperactivity/inattention and reduced prosocial behavior. For all three substances, usage was associated with more conduct problems. We also found significant associations between substance use and a lower quality of life in the areas of physical wellbeing, psychological wellbeing, parent relation and autonomy, and school environment. One noteworthy finding was that cigarette consumption and frequent alcohol use were associated with higher quality of life in terms of social support/peer group relations. Some significant interactions between substance use and child age indicated that associations between substance use and quality of life or behavioral difficulties were stronger in younger than in older children. CONCLUSIONS: The results show that quality of life and behavioral difficulties are associated with substance use and should be considered when developing or implementing preventive measures to counter substance use. Furthermore, the findings indicate that substance use can be accompanied by improved peer relations. Therefore, the influence of peers, especially of peers who use these substances, should not be underestimated.

Associations of media use and early childhood development: cross-sectional findings from the LIFE Child study.

BACKGROUND: Excessive media usage affects children's health. This study investigated associations between children's and mother's media use, parent-child interactions, and early-childhood development outcomes. METHODS: Two hundred and ninety-six healthy 2-5-year-old preschoolers (52.4% male, mean age = 3.5 years) and 224 mothers from the LIFE Child cohort study were analyzed. Screen times and parent-child interactions were assessed using standardized parental questionnaires. Developmental skills were investigated using the standardized development test ET 6-6-R. RESULTS: High screen times in children (>1 h/day) were significantly associated with lower percentile ranks in cognition (b = -10.96, p < 0.01), language (b = -12.88, p < 0.01), and social-emotional skills (b = -7.80, p = 0.05). High screen times in mothers (>5 h/day) were significantly associated with high media use by children (OR = 3.86, p < 0.01). Higher parent-child interaction scores were significantly associated with better body motor (b = 0.41, p = 0.05), cognition (b = 0.57, p < 0.01), language (b = 0.48, p = 0.02), and social-emotional outcomes (b = 0.80, p < 0.01) in children. CONCLUSIONS: Public health strategies should seek to educate caregivers as competent mediators for their children's media habits, with focus on the need for children to have frequent parent-child interactions. IMPACT: High media usage in children is related to poorer cognition, language, and social-emotional skills. More frequent parent-child interactions are associated with better body motor, cognition, language, and social-emotional skills in children. High level of media use in mothers is not directly related to children's development outcomes but is directly related to high media usage of children. Public health strategies should seek to raise media awareness and management in both parents and children.

Concentrations of oligosaccharides in human milk and child growth.

BACKGROUND: The relationship between human milk oligosaccharides (HMO) and child growth has been investigated only insufficiently with ambiguous results. Therefore, this study examines potential influencing factors of HMO concentrations and how HMO are associated with child growth parameters. METHODS: Milk samples from the German LIFE Child cohort of healthy children were analyzed for 9 HMO. Putative associations with maternal and child cofactors and child height, head circumference and BMI between 3 months and 7 years of age were examined. Secretor status, defined as the presence of 2'-fucosyllactose, was investigated for associations with infant outcomes. RESULTS: Our population consisted of 21 (14.7%) non-secretor and 122 (85.3%) secretor mothers. Maternal age was significantly associated with higher 3'SL concentrations; gestational age was associated with LNT, 6'SL and LNFP-I. Pre-pregnancy BMI was negatively associated with LNnT only in non-secretors. The growth velocity of non-secretors' children was inversely associated with LNnT at 3 months to 1 year (R = 0.95 [0.90, 0.99], p = 0.014), 1 to 2 years (R = 0.80 [0.72, 0.88], p < 0.001) and 5 to 6 years (R = 0.71 [0.57, 0.87], p = 0.002). 2'FL was negatively associated with BMI consistently, reaching statistical significance at 3 months and 4 and 5 years. Children of non-secretors showed higher BMI at 3 months, 6 months, and 3, 6, and 7 years of age. CONCLUSION: We found that some associations between HMO and infant growth may extend beyond the infancy and breastfeeding periods. They highlight the importance of both maternal and infant parameters in the understanding of the underlying associations. TRIAL REGISTRATION: The study is registered with ClinicalTrial.gov: NCT02550236 .

Motor skills in relation to body-mass index, physical activity, TV-watching, and socioeconomic status in German four-to-17-year-old children.

BACKGROUND: The present study describes motor skills in a large sample of German children and adolescents and investigates associations with age, gender, body-mass index, physical activity, television time, and socioeconomic status. METHODS: 2,106 children (1076 boys, 1030 girls) aged 4 to 17 years performed five different motor tests for strength (pushups, standing long jump), coordination (backward balancing, jumping side-to-side) and flexibility (forward bend) within the framework of the LIFE Child study (Leipzig, Germany). Anthropometric parameters were assessed through standardized measurement. Data on physical activity, television time, and socioeconomic status were collected via questionnaires. Linear regression analyses were applied to assess relations. RESULTS: Strength and coordination performance were higher in older than in younger children. While boys showed a higher performance in strengths tests than girls, girls performed better in flexibility and coordination during precision tasks (backward balancing). In terms of coordination under time constraint (jumping side-to-side), both genders produced similar results. Lower body-mass index, higher physical activity, and higher socioeconomic status were significantly related to better motor skills. Longer television times were significantly associated with lower performance in long jump. CONCLUSIONS: The present findings are similar to data collected at the beginning of the century, indicating that motor skills have hardly changed in recent years. The findings furthermore suggest that children from lower social strata, children with higher body weight, and children who move little have a higher risk of developing insufficient motor skills and should therefore be given special support.

Leisure Activities of Healthy Children and Adolescents.

The objective of the present study was to give a detailed overview on the leisure behavior of adolescents (frequency, differences between gender, age groups and social class, time trends, and inter-relations). In total, 1449 10- to 18-year-old German adolescents were included in the study. Participants answered questionnaires about their media use, physical activity, outdoor time, engagement in choir/orchestra and theater/dancing, social life and socio-economic status (SES). The results revealed that girls, children with lower SES as well as older children reported to use screen-based media more often and that girls, older children and children with lower SES were less physically active. In addition, boys and children with lower SES engaged less frequently in choir/orchestra and theater/dancing, while children with higher SES met their friends more often. The time trend analysis showed that mobile phone use increased drastically from 2011 to 2017, while engagement in choir/orchestra and theater/dancing decreased. Regarding the inter-relation between leisure activities, high screen times were significantly associated with less physical activity and less outdoor time. Physical activity, in contrast, was significantly related to better social life and more outdoor time. These findings highlight the growing importance of electronic media in adolescents' lives and their tendency to displace other leisure activities.

Age- and Sex-Related Percentiles of Skinfold Thickness, Waist and Hip Circumference, Waist-to-Hip Ratio and Waist-to-Height Ratio: Results from a Population-Based Pediatric Cohort in Germany (LIFE Child).

BACKGROUND: Skinfold thickness (ST), waist circumference (WC) and hip circumference (HC) measurements are simple methods for assessing fat tissue at defined body parts. We examined these parameters in a cohort of healthy children and adolescents in Leipzig. Our study provides current percentile curves for biceps, triceps, subscapular and iliac crest ST, plus WC, HC, waist-to-hip ratio and waist-to-height ratio. METHODS: 6,344 visits were recorded involving 2,363 individuals from 3 to 16 years in age. Continuous age- and gender-related percentiles (3rd, 10th, median, 90th, 97th percentiles) were estimated using Cole's LMS method. RESULTS: For biceps and triceps ST, boys show a peak at the beginning of adolescence with a subsequent decrease, while percentile values among girls rise across the age range. Subscapular and iliac crest percentiles also show increasing curves with disproportionately high values for P90 and P97. Boys show higher values of WC, girls have higher levels of HC. WC and HC median percentiles constantly increase in both sexes with a plateau at the age of 16 for girls. CONCLUSION: Trends for all parameters of body fat are in line with other national and international studies. Unlike the KiGGS study, our study provides circumference data across the whole of our age range, i.e. from 3 to 16 years.

Reciprocal Longitudinal Associations Between Adolescents' Media Consumption and Psychological Health.

OBJECTIVE: This study investigated reciprocal longitudinal associations between media use/physical activity and adolescents' psychological health. METHODS: Data were collected between 2011 and 2017 in the LIFE Child study in Germany. The sample included 814 10- to 17-year-old adolescents. The participants provided information on their media use per day (hours of television/video, computer/Internet, and mobile phone use), physical activity (frequency of organized and non-organized physical activity per week), behavioral difficulties (emotional problems, conduct problems, hyperactivity/inattention, peer relationship problems), and quality of life (physical and psychological well-being; satisfaction with parents, peers, and school) at 2 time points 12 months apart. Multiple regressions were applied to analyze reciprocal longitudinal associations between media use/physical activity and behavioral difficulties/quality of life. RESULTS: Frequent use of computers/Internet at baseline was associated with an increase in internalizing behavioral difficulties (emotional problems and peer relationship problems) at follow-up. Additionally, a high frequency of computer/Internet and mobile phone use was related to a decrease in psychological well-being, whereas a high frequency of organized physical activity was linked to improved physical well-being. The analyses also revealed a link between more behavioral difficulties at baseline and increased television consumption at follow-up. CONCLUSION: This study suggests mutual dependencies between electronic media use and psychological health over time.

Direct selection of antibodies from complex libraries with the protein fragment complementation assay.

The aim of the present study was to develop the protein fragment complementation assay (PCA) for the intracellular selection of specific binding molecules from the fully synthetic HuCAL antibody library. Here, we describe the first successful selections of specific antibodies by PCA, and we discuss the opportunities and limitations of this approach. First, we enriched an antibody specific for the capsid protein D of bacteriophage lambda (gpD) by ten successive rounds of competitive liquid culture selection. In an independent approach, we selected a specific antibody for the c-Jun N-terminal kinase 2 (JNK2) in a single-step selection setup. In order to obtain specific antibodies in only a single PCA selection round, the selection system was thoroughly investigated and several strategies to reduce the amount of false positives were evaluated. When expressed in the cytoplasm of Escherichia coli, the PCA-selected scFv antibody fragments could be purified as soluble and monomeric proteins. Denaturant-induced unfolding experiments showed that both antibody fragments are stable molecules, even when the disulfide bonds are reduced. Furthermore, antigen-specificity of the PCA-selected antibody fragments is demonstrated by in vivo and in vitro experiments. As antigen binding is retained regardless of the antibody redox state, both PCA-selected antibody fragments can tolerate the loss of disulfide bridge formation. Our results illustrate that it is possible to select well-expressed, stable, antigen-specific, and intracellular functional antibodies by PCA directly.

Ribosome display of mammalian receptor domains.

Many mammalian receptor domains, among them a large number of potential therapeutic target proteins, are highly aggregation-prone upon heterologous expression in bacteria. This severely limits functional studies of such receptor domains and also their engineering towards improved properties. One of these proteins is the Nogoreceptor, which plays a central role in mediating the inhibition of axon growth and functional recovery after injury of the adult mammalian central nervous system. We show here that the ligand binding domain of the Nogoreceptor folds to an active conformation in ternary ribosomal complexes, as formed in ribosome display. In these complexes the receptor is still connected, via a C-terminal tether, to the peptidyl tRNA in the ribosome and the mRNA also stays connected. The ribosome prevents aggregation of the protein, which aggregates as soon as the release from the ribosome is triggered. In contrast, no active receptor was observed in phage display, where aggregation appears to prevent incorporation of the protein into the phage coat. This strategy sets the stage for rapidly studying defined mutations of such aggregation-prone receptors in vitro and to improve their properties by in vitro evolution using the ribosome display technology.