Associations between gestational weight gain and weight development of the offspring: Differences depending on maternal pre-pregnancy BMI

PURPOSE

Obesity rates are rising, and the gestational weight gain (GWG) of most women does not comply with current guidelines. This study assesses the association of pre-pregnancy BMI (ppBMI) and GWG with the child's weight development and investigates whether associations with GWG differ depending on ppBMI.

METHODS

Data were obtained from the cohort study LIFE Child (Germany), comprising 691 mother-child pairs. Children's weight was followed until age five. Associations between maternal ppBMI, GWG, and children's weight were evaluated using regression analyses.

RESULTS

The association between GWG and birth weight (BW) was significantly positive in normal and underweight (n/u) women (βGWG = 0.05, p < 0.01, 95% confidence interval (CI) 0.03-0.07), but not in women with overweight or obesity (o/o) (βGWG = 0.0002, p = 0.99, 95% CI -0.03 to 0.03). The risk of giving birth to an infant who was large for gestational age (LGA) increased with rising GWG in n/u women (OR = 1.6, p < 0.01, 95% CI 1.23-2.25). Women with o/o were at increased risk for a LGA baby regardless of GWG (OR = 3, p < 0.01, 95% CI 1.34-6.97). This trend persisted in the child's weight development during the first 5 years of life.

CONCLUSION

Women with o/o might increase their offspring's risk for higher weight at birth and in early childhood. In n/u women, GWG might be the more influential factor. Women should strive for normal weight before conception and should be more attentive to GWG.

Parent-perceived recurrent pain in children: associations with maternal pain, depressiveness, socioeconomic status, and children's behavioural difficulties

Objectives

The current study aimed to examine the potential transgenerational associations between maternal pain and depressiveness and childhood pain, and to explore the associations between the children's difficulties and recurrent pain (defined as pain occurring at least once a month in the previous 6 month) in healthy children aged 3-13 years.

Methods

We collected Data between 2015 and 2019 as part of the LIFE Child study in Germany and investigated associations of maternal pain and depressiveness, child age, sex, pubertal stage, emotional difficulties, conduct difficulties, hyperactivity/inattention, peer group difficulties, and prosocial skills, and family socioeconomic status with the frequency of parent-perceived headache, backache, and stomachache in a sample of 1,850 children (4,819 documented visits) using logistic and ordinal regression analyses.

Results

Overall, 10.4%, 24.4%, and 45.2% of parents reported their children had recurrent backache, headache, and stomachache, respectively, with 5.5% of children were reported to experience all three types of pain simultaneously. Higher age, female sex, puberty, emotional difficulties, low family socioeconomic status, as well as higher maternal impairment due to pain and maternal depressiveness were significantly associated with more frequent pain.

Conclusions

Our study suggests that maternal pain, maternal depressiveness, and lower family socioeconomic status as well as child's emotional difficulties are significantly associated with a higher frequency of recurrent pain in children perceived by their parents.

X-chromosome and kidney function: evidence from a multi-trait genetic analysis of 908,697 individuals reveals sex-specific and sex-differential findings in genes regulated by androgen response elements

X-chromosomal genetic variants are understudied but can yield valuable insights into sexually dimorphic human traits and diseases. We performed a sex-stratified cross-ancestry X-chromosome-wide association meta-analysis of seven kidney-related traits (n = 908,697), identifying 23 loci genome-wide significantly associated with two of the traits: 7 for uric acid and 16 for estimated glomerular filtration rate (eGFR), including four novel eGFR loci containing the functionally plausible prioritized genes ACSL4, CLDN2, TSPAN6 and the female-specific DRP2. Further, we identified five novel sex-interactions, comprising male-specific effects at FAM9B and AR/EDA2R, and three sex-differential findings with larger genetic effect sizes in males at DCAF12L1 and MST4 and larger effect sizes in females at HPRT1. All prioritized genes in loci showing significant sex-interactions were located next to androgen response elements (ARE). Five ARE genes showed sex-differential expressions. This study contributes new insights into sex-dimorphisms of kidney traits along with new prioritized gene targets for further molecular research.

Associations between sleep problems and emotional/behavioural difficulties in healthy children and adolescents

OBJECTIVE

This study aimed to (1) characterise sleep disturbances and emotional/behavioural difficulties among healthy German children and adolescents aged 3 to 13 years, (2) examine the association between parent-reported sleep problems and emotional/behavioural difficulties, (3) point out possible relations between specific kinds of sleep disturbances and different behavioural difficulties.

METHODS

Data were collected between 2011 and 2015 within the LIFE Child study in Germany. The sample included 1101 3- to 13-year-old children and adolescents. Information on sleep disturbances-assessed via the Children's Sleep Habits Questionnaire (CSHQ), emotional/behavioural difficulties-assessed via the Strengths and Difficulties Questionnaire (SDQ), and socioeconomic status was provided by participants' parents. Multiple regressions were applied to analyse the associations between general and specific sleep disturbances (independent variables) and emotional/behavioural difficulties (dependent variables).

RESULTS

The total CSHQ score was positively associated with the total SDQ score and all SDQ subscales (emotional problems, conduct problems, hyperactivity/inattention, peer relationship problems). Most of the CSHQ subscales were related to SDQ subscale scores, except for a few non-significant relations with hyperactivity/inattention and conduct problems. The CSHQ total score, daytime sleepiness, sleep duration and parasomnias showed the strongest associations with the SDQ total score.

CONCLUSION

This study confirms an association between children's and adolescents' sleep habits and psychological health. We were able to demonstrate the association between sleep problems and emotional/behavioural difficulties in a large sample of healthy participants. In particular, we observed a significant relation between parasomnias and hyperactive/inattentive behaviour as well as a significant association between emotional problems and sleep problems, especially daytime sleepiness, sleep anxiety and parasomnias.

Early child development and its determinants: Findings from a large cohort of healthy children growing up in a low-risk environment

BACKGROUND

Despite numerous studies on early child development, there is still much to be discovered about the significance of possible risk factors. This study examines cognitive, motor, and language development of healthy children growing up in a low-risk environment and how various individual and environmental factors are associated with it. The study also considers whether the importance of particular parameters changes depending on child age.

METHODS

Within the framework of the LIFE Child study in Leipzig, Germany, 481 children participated in a total of 832 visits between 1 and 36 months of age. Developmental status was assessed using the Third Edition of the Bayley Scales of Infant and Toddler Development. Linear regression analyses were applied to examine the associations between child development and sex, gestational age, birth weight, birth mode, overweight, height, and parental education.

RESULTS

Mean Bayley composite scores for cognitive, language, and motor development were close to the standard value of 100. Poorer developmental outcomes were significantly associated with lower gestational age, vacuum cup/forceps birth, being overweight, small height, and lower parental education, although some of the associations became insignificant after applying multivariate models. While the association between gestational age and language development became weaker with advancing age, our interaction models found disparities related to parental education to become more apparent in older children across all three domains of early child development.

CONCLUSIONS

Several factors were identified to be associated with early child development. As children grow older, obstetric parameters, for example, gestational age, might become less relevant compared with sociodemographic factors, for example, parental education.

Family structure, socioeconomic status, and mental health in childhood

The changing landscape of family structures over the last decades has led to a growing need to investigate its impact on children's well-being. This study examined differences in mental health among children from different family compositions and how these differences may be affected by familial socioeconomic status (SES). Data were collected within the LIFE Child study. Participants included 2828 children aged 3-17 years raised in traditional families, stepfamilies, or single-parent families. Mental health was measured using the Strengths and Difficulties Questionnaire (SDQ (behavioral strengths and difficulties)) and the KIDSCREEN-27 questionnaire (quality of life). Linear regression analyses were applied to examine associations between family structure, SES, and mental health outcomes. Children from single-parent families exhibited worse mental health outcomes than those from traditional families across all domains of the SDQ and the KIDSCREEN-27. Children from stepfamilies showed significantly higher Total Difficulties scores (B = 1.29 and 1.42), with 3- to 10-year-olds displaying higher scores in the Hyperactivity & Inattention (B = 0.61) and Peer Relationship Problems (B = 0.36) subscales, and 11- to 17-year-olds showing higher Conduct Problems (B = 0.31), Emotional Symptoms (B = 0.58), and a worse Parent Relationship scores (B = - 1.82) than children from traditional families (all p < 0.05). After controlling for SES, several associations between family structure and mental health lost significance, while others persisted, particularly among older children. To promote mental health in non-traditional families, interventions should address socioeconomic disparities while also investigating factors contributing to the direct impact of family structure on mental well-being.Trial registration The LIFE Child study is registered on clinicaltrials.gov (No. NCT02550236).

Body image and behavioural and emotional difficulties in German children and adolescents

BACKGROUND

Behavioural and emotional difficulties might play an important role in the development of body image disturbances, which represent serious risk factors for eating disorders or depression. The present study provides a detailed overview on body image disturbances and several behavioural and emotional difficulties (differences between gender, age, and weight status) and their inter-relations in German children and adolescents.

METHODS

Data on body image disturbances, assessed through a Figure Rating Scale, and on behavioural and emotional difficulties, assessed through Goodman's Strengths and Difficulties Questionnaire (SDQ), were available for 5255 observations of 1982 German children and adolescents aged 8 to 18 years from the LIFE Child study, based in Leipzig, Germany. Associations were investigated using multiple logistic regression. Each association was checked for interaction with gender, age, and weight status.

RESULTS

Boys reported more behavioural difficulties than girls, while girls reported more emotional difficulties. Gender, age and weight status were related to behavioural and emotional difficulties as well as body image disturbances. Individuals with fewer difficulties were more satisfied with their own body. Children and adolescents who desired to be larger showed more prosocial behaviour problems, conduct and emotional problems and more signs of hyperactivity. Those, who desired to be thinner showed more problems in all SDQ-subscales. A more accurate body size perception was associated with fewer behavioural and emotional difficulties. Children and adolescents who overestimated their body size showed more prosocial behaviour and emotional problems. Underestimation one's body size was associated with more signs of hyperactivity.

CONCLUSION

The current findings highlight the importance of raising the awareness about the association between behavioural and emotional difficulties and body image disturbances in children and adolescents to prevent negative outcomes.

Epigenome-Wide Meta-analysis Reveals Associations Between Dietary Glycemic Index and Glycemic Load and DNA Methylation in Children and Adolescents of Different Body Sizes

OBJECTIVE

Dietary glycemic index (GI) and glycemic load (GL) are associated with cardiometabolic health in children and adolescents, with potential distinct effects in people with increased BMI. DNA methylation (DNAm) may mediate these effects. Thus, we conducted meta-analyses of epigenome-wide association studies (EWAS) between dietary GI and GL and blood DNAm of children and adolescents.

RESEARCH DESIGN AND METHODS

We calculated dietary GI and GL and performed EWAS in children and adolescents (age range: 4.5-17 years) from six cohorts (N = 1,187). We performed stratified analyses of participants with normal weight (n = 801) or overweight or obesity (n = 386). We performed look-ups for the identified cytosine-phosphate-guanine (CpG) sites (false discovery rate [FDR] <0.05) with tissue-specific gene expression of 832 blood and 223 subcutaneous adipose tissue samples from children and adolescents.

RESULTS

Dietary GL was positively associated with DNAm of cg20274553 (FDR <0.05), annotated to WDR27. Several CpGs were identified in the normal-weight (GI: 85; GL: 17) and overweight or obese (GI: 136; GL: 298; FDR <0.05) strata, and none overlapped between strata. In participants with overweight or obesity, identified CpGs were related to RNA expression of genes associated with impaired metabolism (e.g., FRAT1, CSF3).

CONCLUSIONS

We identified 537 associations between dietary GI and GL and blood DNAm, mainly in children and adolescents with overweight or obesity. High-GI and/or -GL diets may influence epigenetic gene regulation and thereby promote metabolic derangements in young people with increased BMI.

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.

Associations between changes in behavioral difficulties and levels of problematic smartphone use in adolescents over a 1-year period

OBJECTIVES

The present longitudinal study investigates associations between changes in externalizing and internalizing behavioral difficulties and changes in problematic smartphone usage within the same 1-year period in healthy adolescents.

METHODS

The project is part of the LIFE Child cohort study conducted in Leipzig, Germany. Ten- to 16-year-old adolescents (n = 363) provided information on behavioral difficulties [Strengths and Difficulties Questionnaire (SDQ)], the duration of daily smartphone use, and symptoms of smartphone addiction [Smartphone Addiction Proneness Scale (SAPS)] at two consecutive study visits, t1 and t2 (1 year after t1). In the first of two analysis phases, we applied linear regression analyses to assess cross-sectional associations between externalizing and internalizing behavioral difficulties and the duration of smartphone use and symptoms of smartphone addiction (at t1 and t2). In the second, we assessed associations between the changes measured in these variables over the period of a year. All associations were adjusted for age, sex, and soci-economic status.

RESULTS

Children who reported prolonged periods of smartphone use or more symptoms of smartphone addiction exhibited significantly higher levels of externalizing and internalizing behavioral difficulties at t1 and t2. Further, children who increased their usage or developed addiction symptoms between t1 and t2 also developed more externalizing behavioral difficulties. We found the same tendencies in regard to internalizing behavioral difficulties, although the associations did not reach statistical significance.

CONCLUSIONS

The present findings suggest that externalizing behavioral difficulties and problematic smartphone use are mutually dependent in the long term.

Media regulation strategies in parents of 4- to 16-year-old children and adolescents: a cross-sectional study

BACKGROUND

Since children can only control and limit their own media use to a limited extent, it is often the parents who regulate their children's media use. However, there is insufficient research on which strategies they use and on how these strategies are related to socio-demographic and behavioral parameters.

METHODS

The parental media regulation strategies co-use, active mediation, restrictive mediation, monitoring, and technical mediation were assessed in a sample of 563 four- to 16-year-old children and adolescents from middle to high social strata participating in the German cohort study LIFE Child. We investigated cross-sectional associations with socio-demographic characteristics (age and sex of child, age of parent, and socio-economic status (SES)) and other behavioral parameters of children (media use, ownership of media devices, engagement in extracurricular activities) and their parents (media use).

RESULTS

All media regulation strategies were applied frequently, with restrictive mediation occurring most frequently. Overall, parents of younger children and of boys mediated media use more frequently, while we observed no differences depending on SES. Regarding child behavior, the ownership of a smartphone and a tablet/personal computer/laptop was associated with more frequent technical restriction, while screen time and engagement in extracurricular activities was not associated with parental media regulation. In contrast, parental screen time was related to more frequent co-use and less frequent use of restrictive and technical mediation.

CONCLUSION

Parental regulation of child media use is influenced by parental attitudes and a perceived need for mediation (e.g., in younger children or children owning internet-enabled devices) rather than child behavior.

Mental health in children and adolescents with overweight or obesity

BACKGROUND

Overweight and obesity represent huge concerns for children's physical and mental well-being. This study examined the relationship between body mass index (BMI) and health-related quality of life (HRQoL), somatoform complaints, and behavioral problems in children and adolescents. Additionally, the influence of sex, age, and socioeconomic status (SES) on these associations was considered.

METHODS

In total, we studied 2350 participants between the ages of 4 and 18 years (1213 4- to 10-years-old (child sample) and 1137 11-to 18-year-olds (adolescent sample)). To assess HRQoL, somatoform complaints, and behavioral difficulties, we applied the KIDSCREEN-27, a short form of the Giessen Complaints Questionnaire, and the Strengths and Difficulties Questionnaire (SDQ). The BMI was transformed to BMI standard deviation scores (BMI-SDS), according to German gender- and age-specific reference data. Associations were investigated using linear regression analyses. Each association was checked for interaction with sex, age, and SES.

RESULTS

Regarding HRQoL, we found worsening scores in physical well-being and psychological well-being with increasing BMI-SDS. Somatoform complaints were not significantly associated with BMI-SDS. Conduct problems, peer relationship problems, and emotional problems (the latter only in the adolescent sample) were positively associated with BMI-SDS. While we did not observe any significant interactions with sex, we found some significant interactions with age and/or SES.

CONCLUSION

Our findings highlight the importance of mental difficulties in children and adolescents with higher BMI and, consequently, underline the relevance of including psychological interventions in the treatment of overweight or obesity.

Associations between Stressful Life Events and Increased Physical and Psychological Health Risks in Adolescents: A Longitudinal Study

Stressful life events (SLEs) are understood as risk factors for mental and physical health problems, particularly in the vulnerable period of adolescence. Using a longitudinal approach, this study investigated associations between SLE and several negative health outcomes in adolescents. Moderating effects of sociodemographic factors were considered. We analyzed the data of a healthy adolescent sample from the LIFE Child study in Leipzig, Germany (n = 2024, aged 10-18 years). SLEs were measured by a questionnaire, addressing SLEs in the family and the social environment domain. Health-related quality of life (HrQoL), behavioral difficulties and BMI were compared before and after an SLE had occurred. Moderator effects of socioeconomic status (SES), age, and sex were investigated using linear regression models. All considered health parameters had, on average, deteriorated after the occurrence of an SLE in the social environment. Differences in HrQoL before and after an SLE were significantly stronger in girls. Higher SES functioned as a slight protective factor against decreased well-being after an SLE. The findings suggest that SLEs function as risk factors for mental and physical health disadvantages in adolescents. Prevention programs should seek to support adolescents in all age and SES groups affected by SLEs, with a specific focus on girls.

The relationship between myopia and near work, time outdoors and socioeconomic status in children and adolescents

Background

To investigate environmental and social risk factors for myopia in children and adolescents in Germany.

Methods

1437 children aged between 3 and 18 inclusive were examined as part of the LIFE Child study based in Leipzig, Germany. Information about leisure time activities and social status was ascertained by parents and children in a questionnaire. Refractive status was attained by measuring noncycloplegic autorefraction. Myopia was defined as spherical equivalent (SE) ≤ − 0.75 D. Risk factors were identified using multiple logistic regression analysis.

Results

In multiple logistic regression analysis, myopia was significantly associated with less frequent outdoor activity (“once a week” vs. “twice a week or more”: odds ratio (OR) 4.35, 95% confidence interval (CI) 1.89–9.98, p<0.01) and longer near work sessions (1–2 h vs. < 1 h: OR 1.83, CI 1.10–3.04, p=0.02; > 3 h vs. < 1 h: OR 3.71, CI 1.43–9.61, p<0.01) after adjustment for age, sex and socioeconomic status (SES). Duration of outdoor activity, near work frequency and SES showed no significant association with myopia (p > 0.05). Children with a lower SES were involved in longer periods of outdoor and near work activities but on fewer occasions over the course of the week, although this connection was not significant.

Conclusion

Myopia is associated with environmental factors. The present findings suggest that daily exposure to sunlight and a restriction of long-duration near work activities might protect against pathological eye growth. Prevention strategies should be implemented for children at all ages.

Associations between sociodemographic and behavioural parameters and child development depending on age and sex: a cross-sectional analysis

OBJECTIVES

To explore environmental and individual factors that are associated with child development and to investigate whether the strength of these associations differs according to the age of the children.

DESIGN

Cross-sectional study.

SETTING

This study was part of the LIFE Child study, a large cohort study conducted in Leipzig, Germany.

PARTICIPANTS

778 children aged between 0.5 and 6 years (48.6% girls, mean age=2.67 years).

OUTCOME MEASURES

The outcomes were cognitive development, language development, body and hand motor skills, social-emotional development, and tracing skills, measured with a standardised development test. We analysed the associations between development and gestational age, socioeconomic status (SES), sex, behavioural difficulties, siblings, sleep duration, breastfeeding duration and overweight/obesity. We also tested for interactions between these variables and child age or sex.

RESULTS

Higher gestational age (b ranging between 0.12 and 0.26) and higher SES (b ranging between 0.08 and 0.21) were associated with better outcomes in almost all developmental domains (all p<0.019). Children with older siblings had improved body and hand motor skills compared with children without older siblings (both b=0.55, all p<0.029). Boys had poorer scores than girls in body and hand motor skills and tracing (b=-0.45, -0.68 and -1.5, all p<0.019). Children with behavioural difficulties had significantly poorer outcomes in most developmental domains. Some of the associations with SES and sex were stronger in older than in younger children. Associations between gestational age and motor development were weaker in older children. We did not find significant associations between child development and sleep duration, breastfeeding duration or overweight/obesity.

CONCLUSION

Some factors had a protective, others an adverse effect on development of children under 6 years of age. The effect of SES and sex increased, while the effect of gestational age decreased with age.

TRIAL REGISTRATION NUMBER

NCT02550236.

Association between hair cortisol concentration and behavioral difficulties in children and adolescents

This study aimed to assess associations between behavioral difficulties and an objectively measurable indicator for long-term stress (hair cortisol) in children and adolescents. We expected increased hair cortisol levels in participants with more externalizing (conduct problems, hyperactivity/inattention) or internalizing (peer relationship problems, emotional problems) behavioral difficulties. Behavioral difficulties were assessed using the parent version of the Strengths and Difficulties Questionnaire (SDQ). Hair cortisol concentration (HCC), measured via liquid chromatography mass spectrometry (LC-MS3), was used as stress marker. A 1 cm strand of hair was cut off from the occipital or parietal cranium closest to the scalp. The study sample comprised 1321 children and adolescents aged between 3 and 17 years participating in the LIFE Child cohort study (Leipzig, Germany). To assess associations, we applied multiple linear regression analyses. Only a few associations met expectations, others contradicted our hypotheses. No association reached statistical significance. The present findings may suggest that behavioral difficulties gathered by SDQ are not associated with stress measured through HCC.

Having siblings promotes a more healthy weight status—Whereas only children are at greater risk for higher BMI in later childhood

Background

Birth order and having at least one sibling are known to be associated with an increased risk for development of overweight. However, there are no studies assessing pre- and postnatal factors for developing overweight within families. Therefore, the present study aimed to analyse the association of the mother’s weight gain during pregnancy, prepregnancy BMI, mother’s age at birth, breastfeeding, age gap between siblings, and physical activity together with sibling-related characteristics on the development of overweight in children and adolescents.

Methods

Data were obtained from the longitudinal LIFE Child cohort. The study sample included n = 1932 children, stratified into first-born (n = 578), second-born (n = 608), third-or-later-born single-born siblings (n = 162), only children (n = 526), and twin children (n = 58). Children with chronic or syndromic diseases, born prematurely or from mothers with gestational diabetes were excluded. Data were adjusted for multiple children per family using mixed models. Pregnancy weight gain, prepregnancy BMI and mother’s age were considered prenatal co-variates. Postnatal factors included the duration of breastfeeding and the children’s physical activity level.

Results

Particularly until the onset of puberty, the BMI-SDS differed between single-born siblings, only children and twins, and increased with birth order. Compared to children with siblings, only children exhibited a strong increase in BMI-SDS starting at age nine. A higher age gap between siblings was associated with a higher BMI-SDS in second- and third-or-later-born children. Single-born siblings had the highest rate and duration of breastfeeding. Physical activity was highest in twins and third-or-later-born children and lowest in only children. In a multivariate model, being an only child showed a highly significant association with BMI-SDS.

Conclusion

The present study demonstrated that siblings had a lower BMI-SDS than only children did. For single-born siblings, the association between birth order and increased BMI-SDS seemed to persist only up to 11 years of age.

Association of sleep quality, media use and book reading with behavioral problems in early childhood. The Ulm SPATZ Health Study

Study Objectives

The objective of the study was to investigate the association of sleep quality, media use and book reading on internalizing, externalizing and prosocial behavior in early childhood.

Methods

In this cross-sectional study, we investigated a data set consisting of three consecutive yearly waves of the prospective Ulm SPATZ Health Study, conducted in southern Germany with 565, 496, and 421 children of 4-6 years of age, respectively.Standardized effects of the overall score and subscales of the Children's Sleep Habits Questionnaire, parent-reported child media use and book reading as well as their interaction term on the total score of the Strengths and Difficulties Questionnaire along with its externalizing, internalizing and prosocial subscales were estimated by multivariate adjusted random intercept mixed models.

Results

Overall sleep quality was associated more with internalizing than externalizing behavior; parasomnias associated with both behaviors. Night waking and sleep anxiety associated only with internalizing behavior. High levels of media use were associated with less internalizing behavior. More book reading resulted in less externalizing and internalizing behavior but more prosocial behavior. Finally, book reading and media use do not interact to determine child's behavior.

Conclusions

The current work supports a strategy of monitoring sleep quality, reducing media use and promoting book reading in order to avoid behavioral problems in early childhood.

Associations between problematic smartphone use and behavioural difficulties, quality of life, and school performance among children and adolescents

BACKGROUND

European studies on determinants and factors associated with problematic smartphone use (PSU) in children and adolescents are still sparse. This study reports the current amount of PSU symptoms and the presence of (clinically relevant) PSU in German children and adolescents. We also investigated associations between socio-demographic factors, different smartphone usage patterns, and daily smartphone usage time and the amount of PSU symptoms in this group. In addition, associations of PSU symptoms and high smartphone usage times (> 2 h/day) with behavioural problems, quality of life (QoL), and school performance were investigated.

METHODS

Within the framework of the LIFE Child study, 564 children and adolescents aged 10-18 years provided information on PSU symptoms (using the Smartphone Addiction Proneness Scale), daily smartphone usage time, smartphone activities, behavioural strengths and difficulties (using the Strengths and Difficulties Questionnaire), QoL (using the KIDSCREEN-27), and school performance. Multiple regression analyses were applied to assess associations.

RESULTS

In the present sample, PSU was present in 13 children (2.3%). Older age, female gender, high daily smartphone usage time of > 2 h, and intensive smartphone use for social networking, gaming, or watching video clips were significantly associated with more PSU symptoms. Children and adolescents reporting more PSU symptoms also showed lower QoL, more behavioural difficulties, and poorer school performance, independently of age, gender, socio-economic status, and daily smartphone usage time. In contrast, daily smartphone usage time per se showed only weak or non-significant associations with these aspects of health and behaviour.

CONCLUSION

Intensive smartphone use for entertainment may increase the risk of developing PSU symptoms. Furthermore, the results indicate that PSU symptoms (more than long smartphone usage times per se) are associated with more behavioural difficulties and poorer QoL.

Association of Oral Health Conditions in Adolescents with Social Factors and Obesity

This study aimed to investigate associations between psychosocial factors, obesity, and oral health in a study population of 10- to 18-year-old adolescents who participated in the LIFE Child study. Psychosocial information (socioeconomic status (SES) based on parents’ education, occupation and household income, Strengths and Difficulties Questionnaire (SDQ), health-related quality of life) and physical activity behavior were obtained. Nutritional status was classified based on age- and sex-adjusted body mass index into underweight, overweight, normal weight and obese. Clinical dental examinations were performed and scored with respect to caries experience (CE), oral hygiene (OH), and periodontal status (periodontal health score: PERIO-S). Age-adjusted regression analysis under the assumption of a double Poisson distribution was performed with and without adjusting for SES (α = 5%). A total of 1158 study participants (590 girls, 568 boys; mean age 13.2 ± 2.3 years) were included (17.2% were classified as obese). CE was 20% higher for moderate and 60% higher for low SES compared to high SES (p < 0.05). PERIO-S was 10% higher for moderate and 30% higher for low compared to high SES (p < 0.05). Poor OH was associated with higher CE (Ratio R = 2.3, p < 0.0001) and PERIO-S (R = 3.1, p < 0.0001). Physical activity in a sports club was associated with lower CE-S and PERIO-S (R = 0.85, p < 0.001). Obesity was associated with increased CE (R = 1.3, p < 0.001) compared to normal weight. For low but not high SES, more reported difficulties were associated with higher CE. In conclusion, low SES, poor OH, and obesity are associated with unfavorable oral health conditions, whereas physical activity and high SES are potentially protective.

HbA1c percentiles and the association between BMI, age, gender, puberty, and HbA1c levels in healthy German children and adolescents

OBJECTIVE

The measurement of glycated hemoglobin (HbA1c) represents one way to detect type 1 and 2 diabetes in children at an early stage. However, to date, variations in HbA1c levels are not fully understood, even in healthy children. With this in mind, the present study aimed to establish HbA1c reference values in healthy children and to investigate the influence of various independent variables.

STUDY DESIGN AND METHODS

Two thousand four hundred fifty-five healthy children and adolescents aged between 0.5 and 18 years participated in the population-based cohort study LIFE Child, Germany. Age- and gender-dependent percentiles were estimated, enabling HbA1c values to be converted into standard deviation scores (SDS). Logistic regression models were applied to assess associations between HbA1c-SDS (as outcome) and age, gender, BMI, birth weight, physical activity, pubertal status, and socioeconomic status (SES; as explanatory variables).

RESULTS

The mean HbA1c value was 31.79 mmol/mol or 5.06% (SD = 3.3 mmol/mol, SD = 0.3%). Positive associations with HbA1c values were identified for age (b = 0.09, p < 0.001), gender (b = 0.25, p = 0.007), and BMI-SDS (b = 0.06, p < 0.001). In addition, obesity was related to higher HbA1c values (b = 0.29, p < 0.001). Compared to prepuberty, the pubertal and postpubertal stages were associated with higher HbA1c levels. Furthermore, higher SES was associated with higher HbA1c-SDS (b = 0.01, p = 0.04).

CONCLUSION

The present study established HbA1c reference values based on a large sample of healthy German children and adolescents. Age, gender, SES, pubertal stage, and BMI were found to be associated with higher HbA1c levels.

Wellbeing, coping with homeschooling, and leisure behavior at different COVID‐19‐related lockdowns: A longitudinal study in 9‐ to 16‐year‐old German children

Background

School closures are an effective measure against the spread of Covid‐19. However, they pose a major challenge to children, especially to those from socially disadvantaged families. The present study compared the wellbeing, coping with homeschooling, and leisure behavior of children and adolescents at two different periods of school closures in Germany. Wellbeing was also compared with wellbeing before the pandemic.

Methods

Within the framework of the cohort study LIFE Child, 152 9‐ to 16‐year‐old children completed online surveys on wellbeing (KIDSCREEN‐27 scales on physical wellbeing, psychological wellbeing, and peer and social support), coping with homeschooling (concentration, motivation, fun, mastering of schoolwork, fear of bad marks), and leisure behavior (TV time, computer gaming time, indoor physical activity) during two COVID‐19‐related lockdowns in March 2020 (t1) and in January 2021 (t2). Data from both time points were compared using mixed‐effect models. Wellbeing was additionally compared with the wellbeing in 2019, before COVID‐19 (t0). We also assessed the effects of the socio‐economic status (SES) on all outcomes and changes between time points.

Results

All considered wellbeing scores declined significantly between t0 and t1. Physical wellbeing decreased further between t1 and t2, while social support increased. Coping with homeschooling degraded significantly between t1 and t2, while leisure behavior did not change significantly. Lower SES was associated with lower physical wellbeing, poorer coping with homeschooling, longer computer gaming times, and a stronger decrease of concentration on schoolwork from t1 to t2.

Conclusion

Repeated school closures have a negative effect on already compromised physical wellbeing and coping with homeschooling, especially in children from lower social strata.

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.

Reference centiles based on year-to-year changes for a longitudinal evaluation of motor performance in children and adolescents

Objectives

The aim was to evaluate the longitudinal course of motor skills development in children with a view to improve the understanding of intra-individual variance. Previous publications have been based on cross-sectional data or analyzed longitudinal studies in a cross-sectional manner.

Design

Longitudinal. Year-to-year change.

Methods

The present study is based on motor function data collected in the LIFE Child study (Germany). The participants (6 to 17 years) completed parts of the motor tests according to the standard of the German Motor Performance Test 6–18 (DMT). For a total of 1653 participants, 4616 motor tests with an annual interval in the period 2011 to 2019 were included in the evaluation.

Results

We were able to produce gender and age-specific change centiles for the test items standing long jump, jumping sideways, push-ups, stand and reach and balancing walking backwards. Each set of centiles revealed a range of variability in motor development in children and adolescents, with distinct progressive patterns in the different test items and different genders. The supplied tables offer an indication of expected year-to-year change for each test item depending on age and gender. Depending on the test item and the mean age, a deterioration in test results after a one-year interval was observed, despite cross-sectional centiles showing an upward trend.

Conclusion

We present a user-friendly tool as a way to assess individual dynamic changes in motor development of children and adolescents. In combination with the well-known cross-sectional centiles as baseline, this can be helpful for the scientific evaluation of motor skills tests and can also be used in school settings.

Age- and weight group-specific weight gain patterns in children and adolescents during the 15 years before and during the COVID-19 pandemic

BACKGROUND/OBJECTIVES

There is a concern that measures aiming to limit a further spread of COVID-19, e.g., school closures and social distancing, cause an aggravation of the childhood obesity epidemic. Therefore, we compared BMI trends during the 15 years before and during the COVID-19 pandemic.

SUBJECTS/METHODS

To assess the change in weight dynamics during the first months of COVID-19, we compared the trends of 3-month change in BMI-SDS (ΔBMI-SDS) and the proportions of children showing a high positive (HPC) or high negative (HNC) weight change between 2005 and 2019 and the respective changes from 2019 (pre-pandemic) to 2020 (after the onset of anti-pandemic measures) in more than 150,000 children (9689 during the pandemic period). The period of 3 months corresponds approximately to the first lockdown period in Germany.

RESULTS

During the COVID-19 pandemic, we found a substantial weight gain across all weight and age groups, reflected by an increase in the 3-month change in BMI-SDS (β = 0.05, p < 0.001), an increase in the proportion of children showing HPC (OR = 1.4, p < 0.001), and a decrease in the proportion of children showing HNC (OR = 0.7, p < 0.001). Besides, we found the same trends since 2005 on a low but stable level with a yearly increase of ΔBMI-SDS by β = 0.001 (p < 0.001), the odds of HPC increased by ORhigh_pos = 1.01 (p < 0.001), and the odds of HNC decreased by ORhigh_neg = 0.99 (p < 0.001). These rather small effects accumulated to β = 0.02, ORhigh_pos = 1.14, and ORhigh_pos = 0.85 over the whole period 2005-2019. Alarmingly, both the long-term and the short-term effects were most pronounced in the obese subgroup.

CONCLUSIONS

There are positive dynamics in different measures of weight change, indicating a positive trend in weight gain patterns, especially within the group of children with obesity. These dynamics are likely to be escalated by COVID-19-related measures. Thus, they may lead to a significant further aggravation of the childhood obesity pandemic.

Effect of physical activity and BMI SDS on bone metabolism in children and adolescents

OBJECTIVE

Children with obesity are known to have reduced bone density and are at a higher risk for fractures. This may be caused by decreased physical activity or a metabolic phenomenon. In this study, we evaluated associations of physical activity with bone metabolism in children and adolescents with and without obesity.

METHODS

Results from 574 visits of 397 subjects, 191 girls and 206 boys aged five to 18 years (mean: 11.7 ± 2.8) representing 180 children with (mean BMI SDS 2.5 ± 0.4) and 217 without obesity (mean BMI SDS 0.2 ± 1.0) from the LIFE Child study, a population-based cohort of children/adolescents with normal weight and with obesity were analyzed for the impact of their daily physical activity (MET/day, SenseWear Accelerometer) on serum SDS levels for bone formation (alkaline phosphatase, osteocalcin, procollagen type I N propeptide [P1NP]), bone resorption (beta-crosslaps), and calcium homeostasis (parathormone, OH-25-vitamin D) by a linear regression model adjusted for gender- and age-based differences.

RESULTS

For male subjects, BMI SDS significantly influenced the association of physical activity to PTH, vitamin D, and beta-crosslaps SDS levels. A higher physical activity was accompanied by increased PTH but decreased vitamin D SDS levels in children with normal weight. In males with obesity, all levels remained unaltered. In females, BMI SDS significantly impacted the association of physical activity to PTH, vitamin D, P1NP, beta-crosslaps, and osteocalcin SDS levels. In females with obesity, higher physical activity was related to higher SDS levels of vitamin D, P1NP, and beta-crosslaps. In contrast, in normal weight females, only PTH SDS was higher.

CONCLUSIONS

The effect of daily physical activity on bone metabolic markers and calciotropic hormones depends significantly on gender and BMI SDS. However, higher levels of physical activity were associated with increased bone turnover for female subjects with obesity only. Thus, motivating especially girls with obesity to be physically active may help improve their bone health.

Purchasing Behavior, Setting, Pricing, Family: Determinants of School Lunch Participation

Despite growing school lunch availability in Germany, its utilization is still low, and students resort to unhealthy alternatives. We investigated predictors of school lunch participation and reasons for nonparticipation in 1215 schoolchildren. Children reported meal habits, parents provided family-related information (like socioeconomic status), and anthropometry was conducted on-site in schools. Associations between school lunch participation and family-related predictors were estimated using logistic regression controlling for age and gender if necessary. School was added as a random effect. School lunch participation was primarily associated with family factors. While having breakfast on schooldays was positively associated with school lunch participation (ORadj = 2.20, p = 0.002), lower secondary schools (ORadj = 0.52, p < 0.001) and low SES (ORadj = 0.25, p < 0.001) were negatively associated. The main reasons for nonparticipation were school- and lunch-related factors (taste, time constraints, pricing). Parents reported pricing as crucial a reason as an unpleasant taste for nonparticipation. Nonparticipants bought sandwiches and energy drinks significantly more often on school days, whereas participants were less often affected by overweight (OR = 0.66, p = 0.043). Our data stress school- and lunch-related factors as an important opportunity to foster school lunch utilization.

New reference intervals for endocrinological biomarkers in pediatric patients: what can we learn from the LIFE child study?

Objectives

We established reference intervals for serum concentrations of hormones from healthy pediatric subjects and investigated their associations with gender, body mass index (BMI), puberty and oral contraceptives (oC).

Methods

We calculated reference intervals for the thyroid parameters thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), and calcitonin (Ct); the bone markers osteocalcin, procolagen type 1 N-propeptide, and carboxy-terminal cross-linking telopeptide of type 1 collagen; the calciotropic hormones 25-hydroxyvitamin D (25(OH)D) and parathyroid hormone and the steroids cortisol, progesterone, 17-hydroxyprogesterone, androstenedione, testosterone, estradiol, dehydroepiandrosterone sulfate and aldosterone. Up to 10,002 blood serum samples from 3,229 healthy children and adolescents (age interval: 3 months to 20 years) were measured. To investigate the associations between the hormone levels with age, sex, weight status and the role of puberty-based changes, the measurement and BMI values were transformed into standard deviation scores.

Results

Most of the hormones depended on age- and gender. Puberty was linked to a, in part, temporary decrease in TSH, FT3 (for females), FT4, Ct, cortisol (for girls) and aldosterone (for boys) and peak in the bone marker and calciotropic hormones (excluding 25(OH)D) and nearly all remaining steroids. BMI had effects on the thyroid, bone, and calciotropic parameters, whereas oC led to increased cortisol, suppressed progesterone and estradiol values.

Conclusions

Age- and gender-specific reference intervals are essential for the interpretation of pediatric patients’ hormone measurements. Influencing factors as puberty, BMI, or oC should be taken into consideration for diagnosis and treatment monitoring.

Changes in diet from pregnancy to one year after birth: a longitudinal study

Background

Pregnancy and the first year after giving birth are marked by physiological and psychological changes. While it is well known that energy requirements change during this time, the question of how a woman’s diet actually changes from pregnancy until 1 year postpartum has been left virtually unexplored. The present study employs a longitudinal design to investigate these changes.

Methods

Data were collected within the framework of the LIFE Child study (Leipzig, Germany). The diet composition and culture of eating of 110 women were assessed at 3 time points: in the 24th week of pregnancy, 3 months after giving birth (breastfeeding period), and 12 months after giving birth (after weaning). We assessed differences in nutritional health (Nutritional Health Score, NHS) and the consumption of different food items at each of these time points. We also investigated associations between nutritional health and age, socio-economic status (SES), BMI before pregnancy, and previous births at all three time points.

Results

The analyses revealed high correlations in the NHS values between the three time points (rho_t0/t1 = .55, rho_t0/t2 = .60). On average, nutritional health was lower in the breastfeeding period than during pregnancy. In more detail, women reported less healthy levels of treats and white bread consumption and a higher frequency of snacking in the breastfeeding period than during pregnancy. In contrast, overall nutritional health did not differ significantly between pregnancy and the time after weaning. Increased age was associated with a healthier diet during pregnancy, and a high SES was associated with healthier diet after weaning. Furthermore, the increase in nutritional health from the breastfeeding period to the time after weaning was significantly stronger in women with a higher BMI. We observed no significant associations between dietary nutritional health and previous births.

Conclusions

The present findings suggest that higher energy requirements in the breastfeeding period are met by consuming high-calorie and unhealthy food products rather than healthy and nutrient-rich food. Young mothers should be supported in taking care of their own nutritional health during the challenging time of breastfeeding and caring for a newborn child.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04038-3.

Associations of prenatal exposure to phthalates and one phthalate substitute with anthropometric measures in early life: Results from the German LIFE Child cohort study

Exposure to phthalates is widespread and especially early life stages represent a critical window of exposure. In the present study, we investigated the effect of prenatal exposure to phthalates on birth outcomes and weight development in early life. In 130 mother-child pairs, we estimated the association of concentrations of 13 phthalates in spot-urine samples collected during pregnancy and birth outcomes and weight gain in the first two years of life using robust linear regression. High molecular weight phthalates were inversely associated with birth weight in girls but not in boys. Thus, prenatal exposure to phthalates may affect birth weight in a sex-specific manner.

Atopic diseases in children and adolescents are associated with behavioural difficulties

Background

Atopic diseases and behavioural difficulties in children have both been on the rise in recent decades. This study seeks to assess associations between atopic diseases and behavioural difficulties, examining the differences considering child age and how behavioural difficulties were reported (via self-report or parent-report).

Methods

Data on behavioural difficulties, assessed through the Strengths and Difficulties Questionnaire (SDQ), and on atopic diseases, assessed through the participant’s medical history, were available for 2701 study participants aged 3 to 18 years. Associations between atopic diseases and behavioural difficulties were evaluated using linear regression analyses. We split the study sample into two groups. I: 3-to 10-year-olds/parent-reported SDQ (n = 1764), II: 11- to 18-year-olds/parent-reported SDQ (n = 937) and self-reported SDQ (n = 915). All analyses were adjusted for age, gender, and socioeconomic status.

Results

In younger children, atopic dermatitis was strongly associated with higher total difficulties scores, more emotional problems and conduct problems, and more symptoms of hyperactivity/inattention. Parents reported higher total difficulties scores, more emotional problems, and more peer-relationship problems for adolescents with bronchial asthma and other allergies, whereas the adolescents themselves reported more peer relationship problems.

Conclusion

In younger children, atopic dermatitis is associated with internalizing and externalizing problems. In adolescents, bronchial asthma and other allergies are associated with a greater level of internalizing problems only. The findings further suggest that parents of adolescents are more likely to perceive associations between atopic diseases and behavioural difficulties than the adolescents themselves.

And yet Again: Having Breakfast Is Positively Associated with Lower BMI and Healthier General Eating Behavior in Schoolchildren

Given the high prevalence of childhood overweight, school-based programs aiming at nutritional behavior may be a good starting point for community-based interventions. Therefore, we investigated associations between school-related meal patterns and weight status in 1215 schoolchildren. Anthropometry was performed on-site in schools. Children reported their meal habits, and parents provided family-related information via questionnaires. Associations between nutritional behavior and weight status were estimated using hierarchical linear and logistic regression. Analyses were adjusted for age, socio-economic status, school type, migration background, and parental weight status. Having breakfast was associated with a lower BMI-SDS (βadj = -0.51, p = 0.004) and a lower risk of being overweight (ORadj = 0.30, p = 0.009), while having two breakfasts resulting in stronger associations (BMI-SDS: βadj = -0.66, p < 0.001; risk of overweight: ORadj = 0.22, p = 0.001). Likewise, children who regularly skipped breakfast on school days showed stronger associations (BMI-SDS: β = 0.49, p < 0.001; risk of overweight: OR = 3.29, p < 0.001) than children who skipped breakfast only occasionally (BMI-SDS: β = 0.43, p < 0.001; risk of overweight: OR = 2.72, p = 0.032). The associations persisted after controlling for parental SES and weight status. Therefore, our data confirm the school setting as a suitable starting point for community-based interventions and may underline the necessity of national programs providing free breakfast and lunch to children.

COVID-19 pandemic and families' utilization of well-child clinics and pediatric practices attendance in Germany

Objective

The COVID-19 pandemic and the measures implemented to stop the pandemic had a broad impact on our daily lives. Besides work and social life, health care is affected on many levels. In particular, there is concern that attendance in health care programs will drop or hospital admissions will be delayed due to COVID-19-related anxieties, especially in children. Therefore, we compared the number of weekly visits to 78 German pediatric institutions between 2019 and 2020.

Results

We found no significant differences during the first 10 weeks of the year. However, and importantly, from April, the weekly number of visits was more than 35% lower in 2020 than in 2019 (p = 0.005). In conclusion, the COVID-19 pandemic seems to relate to families´ utilization of outpatient well-child clinics and pediatric practice attendance in Germany.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13104-021-05562-3.

Birth weight increases with birth order despite decreasing maternal pregnancy weight gain

AIM

We investigated whether birth order is an influencing factor for birth weight independent from maternal factors.

METHODS

Data were obtained from the longitudinal cohort study LIFE Child and included 1864 children, of which 526 were only children. The 1338 siblings were ranked into first-borns (n = 570), second-borns (n = 606) and third-or-later-borns (n = 162). Children born prematurely, suffering from chronic or syndromic diseases, were excluded. We performed intra-family comparisons to reduce bias and assessed the impact of perinatal parameters, such as birth order on birth weight, using mixed models.

RESULTS

Birth weight increased with birth order. In univariate analyses, birth order had a significant effect on birth weight-SDS with second-borns having 0.29 SDS (app. 130 g) and third-borns 0.40 SDS (app. 180 g) higher values than first-borns (P < .001). Maternal pregnancy weight gain was associated with higher birth weight-SDS (P < .01) in univariate analysis, though maternal pregnancy weight gain was lower for higher birth orders. Multivariate analyses revealed that being a second or third-or-later-born child had a stronger impact on birth weight than all maternal factors.

CONCLUSION

Birth order must be considered a potential risk factor for higher birth weight. Maternal pregnancy weight gain is not the driving factor for higher birth weight in siblings.

Well-being and COVID-19-related worries of German children and adolescents: A longitudinal study from pre-COVID to the end of lockdown in Spring 2020

Background

There is concern that pandemic measures put a strain on the health and well‐being of children. We investigated the effects of the COVID‐19 pandemic, the lockdown, and social distancing on the well‐being, media use, and emotions of children and adolescents between 9 and 18 years.

Methods

We used linear and proportional odds logistic regression correcting for age, sex, and socioeconomic status (SES) and to compare media use, peers/social support, physical, and psychological well‐being between 2019 (pre‐COVID baseline) and two time points shortly after the start of the lockdown (last week of March and April 2020, respectively) in 391 9–19‐year‐old healthy children and adolescents of the LIFE Child cohort. COVID‐19‐related feelings and their relationship to age, sex, and SES were assessed at two time points during lockdown.

Results

We found significantly lower scores in physical and psychological well‐being during lockdown compared to baseline. The effect was significantly stronger in children with medium/low SES. Perceived social support scores were also significantly lower during the lockdown. The percentage of children who had no contact with their peers (in‐person or online) increased from 3% pre‐COVID to 14% and 13% in April and March 2020, respectively. About 80% of the children missed in‐person contacts with friends. Most of the children worried more about the health of their families than their own. Sixty percent worried about the international situation at least moderately, whereas only 20% were afraid of COVID‐19 itself. The percentage of children who believed it would never be as before COVID‐19 rose from 7.4% at the beginning lockdown end of March to 16.2% a month later. In contrast, all other COVID‐19‐related worries, showed a (nonsignificant) decline during the same period.

Conclusion

Our study supports the notion that pandemic measures have to be balanced against adverse public health effects. Especially vulnerable groups have to be protected.

Loss of childcare and classroom teaching during the Covid-19-related lockdown in spring 2020: A longitudinal study on consequences on leisure behavior and schoolwork at home

Aim

In spring 2020, the first Covid-19-related lockdown included the closing of kindergartens and schools. Home schooling, the lack of social contacts with peers and the care of the children at home posed an enormous challenge for many families.

Methods

The present study investigated the leisure behavior of 285 one- to 10-year-old German children at two time points (t1 and t2) during the Covid-19-related lockdown in spring 2020. In the subsample of primary school children (n = 102), we also explored children’s attitudes towards schoolwork at home. Analyses focused on the change of behavior from t1 to t2, on differences in these changes depending on socio-economic status (SES), and on associations of behavior with SES, the number of children at home, and the frequency of receiving learning materials from school.

Results

While the frequency of playing outside increased significantly from t1 to t2, the frequency of handicrafts, playing board games, indoor sports, and motivation to do schoolwork decreased. The observed changes between t1 and t2 did not differ depending on SES. However, a lower SES was associated with higher media use, less outdoor activity, and (though only marginally significant) a reduced time doing schoolwork and a reduced ability to concentrate on schoolwork at t1. In households with more children, children played outside more often, but were read to less frequently and (though only marginally significant) watched movies and series less frequently. Children receiving learning materials from school on a regular basis spent significantly more time doing schoolwork at home than children receiving materials only irregularly.

Conclusions

A continuing loss of childcare in day-care facilities and schools entails the danger of declining education in the form of (inter)active indoor activities and schoolwork.

Sleep-related difficulties in healthy children and adolescents

BACKGROUND

As sleep-related difficulties are a growing public health concern, it is important to gain an overview of the specific difficulty areas of the most vulnerable individuals: children. The current descriptive study presents the prevalence of sleep-related difficulties in two large samples of healthy children and adolescents and outlines the effects of age, gender, and socioeconomic status (SES) on various sleep-related difficulties.

METHODS

Participants were 855 4-9 year-old children (child sample) and 1,047 10-17 year-old adolescents (adolescent sample) participating 2011-2015 in the LIFE Child study, a population-based cohort study in Germany. Parents of the child participants completed the Children's Sleep Habits Questionnaire (CSHQ), whereas adolescents self-administered the Sleep Self Report (SSR). Familial SES was determined by a composite score considering parental education, occupational status, and income. Multiple regression analyses were carried out to address the research question.

RESULTS

Among 4-9 year-old children, the mean bedtime was reported to be 8 p.m., the mean wake-up time 7 a.m., and sleep duration decreased by 14 min/year of age. 22.6 % of the children and 20.0 % of the adolescents showed problematic amounts of sleep-related difficulties. In the child sample, bedtime resistance, sleep onset delay, sleep-related anxiety, night waking, and parasomnia were more frequent in younger than older children. In the adolescent sample, difficulties at bedtime were more frequent among the younger adolescents, whereas daytime sleepiness was more prominent in the older than the younger adolescents. Considering gender differences, sleep-related difficulties were more frequent among boys in the child sample and among girls in the adolescent sample. Lower SES was associated with increased sleep-related difficulties in the adolescent, but not the child sample.

CONCLUSIONS

The present results report sleep-related difficulties throughout both childhood and adolescence. Gender differences can already be observed in early childhood, while effects of SES emerge only later in adolescence. The awareness for this circumstance is of great importance for pediatric clinicians who ought to early identify sleep-related difficulties in particularly vulnerable individuals.

Establishing Normative Data on Singing Voice Parameters of Children and Adolescents with Average Singing Activity Using the Voice Range Profile

PURPOSE

The purpose of this study was to establish and characterize age- and gender-specific normative data of the singing voice using the voice range profile for clinical diagnostics. Furthermore, associations between the singing voice and the socioeconomic status were examined.

METHODS

Singing voice profiles of 1,578 mostly untrained children aged between 7.0 and 16.11 years were analyzed. Participants had to reproduce sung tones at defined pitches, resulting in maximum and minimum fundamental frequency and sound pressure level (SPL). In addition, maximum phonation time (MPT) was measured. Percentile curves of frequency, SPL and MPT were estimated. To examine the associations of socioeconomic status, multivariate analyses adjusted for age and sex were performed.

RESULTS

In boys, the mean of the highest frequency was 750.9 Hz and lowered to 397.1 Hz with increasing age. Similarly, the minimum frequency was 194.4 Hz and lowered to 91.9 Hz. In girls, the mean maximum frequency decreased from 754.9 to 725.3 Hz. The mean minimum frequency lowered from 202.4 to 175.0 Hz. For both sexes, the mean frequency range ∆f showed a constant range of roughly 24 semitones. The MPT increased with age, for boys and girls. There was neither an effect of age nor sex on SPLmin or SPLmax, ranging between 52.6 and 54.1 dBA and between 86.5 and 82.8 dBA, respectively. Socioeconomic status was not associated with the above-mentioned variables.

CONCLUSION

To our knowledge, this study is the first to present large normative data on the singing voice in childhood and adolescence based on a high number of measurements. In addition, we provide percentile curves for practical application in clinic and vocal pedagogy which may be applied to distinguish between normal and pathological singing voice.

The Associations Between Media Use, Midpoint of Sleep, and Sleep Quality in German Preschoolers: A Mediation Analysis Based on the Ulm SPATZ Health Study

INTRODUCTION

The relation of electronic media use with sleep quality among preschoolers is a matter of ongoing debate. Longitudinal data are scarce and do not account for sleeping schedules.

METHODS

We used the German Children's Sleep Habits Questionnaire to measure parent-reported child's sleep quality; its score is computed by the sum of 34 items defined by a 1-3 level Likert scale (score ranging 34-102), with higher values representing lower sleep quality. A causal mediation analysis of these relations using data from the Ulm SPATZ Health Study in Germany was conducted. Repeated data on electronic media use, book reading, sleep quality, sleep duration, and midpoint of sleep were prospectively collected yearly from ages 4 to 6 years (n=563) during parent's working days and free days.

RESULTS

We observed negative correlations of sleep quality with sleep duration and midpoint of sleep at ages 4-5 (R=-0.21 to -0.10), which attenuated with age 6 years. Sleep duration and midpoint of sleep were strongly positively correlated at all ages (R=0.55-0.95). We observed significant negative associations between total electronic media use and TV/DVD watching, while book reading did neither affect the sleep quality score nor sleep duration or midpoint of sleep. We found little evidence for an indirect negative effect of media use on sleep quality via sleep duration or midpoint of sleep, indicating that media use acts independently on sleep duration, midpoint of sleep, and sleep quality. Non-statistically significant associations of sleep duration and midpoint of sleep on sleep quality indicate that these are independent aspects of sleep adequacy. Evidence for this was stronger during free days.

CONCLUSION

Media use acted on sleep quality through a direct effect in a prospective fashion. Thus, we conclude that electronic media use increases the risk for sleep impairments in German preschoolers, while book reading seems to be a safe and healthy alternative.

[Detection of relevant changes in the speaking voice of women measured by the speaking voice profile]

BACKGROUND

 A healthy voice serves us as a basis for communication and an indispensable tool in a modern society with a growing number of vocal-intensive professions. There are indications that the average frequency of the speaking voice of women has decreased in recent years and is approaching that of men in the sense of sociophony. An epidemiological prospective cohort study will investigate the influences of age, personality traits and socio-demographic factors on the speaking voice of women.

MATERIAL AND METHODS

 Within the framework of a standardized examination procedure, the speaking voice of 2478 voice-healthy female participants between 5 and 83 years of age was registered in 4 different intensity levels (softest voice, conversational voice, classroom voice and shouting voice). Subsequently, the collected values for frequency and loudness of the different intensity levels were examined for correlation with age and results from questionnaires on personality (FFFK and BFI-10), on (mental) health (Patient-Health-Questionnaire - PHQ) and on socio-economic status (SES).

RESULTS

 Significant age-related influences on the speaking voice could be demonstrated for all voice intensities. For the personality traits investigated, significant positive correlations between the volume of the calling and speaking voice and extraversion were found. For the frequency of the softest voice and speaking voice, significant correlations were found for the personality traits of extraversion and tolerance. While no significant associations were found between the voice parameters of the speaking voice and the PHQ, it was found that the SES has a significant influence on both frequency and intensity.

CONCLUSION

 In addition to age-related changes, relevant influences of personality traits and the SES on speaking voice parameters in women were confirmed, which should be considered in clinical care of dysphonia.

Impaired visual acuity caused by uncorrected refractive errors and amblyopia in a German paediatric cohort

PURPOSE

This study describes the prevalence of visual impairment caused by uncorrected distance refractive error and the spectacle coverage in a large cohort of German children and adolescents. Furthermore, we determined the prevalence of amblyopia and amblyopia treatment.

METHODS

Optometrists carried out visual acuity (VA) testing, non-cycloplegic autorefraction, VA retesting with the refractive correction obtained by autorefraction, and if necessary subjective refraction and cover-test in 1,874 subjects (901 girls/973 boys), aged 3 to 16 years. Additionally, a questionnaire on the history of previous eye care was completed.

RESULTS

Distance visual impairment (VI) with VA worse than 6/18 Snellen in the better eye was present in 0.5% (95% confidence interval [95% CI]: 0.2% to 0.9%) of children. Logistic regression showed a significant positive association between VI and older age (OR = 1.21, P = 0.03). Gender differences were not found (P = 0.77). The spectacle coverage of all participants was 74.8% (95% CI: 65.2% to 82.8%). Amblyopia was found in 29 participants (1.5%; 95% CI: 1.0% to 2.2%) with no age or sex differences. The causes of unilateral amblyopia (27 cases, 93.1%) were anisometropia in 55.6% of children, strabismus in 25.9% and the combination of these factors in 18.5%. All children with bilateral amblyopia (2 cases, 6.9%) showed bilateral high ametropia. We observed 15 children with current amblyopia, who had been treated with occlusion therapy in the past (62.2%; 95% CI: 42.7% to 83.6%).

CONCLUSIONS

The prevalence of impaired VA caused by uncorrected refractive error and amblyopia is comparable with previous studies conducted in urban areas worldwide. Adding the measurement of refractive error to existing medical check-ups, possibly using autorefraction, would be desirable.

Associations of Green Spaces and Streets in the Living Environment with Outdoor Activity, Media Use, Overweight/Obesity and Emotional Wellbeing in Children and Adolescents

Aspects of the living environment can affect health and wellbeing of children and adolescents. Whereas most previous studies assessed the more distant residential urban environment, less is known on possible effects of the close environment. The present study investigated associations of the proportion of streets and green spaces in the immediate urban living environment (50, 100 and 400 m around the home) with media use, outdoor activity, overweight/obesity and emotional problems in two samples of younger (age 3–10, n = 395) and older children (age 10–19, n = 405). Independently of socioeconomic parameters, a higher proportion of streets was associated with overweight/obesity (in younger and older children), higher media use (in younger children), less outdoor activity and more emotional problems (in older children). Older children’s outdoor activity in winter increased with increasing proportions of green spaces. The observations suggest that the immediate urban living environment is a factor that can affect leisure behavior and health in children.

Parent-child agreement in different domains of child behavior and health

AIM

The present study aimed to investigate and compare parent-child agreement in different domains of child health and behavior.

METHODS

Data were collected between 2011 and 2019 within the framework of the LIFE Child study (Germany). Different subgroups of 10- to 12-year-old children and their parents (n (max) = 692) completed questionnaires on several health behaviors (diet, media use, physical activity, sleep), parameters of health (behavioral strengths and difficulties, psychosomatic complaints), and school grades. Agreement between child and parent reports was evaluated using weighted kappa coefficients. Furthermore, the frequencies of different types of (dis)agreement (parent report > child report, same response, child report > parent report) were assessed and checked for associations with child or parent gender.

RESULTS

Agreement between child and parent reports varied from low to almost perfect, with the greatest levels of agreement for school grades and organized physical activity, and the lowest for dizziness, sleep duration, and the consumption of potatoes. Child gender had no significant effect on parent-child agreement. In contrast, the findings suggest that parent gender had some effect on agreement levels, with higher agreement for certain psychosomatic complaints when parent reports were completed by the mother, and higher agreement for white bread consumption if they were completed by the father. For some of the questionnaire items (especially those relating to behavioral difficulties and psychosomatic complaints, but also to the consumption of individual food products and mobile phone use), the type of (dis)agreement differed depending on child or parent gender.

CONCLUSIONS

The findings suggest that the perceptions and reporting strategies of children and their parents can diverge considerably, in particular for behavior that is not easily observable or measurable.

Reciprocal Longitudinal Associations Between Adolescents' Media Consumption and Sleep

Background/Objective: Associations between adolescents' sleep and their media consumption have been shown in several cross-sectional studies. However, longitudinal investigations are still sparse and have mainly investigated associations between sleep duration and the usage of TV or computer games. The present study explored reciprocal longitudinal relationships between the consumption of different screen-based media and sleep-related problems in German adolescents. Participants: Four hundred sixty-seven 10- to 17-year-old adolescents participated in the LIFE Child Study in Leipzig, Germany. Methods: The consumption of screen-based media (TV or video, computer and Internet, mobile phones) as well as sleep-related problems (problems at bedtime, sleep behavior problems, daytime sleepiness) were assessed at two time points, 12 months apart. Reciprocal longitudinal relations were assessed by multiple regression analyses. All associations were controlled for age, gender, socioeconomic status, and dependent variables at baseline. Results: The consumption times of the different screen-based media were significantly related. Similarly, the different sleep-related problems showed significant interrelations. Most importantly, the analyses revealed significant associations between a high baseline consumption of computer and Internet with more problems at bedtime, as well as more daytime sleepiness at follow-up. Furthermore, baseline daytime sleepiness was associated with a higher consumption of TV or video at follow-up. Conclusions: These results indicate a mutual dependency of media consumption and sleep over time.

Target genes, variants, tissues and transcriptional pathways influencing human serum urate levels

Elevated serum urate levels cause gout and correlate with cardiometabolic diseases via poorly understood mechanisms. We performed a trans-ancestry genome-wide association study of serum urate in 457,690 individuals, identifying 183 loci (147 previously unknown) that improve the prediction of gout in an independent cohort of 334,880 individuals. Serum urate showed significant genetic correlations with many cardiometabolic traits, with genetic causality analyses supporting a substantial role for pleiotropy. Enrichment analysis, fine-mapping of urate-associated loci and colocalization with gene expression in 47 tissues implicated the kidney and liver as the main target organs and prioritized potentially causal genes and variants, including the transcriptional master regulators in the liver and kidney, HNF1A and HNF4A. Experimental validation showed that HNF4A transactivated the promoter of ABCG2, encoding a major urate transporter, in kidney cells, and that HNF4A p.Thr139Ile is a functional variant. Transcriptional coregulation within and across organs may be a general mechanism underlying the observed pleiotropy between urate and cardiometabolic traits.

Genome-wide association meta-analyses and fine-mapping elucidate pathways influencing albuminuria

Increased levels of the urinary albumin-to-creatinine ratio (UACR) are associated with higher risk of kidney disease progression and cardiovascular events, but underlying mechanisms are incompletely understood. Here, we conduct trans-ethnic (n = 564,257) and European-ancestry specific meta-analyses of genome-wide association studies of UACR, including ancestry- and diabetes-specific analyses, and identify 68 UACR-associated loci. Genetic correlation analyses and risk score associations in an independent electronic medical records database (n = 192,868) reveal connections with proteinuria, hyperlipidemia, gout, and hypertension. Fine-mapping and trans-Omics analyses with gene expression in 47 tissues and plasma protein levels implicate genes potentially operating through differential expression in kidney (including TGFB1, MUC1, PRKCI, and OAF), and allow coupling of UACR associations to altered plasma OAF concentrations. Knockdown of OAF and PRKCI orthologs in Drosophila nephrocytes reduces albumin endocytosis. Silencing fly PRKCI further impairs slit diaphragm formation. These results generate a priority list of genes and pathways for translational research to reduce albuminuria.

Stability, Continuity, and Bi-Directional Associations of Parental Feeding Practices and Standardized Child Body Mass Index in Children from 2 to 12 Years of Age

(1) Background: Parental feeding practices are related to child body mass index (BMI, kg/m²) and seem to be a consequence rather than cause of child BMI, but research so far is limited. Stability and continuity of feeding practices, probably explaining changes in food intake and child BMI, remain to be poorly examined. (2) Methods: Feeding practices (i.e., restriction, food as reward, pressure to eat, monitoring) assessed via the Child Feeding Questionnaire, child age, standardized BMI (zBMI), and socio-economic status were measured annually at multiple visits (range 2–8) in a population-based longitudinal cohort study of 1512 parents with their children aged 2 to 12 years. Stability, continuity, and bi-directionality of feeding practices and child zBMI were calculated using correlation coefficients, paired t tests, and cross-lagged panels, respectively. (3) Results: Feeding practices and child zBMI showed moderate to high stability. While continuity was high for restriction, minor temporal changes were observed for other feeding practices and child zBMI. Cross-lags indicated that child zBMI predicted restriction, pressure to eat, and monitoring, while food-rewarding predicted child zBMI only minorly. (4) Conclusions: Parents seem to adapt feeding practices to child zBMI with the exception of food-rewarding.