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Purpose of Review To examine the evidence that the dietary quality of children changed between the period preceding the COVID-19 pandemic and the first year during the pandemic. Recent Findings A systematic review of the evidence for dietary changes occurring as a result of the pandemic-related restrictions, in Part I of this article, yielded 38 original research articles. These articles had conflicting results, some describing improvements in overall quality and some describing deteriorations. As a whole the studies were characterized by a low study quality, and children were poorly represented. Taken together, these studies do not provide enough evidence to draw conclusions about whether dietary habits changed or not as a result of the pandemic. However, in a wider, narrative review of the psychosocial changes occurring as a result of the COVID-19 pandemic, and the known associations of these factors with a dietary intake in Part II, we conclude that there is a reason to expect that the dietary quality of children might have been adversely affected by the COVID-19 pandemic. Summary One the one hand, the literature fails to provide conclusive evidence on changes in the dietary quality of children resulting from the COVID-19 pandemic. On the other hand, the broader literature supports the hypothesis that children’s dietary quality will have declined during the pandemic. Taken together, we urgently need more high-quality research on children’s changes in dietary intake occurring over the pandemic. This will provide important information on whether any potential long-term consequences of such changes, if they exist, need to be examined and ameliorated.

BACKGROUND Patients with chiasmatic-hypothalamic low-grade glioma (CHLGG) have frequent MRIs with gadolinium-based contrast agents (GBCA) for disease monitoring. Cumulative gadolinium deposition in the brains of children is a potential concern. The purpose of this study is to evaluate whether MRI with GBCA is necessary for determining radiographic tumor progression in children with CHLGG. METHODS Children who were treated for progressive CHLGG from 2005 to 2019 at Texas Children's Cancer Center were identified. Pre- and post-contrast MRI sequences were separately reviewed by one neuroradiologist who was blinded to the clinical course. Three dimensional measurements and tumor characteristics were evaluated. Radiographic progression was defined as a 25% increase in size (product of two largest dimensions) compared with baseline or best response after initiation of therapy. RESULTS A total of 28 patients with progressive CHLGG were identified with a total of 683 MRIs with GBCA reviewed (mean 24 MRIs/patient; range, 11-43 MRIs). Radiographic progression was observed 92 times, 91 (99%) on noncontrast and 90 (98%) on contrast imaging. Sixty-seven progressions necessitating management changes were identified in all (100%) noncontrast sequences and 66 (99%) contrast sequences. Tumor growth > 2 mm in any dimension was identified in 184/187 (98%) noncontrast and 181/187 (97%) with contrast imaging. Metastatic tumors were better visualized on contrast imaging in 4/7 (57%). CONCLUSION MRI without GBCA effectively identifies patients with progressive disease. When imaging children with CHLGG, eliminating GBCA should be considered unless monitoring patients with metastatic disease.

PURPOSE OF REVIEW: Current feeding advice to prevent pediatric obesity focusses on caregiver feeding behaviors. This review integrates newer data showing that child appetitive traits also have a genetic component. RECENT FINDINGS: Caregiver feeding behaviors robustly correlate with child eating behaviors; however there is also a strong heritable component. SUMMARY: The satiety cascade delineates the biological drive underlying hunger, satiation and satiety. Innate individual differences exist for the components of the satiety cascade, which may explain the heritability of child eating behaviors. However, given the correlation of caregiver feeding behaviors with child eating behaviors any etiological model should include both genetic/biological components and environmental. Integrating the biological etiology of child eating behaviors into the current environmental model has implications for tailoring feeding advice which needs to move from a “one size fits all” approach, to one that is tailored to individual differences in children’s biological drives to appetite.

PURPOSE OF REVIEW: This narrative review describes the evidence for both genetic and environmental influences on child appetitive traits, and suggests ways of thinking about how these interact and correlate to influence how a child eats. RECENT FINDINGS: Emerging evidence from social network analysis, and from longitudinal studies questioning the direction of association between parent feeding behaviors and child obesity risk, suggest that children’s genes may shape the environmental risk for obesity that they are exposed to. SUMMARY: There is strong evidence that child appetitive traits are both heritable, and shaped by the environment. Instead of thinking about how genetic and environmental factors operate independently on each appetitive trait, research needs to expand the current paradigm to examine how genes and environments interact and shape each other.

Various policies to reduce sugar-sweetened beverages (SSBs) consumption in children have been implemented. Here, we review the evidence on whether these policies are effective in reducing SSB intake and whether a reduction in SSB intake results in a concomitant reduction in child obesity. We also highlight ethical concerns with such efforts. The evidence supporting relationship between SSB consumption and child body mass index (BMI) is consistently small and lacks causality. The effects of policies are unclear; taxation has no clear relationship to SSB purchasing, innovative marketing outlets make it difficult to examine the effects of restricting marketing on SSB consumption, and there is no evidence that reducing SSB availability in schools decreases consumption. Research studies with rigorous and reproducible study designs are needed to examine whether reducing SSB consumption reduces child obesity, and to identify implementable policies that not only reduce SSB consumption but also child weight.

BackgroundTwin and sibling studies have identified specific cognitive phenotypes that may mediate the association between genes and the clinical symptoms of attention deficit hyperactivity disorder (ADHD). ADHD is also associated with lower IQ scores. We aimed to investigate whether the familial association between measures of cognitive performance and the clinical diagnosis of ADHD is mediated through shared familial influences with IQ.MethodMultivariate familial models were run on data from 1265 individuals aged 6–18 years, comprising 920 participants from ADHD sibling pairs and 345 control participants. Cognitive assessments included a four-choice reaction time (RT) task, a go/no-go task, a choice–delay task and an IQ assessment. The analyses focused on the cognitive variables of mean RT (MRT), RT variability (RTV), commission errors (CE), omission errors (OE) and choice impulsivity (CI).ResultsSignificant familial association (rF) was confirmed between cognitive performance and both ADHD (rF=0.41–0.71) and IQ (rF=−0.25 to −0.49). The association between ADHD and cognitive performance was largely independent (80–87%) of any contribution from etiological factors shared with IQ. The exception was for CI, where 49% of the overlap could be accounted for by the familial variance underlying IQ.ConclusionsThe aetiological factors underlying lower IQ in ADHD seem to be distinct from those between ADHD and RT/error measures. This suggests that lower IQ does not account for the key cognitive impairments observed in ADHD. The results have implications for molecular genetic studies designed to identify genes involved in ADHD.

Previous studies have documented the primarily genetic aetiology for the stronger phenotypic covariance between reading disability and ADHD inattention symptoms, compared to hyperactivity-impulsivity symptoms. In this study, we examined to what extent this covariation could be attributed to "generalist genes" shared with general cognitive ability or to "specialist" genes which may specifically underlie processes linking inattention symptoms and reading difficulties. We used multivariate structural equation modeling on IQ, parent and teacher ADHD ratings and parent ratings on reading difficulties from a general population sample of 1312 twins aged 7.9-10.9 years. The covariance between reading difficulties and ADHD inattention symptoms was largely driven by genetic (45%) and child-specific environment (21%) factors not shared with IQ and hyperactivity-impulsivity; only 11% of the covariance was due to genetic effects common with IQ. Aetiological influences shared among all phenotypes explained 47% of the variance in reading difficulties. The current study, using a general population sample, extends previous findings by showing, first, that the shared genetic variability between reading difficulties and ADHD inattention symptoms is largely independent from genes contributing to general cognitive ability and, second, that child-specific environment factors, independent from IQ, also contribute to the covariation between reading difficulties and inattention symptoms.

BackgroundAttention deficit hyperactivity disorder (ADHD) shows a strong phenotypic and genetic association with reaction time (RT) variability, considered to reflect lapses in attention. Yet we know little about whether this aetiological pathway is shared with other affected cognitive processes in ADHD, such as lower IQs or the generally slower responses (mean RTs). We aimed to address the question of whether a shared set of genes exist that influence RT variability, mean RT, IQ and ADHD symptom scores, or whether there is evidence of separate aetiological pathways.MethodMultivariate structural equation modelling on cognitive tasks data (providing RT data), IQ and ADHD ratings by parents and teachers collected on general population sample of 1314 twins, at ages 7–10 years.ResultsMultivariate structural equation models indicated that the shared genetic influences underlying both ADHD symptom scores and RT variability are also shared with those underlying mean RT, with both types of RT data largely indexing the same underlying liability. By contrast, the shared genetic influences on ADHD symptom scores and RT variability (or mean RT) are largely independent of the genetic influences that ADHD symptom scores share with IQ.ConclusionsThe finding of unique aetiological pathways between IQ and RT data, but shared components between mean RT, RT variability and ADHD symptom scores, illustrates key influences in the genetic architecture of the cognitive and energetic processes that underlie the behavioural symptoms of ADHD. In addition, the multivariate genetic model fitting findings provide valuable information for future molecular genetic analyses.

Motion sensor devices such as actigraphs are increasingly used in studies that seek to obtain an objective assessment of activity level. They have many advantages, and are useful additions to research in fields such as sleep assessment, drug efficacy, behavior genetics, and obesity. However, questions still remain over the reliability of data collected using actigraphic assessment. We aimed to apply generalizability theory to actigraph data collected on a large, general-population sample in middle childhood, during 8 cognitive tasks across two body loci, and to examine reliability coefficients on actigraph data aggregated across different numbers of tasks and different numbers of attachment loci. Our analyses show that aggregation greatly increases actigraph data reliability, with reliability coefficients on data collected at one body locus during 1 task (.29) being much lower than that aggregated across data collected on two body loci and during 8 tasks (.66). Further increases in reliability coefficients by aggregating across four loci and 12 tasks were estimated to be modest in prospective analyses, indicating an optimum trade-off between data collection and reliability estimates. We also examined possible instrumental effects on actigraph data and found these to be nonsignificant, further supporting the reliability and validity of actigraph data as a method of activity level assessment.

Background: Activity level is an important component of children’s temperament, as well as being part of the core symptom domain of hyperactivity-impulsivity within attention deficit hyperactivity disorder (ADHD). Yet it is poorly understood, due partly to limitations on parent and teacher ratings, which are typically used as measurements of these symptoms. Methods: We aimed to study the etiology of objectively-measured activity level across two situations, using actigraphs. A population-based sample of 463 7–9-year-old twin pairs were assessed individually both when apart undergoing laboratory-based cognitive testing and when together during a break in testing. Results: Heritability of activity level was estimated as 24% during the test session and at 30% during the break in testing. Shared environmental influences accounted for 27% of the variance in activity level during the test session and 42% of activity level measured during the break. A genetic correlation of 1.0 indicated that the same genes influenced activity level across the two situations, justifying the use of a composite measure of the two situations. This produced a heritability estimate of 36%. Conclusions: Objectively-measured activity level shows a moderate degree of genetic influence, with a common set of genes influencing activity level across situations. This supports the use of actigraphs as an additional source of information in studies that aim to improve phenotype definition for molecular genetic studies of activity level and ADHD. Keywords: Activity level, actigraph, etiology, heritability, twin study, genetic effects, attention deficit hyperactivity disorder. Abbreviations: ADHD: attention deficit hyperactivity disorder; CI: confidence interval; MZ: monozygotic; DZ: dizygotic; A: variance due to additive genetic effects; C: variance due to shared environmental effects; E: variance due to child-specific environmental effects; rA: genetic correlation; rC: shared environment correlation; rE: child-specific environment correlation.

Twin studies using both clinical and population-based samples suggest that the frequent co-occurrence of attention deficit hyperactivity disorder (ADHD) and reading ability/disability (RD) is largely driven by shared genetic influences. While both disorders are associated with lower IQ, recent twin data suggest that the shared genetic variability between reading difficulties and ADHD inattention symptoms is largely independent from genetic influences contributing to general cognitive ability. The current study aimed to extend the previous findings that were based on rating scale measures in a population sample by examining the generalisability of the findings to a clinical population, and by measuring reading difficulties both with a rating scale and with an objective task. This study investigated the familial relationships between ADHD, reading difficulties and IQ in a sample of individuals diagnosed with ADHD combined type, their siblings and control sibling pairs.Multivariate familial models were run on data from 1,789 individuals at ages 6-19. Reading difficulties were measured with both rating scale and an objective task. IQ was obtained using the Wechsler Intelligence Scales (WISC-III/WAIS-III).Significant phenotypic (.2-.4) and familial (.3-.5) correlations were observed among ADHD, reading difficulties and IQ. Yet, 53%-72% of the overlapping familial influences between ADHD and reading difficulties were not shared with IQ.Our finding that familial influences shared with general cognitive ability, although present, do not account for the majority of the overlapping familial influences on ADHD and reading difficulties extends previous findings from a population-based study to a clinically ascertained sample with combined type ADHD.