The epidemiology of acne vulgaris in a multiethnic adolescent population from Rotterdam, the Netherlands: A cross-sectional study.

BACKGROUND: Although acne is a prevalent multifactorial inflammatory skin condition, few studies were performed in multiethnic populations. OBJECTIVES: To study the prevalence and determinants of acne in a multiethnic study at the start of puberty. METHODS: This cross-sectional study is embedded in Generation R, a population-based prospective study from Rotterdam, the Netherlands. Three-dimensional facial photos at the center visit in 2016-2019 (of ∼13-year-olds) were used to grade acne severity using the Global Evaluation of the Acne Severity (GEA). Analyses were stratified by biological sex and explored through chi-square tests and multivariable ordinal logistic regression. RESULTS: A total of 4561 children (51% girls) with a median age of 13.5 (IQR 13.3-13.6) were included. The visible acne prevalence (GEA 2-5) for girls vs boys was 62% vs 45% and moderate-to-severe acne (GEA 3-5) 14% vs 9%. Higher puberty stages (adjusted odds ratios: 1.38 [1.20-1.59] and 2.16 [1.86-2.51] for girls and boys, respectively) and darker skin colors V and VI (adjusted odds ratios: 1.90 [1.17-3.08] and 2.43 [1.67-3.56]) were associated with more severe acne in both sexes, and being overweight in boys (adjusted odds ratio: 1.58 [1.15-2.17]). LIMITATIONS: Cross-sectional design. CONCLUSIONS: Acne prevalence was high at the age of 13 years and was associated with advanced puberty, darker skin color, and weight status.

Prospective associations between early childhood parental feeding practices and eating disorder symptoms and disordered eating behaviors in adolescence.

OBJECTIVE: Nonresponsive parental feeding practices are associated with poorer appetite self-regulation in children. It is unknown whether this relationship extends beyond childhood to be prospectively associated with the onset of eating disorder (ED) symptoms in adolescence. This exploratory study therefore investigated prospective associations between early childhood parental feeding practices and adolescent ED symptoms and disordered eating behaviors. METHODS: Data were from two population-based cohorts with harmonized measures: Generation R (Netherlands; n = 4900) and Gemini (UK; n = 2094). Parents self-reported their pressure to eat, restriction and instrumental feeding (i.e., using food as a reward) at child age 4-5 years. Adolescents self-reported their compensatory behaviors (e.g., fasting, purging), binge-eating symptoms, restrained eating, uncontrolled eating, and emotional eating at 12-14 years. Associations between feeding practices and ED symptoms were examined separately in each cohort using generalized linear models. RESULTS: In Gemini, pressure to eat in early childhood was associated with adolescents engaging in compensatory behaviors. In Generation R, parental restriction was associated with adolescents engaging in compensatory behaviors, restrained eating, uncontrolled eating, and emotional eating. Instrumental feeding was associated with uncontrolled eating and emotional eating in Generation R. DISCUSSION: Nonresponsive parental feeding practices were associated with a greater frequency of specific ED symptoms and disordered eating in adolescence, although effect sizes were small and findings were inconsistent between cohorts. Potentially, the cultural and developmental context in which child-parent feeding interactions occur is important for ED symptoms. Further replication studies are required to better understand parents' role in the development and maintenance of ED-related symptoms. PUBLIC SIGNIFICANCE: Prospective research examining how early childhood parental feeding practices might contribute to adolescent ED symptoms is limited. In two population-based cohorts, nonresponsive feeding practices (restriction, instrumental feeding, pressure to eat) predicted increased frequency of some ED symptoms and disordered eating behaviors in adolescence, although associations were small and further replication is required. Findings support the promotion of responsive feeding practices, which may benefit young children's developing relationship with food.

Reducing behavior problems in children born after an unintended pregnancy: the generation R study.

OBJECTIVES: To examine differences in behavior problems between children from intended versus unintended pregnancies, and to estimate how much the difference in problem behavior would be reduced if postnatal depression was eliminated and social support was increased within 6 months after birth. METHODS: Data from the Generation R Study were used, a population-based birth cohort in Rotterdam, the Netherlands (N = 9621). Differences in child internalizing and externalizing behavior at ages 1.5, 3, 6, 9 and 13 years between pregnancy intention groups were estimated using linear regression. Associations of postnatal depression and social support with internalizing and externalizing problems were also estimated using linear regression. Child behavior outcomes where compared before and after modelling a situation in which none of the mothers experienced a postnatal depression and all mother experienced high social support. RESULTS: Most pregnancies (72.9%) were planned, 14.8% were unplanned and wanted, 10.8% were unplanned with initially ambivalent feelings and 1.5% with prolonged ambivalent feelings. Children from unplanned pregnancies had more internalizing and externalizing problems at all ages as compared to children from a planned pregnancy, especially when ambivalent feelings were present. Hypothetically eliminating on postnatal depression reduced the differences in internalizing and externalizing problems by 0.02 to 0.16 standard deviation. Hypothetically increasing social support did not significantly reduce the difference in internalizing and externalizing problems. CONCLUSIONS: Children from an unplanned pregnancy have more behavior problems, in particular when mothers had prolonged ambivalent feelings. Eliminating postnatal depression may help to reduce the inequality in child behavior related to pregnancy intention.

Bidirectional associations between mental health problems and language ability across 8 years of childhood.

Research examining the development of behavior, emotions and language, and their intertwining is limited as only few studies had a longitudinal design, mostly with a short follow-up period. Moreover, most studies did not evaluate whether internalizing symptoms and externalizing symptoms are independently associated with language ability. This study examines bidirectional associations between internalizing symptoms, externalizing symptoms and language ability in childhood in a large, population-based cohort. Longitudinal data from the Millennium Cohort Study, a cohort of children in the United Kingdom followed from birth to 11 years (n = 10,878; 50.7% boys), were analyzed. Internalizing and externalizing symptoms were based on parent reports. Language ability (higher scores reflecting poorer ability) was assessed by trained interviewers at ages 3, 5, 7 and 11 years. Structural Equation Models (SEM) were performed, including random-intercept cross-lagged panel models (RI-CLPM) and cross-lagged panel models (CLPM). Internalizing symptoms, externalizing symptoms and language ability were stable over time and co-occur with each other from early life onwards. Over time, externalizing symptoms in early childhood were associated with less growth in language skills and with increases in internalizing symptoms. In late childhood, language ability was negatively associated with later internalizing and externalizing symptoms. The early start, co-occurrence and persistent nature of internalizing symptoms, externalizing symptoms and (poorer) language ability highlights the importance of comprehensive assessments in young children who present problems in one of these domains. Specifically, among children in the early grades of elementary school, those with language difficulties may benefit from careful monitoring as they are more likely to develop difficulties in behavior and emotions.

The gut microbiome and child mental health: A population-based study.

The link between the gut microbiome and the brain has gained increasing scientific and public interest for its potential to explain psychiatric risk. While differences in gut microbiome composition have been associated with several mental health problems, evidence to date has been largely based on animal models and human studies with modest sample sizes. In this cross-sectional study in 1,784 ten-year-old children from the multi-ethnic, population-based Generation R Study, we aimed to characterize associations of the gut microbiome with child mental health problems. Gut microbiome was assessed from stool samples using 16S rRNA sequencing. We focused on overall psychiatric symptoms as well as with specific domains of emotional and behavioral problems, assessed via the maternally rated Child Behavior Checklist. While we observed lower gut microbiome diversity in relation to higher overall and specific mental health problems, associations were not significant. Likewise, we did not identify any taxonomic feature associated with mental health problems after multiple testing correction, although suggestive findings indicated depletion of genera previously associated with psychiatric disorders, including Hungatella, Anaerotruncus and Oscillospiraceae. The identified compositional abundance differences were found to be similar across all mental health problems. Finally, we did not find significant enrichment for specific microbial functions in relation to mental health problems. In conclusion, based on the largest sample examined to date, we do not find clear evidence of associations between gut microbiome diversity, taxonomies or functions and mental health problems in the general pediatric population. In future, the use of longitudinal designs with repeated measurements of microbiome and psychiatric outcomes will be critical to identify whether and when associations between the gut microbiome and mental health emerge across development and into adulthood.

Fetal and infant growth patterns, sleep, and 24-h activity rhythms: a population-based prospective cohort study in school-age children.

The study objective was to explore associations of fetal and infant weight patterns and preterm birth with sleep and 24-h activity rhythm parameters at school-age. In our prospective population-based study, 1327 children were followed from birth to age 10-15 years. Fetal weight was estimated using ultrasound in the second and third trimester of pregnancy. Birth weight and gestational age were available from midwife registries. Infant weight was measured at 6, 12 and 24 months. Fetal and infant weight acceleration or deceleration were defined as a change of >0.67 standard deviation between the corresponding age intervals. At school-age, sleep duration, sleep efficiency, wake after sleep onset, social jetlag, inter-daily stability, and intra-daily variability were assessed using tri-axial wrist actigraphy for 9 consecutive nights. We observed that low birth weight (<2500 g) was associated with 0.24 standard deviation (95% confidence interval [CI] 0.04; 0.43) longer sleep duration compared to normal weight. Compared to normal growth, growth deceleration in fetal life and infancy was associated with 0.40 standard deviation (95% CI 0.07; 0.73) longer sleep duration, 0.44 standard deviation (95% CI 0.14; 0.73) higher sleep efficiency, and -0.41 standard deviation (95% CI -0.76; -0.07) shorter wake after sleep onset. A pattern of normal fetal growth followed by infant growth acceleration was associated with -0.40 standard deviation (95% CI -0.61; -0.19) lower inter-daily stability. Preterm birth was not associated with any sleep or 24-h rhythm parameters. Our findings showed that children with fetal and infant growth restriction had longer and more efficient sleep at school-age, which may be indicative of an increased need for sleep for maturational processes and development after a difficult start in life.

Dietary patterns, brain morphology and cognitive performance in children: Results from a prospective population-based study.

Dietary patterns in childhood have been associated with child neurodevelopment and cognitive performance, while the underlying neurobiological pathway is unclear. We aimed to examine associations of dietary patterns in infancy and mid-childhood with pre-adolescent brain morphology, and whether diet-related differences in brain morphology mediate the relation with cognition. We included 1888 and 2326 children with dietary data at age one or eight years, respectively, and structural neuroimaging at age 10 years in the Generation R Study. Measures of brain morphology were obtained using magnetic resonance imaging. Dietary intake was assessed using food-frequency questionnaires, from which we derived diet quality scores based on dietary guidelines and dietary patterns using principal component analyses. Full scale IQ was estimated using the Wechsler Intelligence Scale for Children-Fifth Edition at age 13 years. Children with higher adherence to a dietary pattern labeled as 'Snack, processed foods and sugar' at age one year had smaller cerebral white matter volume at age 10 (B = -4.3, 95%CI -6.9, -1.7). At age eight years, higher adherence to a 'Whole grains, soft fats and dairy' pattern was associated with a larger total brain (B = 8.9, 95%CI 4.5, 13.3), and larger cerebral gray matter volumes at age 10 (B = 5.2, 95%CI 2.9, 7.5). Children with higher diet quality and better adherence to a 'Whole grains, soft fats and dairy' dietary pattern at age eight showed greater brain gyrification and larger surface area, clustered primarily in the dorsolateral prefrontal cortex. These observed differences in brain morphology mediated associations between dietary patterns and IQ. In conclusion, dietary patterns in early- and mid-childhood are associated with differences in brain morphology which may explain the relation between dietary patterns and neurodevelopment in children.

Inguinal hernia surgery learning curves by associate clinicians.

BACKGROUND: Open inguinal hernia repair is the most commonly performed procedure in general surgery in sub-Saharan Africa, but data on its learning curve are lacking. This study evaluated the learning curve characteristics to improve surgical training and enable scaling up hernia surgery in low- and middle-income countries. METHODS: Logbook data of associate clinicians enrolled in a surgical training program in Sierra Leone were collected and their first 55 hernia surgeries following the Bassini technique (herniorrhaphies) were analyzed in cohorts of five cases. Studied variables were gradient of decline of operating time, variation in operating time, and length of stay (LOS). Eleven subsequent cohorts of each five herniorrhaphies were investigated. RESULTS: Seventy-five trainees enrolled in the training program between 2011 and 2020 were eligible for inclusion. Thirty-one (41.3%) performed the minimum of 55 herniorrhaphies, and had also complete personal logbook data. Mean operating times dropped from 79.6 (95% CI 75.3-84.0) to 48.6 (95% CI 44.3-52.9) minutes between the first and last cohort, while standard deviation in operating time nearly halved to 15.4 (95% CI 11.7-20.0) minutes, and LOS was shortened by 3 days (8.5 days, 95%CI 6.1-10.8 vs. 5.4 days, 95% 3.1-7.6). Operating times flattened after 31-35 cases which corresponded with 1.5 years of training. CONCLUSIONS: The learning curve of inguinal hernia surgery for associate clinicians flattens after 31-35 procedures. Training programs can be tailored based on this finding. The recorded learning curve may serve as a baseline for future training techniques.

Maternal sensitivity in early childhood and body mass index in adolescence: A population-based study on the role of self-regulation as a mediator.

Maternal sensitivity has been implicated in various aspects of child health and development, including overweight. However, long-term effects, the role of paternal sensitivity and the explanatory pathways are unclear. This study examined whether maternal sensitivity in early childhood is prospectively associated with adolescent body mass index and whether children's self-regulation mediates this relation. Data from 540 children and their mothers were available from a large cohort study in the Netherlands. Maternal sensitivity was assessed at child ages 1, 3, and at 4 years paternal sensitivity was also included. Children's self-regulation skills were observed at age 3, eating behaviour was assessed at 10 years, and child BMI was measured at 13 years. Longitudinal structural equation modelling was applied. The cross-sectional association between maternal sensitivity and child self-regulation was significant, while lower levels of self-regulation and higher levels of food responsiveness and restrained eating predicted a higher child BMI at 13 years. Furthermore, a direct association of paternal sensitivity at 4 years with BMI at 13 years was found, but only in girls. Maternal sensitivity was not directly associated with child BMI after adjusting for covariates. Our findings showed the importance of self-regulation in the early years for subsequent weight development. Nevertheless, as self-regulation could not explain the relationship between parenting and child weight, research should focus on the contribution of other contextual factors, such as feeding styles and the social environment, to this relationship.

An epigenome-wide association study of child appetitive traits and DNA methylation.

The etiology of childhood appetitive traits is poorly understood. Early-life epigenetic processes may be involved in the developmental programming of appetite regulation in childhood. One such process is DNA methylation (DNAm), whereby a methyl group is added to a specific part of DNA, where a cytosine base is next to a guanine base, a CpG site. We meta-analyzed epigenome-wide association studies (EWASs) of cord blood DNAm and early-childhood appetitive traits. Data were from two independent cohorts: the Generation R Study (n = 1,086, Rotterdam, the Netherlands) and the Healthy Start study (n = 236, Colorado, USA). DNAm at autosomal methylation sites in cord blood was measured using the Illumina Infinium HumanMethylation450 BeadChip. Parents reported on their child's food responsiveness, emotional undereating, satiety responsiveness and food fussiness using the Children's Eating Behaviour Questionnaire at age 4-5 years. Multiple regression models were used to examine the association of DNAm (predictor) at the individual site- and regional-level (using DMRff) with each appetitive trait (outcome), adjusting for covariates. Bonferroni-correction was applied to adjust for multiple testing. There were no associations of DNAm and any appetitive trait when examining individual CpG-sites. However, when examining multiple CpGs jointly in so-called differentially methylated regions, we identified 45 associations of DNAm with food responsiveness, 7 associations of DNAm with emotional undereating, 13 associations of DNAm with satiety responsiveness, and 9 associations of DNAm with food fussiness. This study shows that DNAm in the newborn may partially explain variation in appetitive traits expressed in early childhood and provides preliminary support for early programming of child appetitive traits through DNAm. Investigating differential DNAm associated with appetitive traits could be an important first step in identifying biological pathways underlying the development of these behaviors.

Child Autistic Traits, Food Selectivity, and Diet Quality: A Population-Based Study.

BACKGROUND: Children with Autism Spectrum Disorders (ASDs) tend to be selective in their food intake, which may compromise their diet quality. While ASD diagnoses capture severe levels of impairment, autistic traits vary on a continuum throughout the population. Yet, little is known about how autistic traits relate to diet quality at the population level. OBJECTIVES: This study examines the association between autistic traits in early childhood and diet quality in mid-childhood and explores the mediating role of food selectivity. METHODS: Participants were children (n = 4092) from the population-based Generation R Study. Parents reported their child's autistic traits at 1.5, 3, and 6 years; food selectivity at 4 years; and food intake at 8 years, from which a diet quality score was derived. Associations of autistic traits and the autistic trait trajectory (identified using Latent Class Growth Modelling) with diet quality were examined using multiple linear regression models. The indirect effect of food selectivity in the association between autistic traits at 1.5 years and diet quality was examined using mediation analysis. RESULTS: Autistic traits were associated with diet quality (e.g., 1.5 years: ß = -0.09; 95% CI: -0.13 to -0.06). Two classes captured the autistic trait trajectories from 1.5 to 6 years: children with "low and stable" (95%) and "high and increasing" (5%) mean scores. Children in the high and increasing group had poorer diet quality than those in the low and stable group (ß = -0.28; 95% CI: -0.44 to -0.11). Food selectivity mediated the association between autistic traits at 1.5 years and diet quality at 8 years (ßindirect = -0.03; 95% CI: -0.03 to -0.02). CONCLUSIONS: Autistic traits in early childhood are associated with poorer diet quality in mid-childhood, and food selectivity appears to mediate this association. Interventions intended to optimize nutrition in children with elevated autistic traits may integrate behavioral strategies to support parents' responding to their child's food selectivity.

Trajectories of socioeconomic inequality in early child development: a cohort analysis.

BACKGROUND: Addressing socioeconomic inequalities in early child development (ECD) is key to reducing the intergenerational transmission of health inequalities. Yet, little is known about how socioeconomic inequalities in ECD develop over the course of childhood. Our study aimed to describe how inequalities in ECD by maternal education develop from infancy to middle childhood. METHODS: We used data from Generation R, a prospective population-based cohort study in The Netherlands. Language skills were measured at ages 1, 1.5, 2, 3, and 4 years, using the Minnesota Child Development Inventory. Socioemotional (i.e. internalizing and externalizing) problems were measured at ages 1.5, 3, 5 and 9 years using the Child Behavior Checklist. We estimated inequalities in language skills and socioemotional problems across the above-mentioned ages, using linear mixed models with standardized scores at each wave. We used maternal education as indicator of socioeconomic position. RESULTS: Children of less educated mothers had more reported internalizing (B = 0.72, 95%CI = 0.51;0.95) and externalizing (B = 0.25, 95%CI = 0.10;0.40) problems at age 1.5 years, but better (caregiver reported) language skills at 1 year (B = 0.50, 95%CI = 0.36;0.64) than children of high educated mothers. Inequalities in internalizing and externalizing problems decreased over time. Inequalities in language scores reversed at age 2, and by the time children were 4 years old, children of less educated mothers had substantially lower language skills than children of high educated mothers (B = -0.38, 95%CI = -0.61;-0.15). CONCLUSIONS: Trajectories of socioeconomic inequality in ECD differ by developmental domain: whereas inequalities in socioemotional development decreased over time, inequalities increased for language development. Children of less educated mothers are at a language disadvantage even before entering primary education, providing further evidence that early interventions are needed.

Early life stress and behavior problems in early childhood: Investigating the contributions of child temperament and executive functions to resilience.

This preregistered study examined whether child temperament and executive functions moderated the longitudinal association between early life stress (ELS) and behavior problems. In a Dutch population-based cohort (n = 2803), parents reported on multiple stressors (age 0-6 years), child temperament (age 5), and executive functions (age 4), and teachers rated child internalizing and externalizing problems (age 7). Results showed that greater ELS was related to higher levels of internalizing and externalizing problems, with betas reflecting small effects. Lower surgency buffered the positive association of ELS with externalizing problems, while better shifting capacities weakened the positive association between ELS and internalizing problems. Other child characteristics did not act as moderators. Findings underscore the importance of examining multiple protective factors simultaneously.

Clustering of characteristics associated with unplanned pregnancies: the generation R study.

BACKGROUND: Unplanned or unintended pregnancies form a major public health concern because they are associated with unfavorable birth outcomes as well as social adversity, stress and depression among parents-to-be. Several risk factors for unplanned pregnancies in women have previously been identified, but studies usually take a unidimensional approach by focusing on only one or few factors, disregarding the possibility that predictors might cluster. Furthermore, data on predictors in men are largely overlooked. The purpose of this study is to determine predictors of unplanned versus planned pregnancy, to determine predictors of ambivalent feelings regarding pregnancy, and to investigate how characteristics of men and women with an unplanned pregnancy cluster together. METHODS: This study was embedded in Generation R, a multiethnic population-based prospective cohort from fetal life onwards. Pregnancy intention was reported by 7702 women and 5367 partners. Information on demographic, mental, physical, social, and sexual characteristics was obtained. Logistic regression, multinomial regression and cluster analyses were performed to determine characteristics that were associated with an unplanned pregnancy, with ambivalent feelings regarding the unplanned pregnancy and the co-occurrence of characteristics in women and men with unplanned pregnancy. RESULTS: Twenty nine percent of the pregnancies were unplanned. Logistic regression analyses showed that 42 of 44 studied predictors were significantly associated with unplanned pregnancy. The most important predictors were young age, migration background, lower educational level, lower household income, financial difficulties, being single, lower cognitive ability, drug use prior to pregnancy, having multiple sexual partners in the year prior to the pregnancy, younger age of first sexual contact and a history of abortion. Multinomial regression analyses showed that a Turkish or Moroccan background, Islamic religion, little financial opportunities, being married, having ≥3 children, high educational level, more mental health and social problems and older age of first sexual contact were associated with prolonged ambivalent feelings regarding pregnancy. Different combinations of characteristics were observed in the four clusters of women and men with unplanned pregnancy. CONCLUSIONS: Many predictors are related with unplanned pregnancies, ambivalent feelings toward the pregnancy, and we identified very heterogeneous groups of women and men with unplanned pregnancies. This calls for heterogeneous measures to prevent unplanned pregnancies.

Double advantage of parental education for child educational achievement: the role of parenting and child intelligence.

BACKGROUND: Parental education is one of the best predictors of child school achievement. Higher parental education is not only associated with higher child intelligence, but children from highly educated parents also perform better in school due to other family related factors. This study evaluates the relation between parental education, child non-verbal intelligence and parenting practices with child school achievement. METHODS: Longitudinal data from a large population-based, multi-ethnic cohort of children in the Netherlands (63% Dutch origin) followed from birth to age 13 years (3547 children; 52.3% girls) were analyzed. School achievement was measured at the end of primary school (12 years of age) with a national Dutch academic test score. Parental education was assessed at age 3 years. The non-verbal intelligence of the child was measured at age 6 years and a full intelligence was measured at age 13 years. Maternal and paternal family routines, harsh parenting and corporal punishment were assessed in early and mid-childhood. Mediation analysis was performed with the G-formula and Structural Equation Models. RESULTS: Child intelligence partially mediated [B indirect effect =0.54 95% CI (0.46, 0.62) P < 0.001] the association between parental education and child school achievement. Independent of intelligence, family routines [B indirect effect =0.04 95% CI (0.01, 0.07) P < 0.01], but not harsh parenting mediated this association. CONCLUSIONS: Higher parental education was associated with better school achievement through two independent mechanisms, through higher intelligence of the child and parenting practices.

The relation between harsh parenting and bullying involvement and the moderating role of child inhibitory control: A population-based study.

Harsh parenting has been linked to children's bullying involvement in three distinct roles: perpetrators, targets (of bullying), and perpetrator-targets. To understand how the same parenting behavior is associated with three different types of bulling involvement, we examined the moderating roles of children's inhibitory control and sex. In addition, we differentiated between mothers' and fathers' harsh parenting. We analyzed multi-informant questionnaire data from 2131 families participating in the Dutch Generation R birth cohort study. When children were three years old, parents reported on their own harsh parenting practices. When children were four, mothers reported on their children's inhibitory control. At child age six, teachers reported on children's bullying involvement. Our results revealed that fathers', and not mothers', harsh parenting increased the odds of being a perpetrator. No moderation effects with children's inhibitory control and sex were found for the likelihood of being a perpetrator. Moderation effects were present for the likelihood of being a target and a perpetrator-target, albeit only with mothers' harsh parenting. Specifically, for boys with lower-level inhibitory control problems, mothers' harsh parenting increased the odds of being a target. In contrast, for boys with higher-level inhibitory control problems, mothers' harsh parenting decreased the odds of being a target. Furthermore, for girls with higher-level inhibitory control problems, mothers' harsh parenting increased the odds of being a perpetrator-target. Overall, our results underscore the importance of differentiating by children's cognitive skills and by parent and child sex to fully understand how harsh parenting and bullying involvement are related.

Smartphone Use Associated with Refractive Error in Teenagers: The Myopia App Study.

PURPOSE: To investigate the association between smartphone use and refractive error in teenagers using the Myopia app. DESIGN: Cross-sectional population-based study. PARTICIPANTS: A total of 525 teenagers 12 to 16 years of age from 6 secondary schools and from the birth cohort study Generation R participated. METHODS: A smartphone application (Myopia app; Innovattic) was designed to measure smartphone use and face-to-screen distance objectively and to pose questions about outdoor exposure. Participants underwent cycloplegic refractive error and ocular biometry measurements. Mean daily smartphone use was calculated in hours per day and continuous use as the number of episodes of 20 minutes on screen without breaks. Linear mixed models were conducted with smartphone use, continuous use, and face-to-screen distance as determinants and spherical equivalent of refraction (SER) and axial length-to-corneal radius (AL:CR) ratio as outcome measures stratified by median outdoor exposure. MAIN OUTCOME MEASURES: Spherical equivalent of refraction in diopters and AL:CR ratio. RESULTS: The teenagers on average were 13.7 ± 0.85 years of age, and myopia prevalence was 18.9%. During school days, total smartphone use on average was 3.71 ± 1.70 hours/day and was associated only borderline significantly with AL:CR ratio (ß = 0.008; 95% confidence interval [CI], -0.001 to 0.017) and not with SER. Continuous use on average was 6.42 ± 4.36 episodes of 20-minute use without breaks per day and was associated significantly with SER and AL:CR ratio (ß = -0.07 [95% CI, -0.13 to -0.01] and ß = 0.004 [95% CI, 0.001-0.008], respectively). When stratifying for outdoor exposure, continuous use remained significant only for teenagers with low exposure (ß = -0.10 [95% CI, -0.20 to -0.01] and ß = 0.007 [95% CI, 0.001-0.013] for SER and AL:CR ratio, respectively). Smartphone use during weekends was not associated significantly with SER and AL:CR ratio, nor was face-to-screen distance. CONCLUSIONS: Dutch teenagers spent almost 4 hours per day on their smartphones. Episodes of 20 minutes of continuous use were associated with more myopic refractive errors, particularly in those with low outdoor exposure. This study suggested that frequent breaks should become a recommendation for smartphone use in teenagers. Future large longitudinal studies will allow more detailed information on safe screen use in youth.

The experience of life events and body composition in middle childhood: a population-based study.

While studies suggest potential influences of childhood adversities on obesity development in adulthood, less is known about the short-term association in children. We examined the association between a wide range of life events experienced in the first ten years of life (including maltreatment and milder adversities) and body composition in 5333 ten-year old Dutch children. In structured interviews, mothers retrospectively reported on their children's experience of 24 events. BMI was calculated, and fat mass index and fat free mass index were determined by dual-x-ray absorptiometry scanning. Linear regressions showed that, unadjusted, a higher number of life events was associated with higher BMI and body composition. However, associations attenuated to non-significance after adjustment for covariates. Similar findings were observed for maltreatment and milder life events. Thus, the number of experienced life events was not associated with body composition in middle childhood. Rather, other factors, like socioeconomic conditions, accounted for the relationship between life events and weight development in children.

The longitudinal relationship between set-shifting at 4 years of age and eating disorder related features at 9 years of age in the general pediatric population.

BACKGROUND: Individuals with anorexia nervosa (AN) tend to have rigid thoughts and behaviors regarding their body weight, body image, and eating habits. While a diagnosis of AN implies severe levels of impairment, AN traits can vary on a continuum within the population. However, little is known about how early markers of AN relate to rigid thought patterns and to what extent cognitive rigidity is already present in early childhood. We examined the association of set-shifting abilities as a measure of cognitive flexibility in preadolescents with AN-related features. METHODS: Participants included 3,987 children participating in the Generation R Study, a Dutch population-based birth cohort. Set-shifting abilities (mother report) were assessed at 4 years of age, body mass index (BMI) was determined at 4 and 9 years and restrictive eating patterns (mother report) and body image (child report) were assessed at 9 years. RESULTS: Lower set-shifting abilities at 4 years were associated with a lower BMI (ß = -.44, p = 2.2 × 10-4 ) in girls, and more restrictive eating (ß = 0.15, p = 2.7 × 10-6 ) in both boys and girls at 9 years of age. Moreover, set-shifting at age 4 was not associated with body image at age 9. CONCLUSION: These findings contribute to the idea that the association between set-shifting problems and AN-related features are present early in childhood, prior to the typical range of the onset of eating disorders (EDs). Longitudinal studies that capture the peak age for the development of EDs will be important to assess whether early cognitive inflexibility is an early marker of AN.

The role of food selectivity in the association between child autistic traits and constipation.

OBJECTIVE: This study examines the association between child autistic traits and constipation symptoms, and explores whether this association is mediated by food selectivity. METHOD: The sample included participants (N = 2,818) from the population-based birth cohort, Generation R (Rotterdam, the Netherlands). Parents reported their child's autistic traits at 6 years (using the Social Responsiveness Scale), food selectivity at 10 years (using the Stanford Feeding Questionnaire) and the frequency and severity of constipation symptoms they experienced at 10 years (using the ROME III functional constipation diagnostic criteria). Mediation analyses tested mediation through food selectivity in the association of autistic traits and the number of constipation symptoms, adjusting for covariates. RESULTS: There was a positive association between parent-reported child autistic traits and constipation symptoms (r = 0.08, p < .001). We identified a significant indirect effect of autistic traits on constipation symptoms through food selectivity (ß = 0.008, 95% Confidence Interval: 0.002, 0.014). DISCUSSION: This study provides empirical support for the mediating role of food selectivity in the association between autistic traits and constipation. Behavioral interventions aimed to target food selectivity and support families of children with autistic traits may bolster conventional medical and nutritional treatments to alleviate gastrointestinal symptoms like constipation.