Losing sleep influences dietary intake in children: a longitudinal compositional analysis of a randomised crossover trial.

BACKGROUND: Although inadequate sleep increases the risk of obesity in children, the mechanisms remain unclear. The aims of this study were to assess how sleep loss influenced dietary intake in children while accounting for corresponding changes in sedentary time and physical activity; and to investigate how changes in time use related to dietary intake. METHODS: A randomized crossover trial in 105 healthy children (8-12 years) with normal sleep (~ 8-11 h/night) compared sleep extension (asked to turn lights off one hour earlier than usual for one week) and sleep restriction (turn lights off one hour later) conditions, separated by a washout week. 24-h time-use behaviors (sleep, wake after sleep onset, physical activity, sedentary time) were assessed using waist-worn actigraphy and dietary intake using two multiple-pass diet recalls during each intervention week. Longitudinal compositional analysis was undertaken with mixed effects regression models using isometric log ratios of time use variables as exposures and dietary variables as outcomes, and participant as a random effect. RESULTS: Eighty three children (10.2 years, 53% female, 62% healthy weight) had 47.9 (SD 30.1) minutes less sleep during the restriction week but were also awake for 8.5 (21.4) minutes less at night. They spent this extra time awake in the day being more sedentary (+ 31 min) and more active (+ 21 min light physical activity, + 4 min MVPA). After adjusting for all changes in 24-h time use, losing 48 min of sleep was associated with consuming significantly more energy (262 kJ, 95% CI:55,470), all of which was from non-core foods (314 kJ; 43, 638). Increases in sedentary time were related to increased energy intake from non-core foods (177 kJ; 25, 329) whereas increases in MVPA were associated with higher intake from core foods (72 kJ; 7,136). Changes in diet were greater in female participants. CONCLUSION: Loss of sleep was associated with increased energy intake, especially of non-core foods, independent of changes in sedentary time and physical activity. Interventions focusing on improving sleep may be beneficial for improving dietary intake and weight status in children. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ANZCTR ACTRN12618001671257, Registered 10th Oct 2018, https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=367587&isReview=true.

Identifying Risk Factors for Presarcopenia in Early Middle Age.

OBJECTIVE: This study aimed to determine whether risk factors for presarcopenia can be identified in a sample of early middle-aged men and women. DESIGN: Prospective study. SETTING: Longitudinal data from the Dunedin Multidisciplinary Health and Development Study were used to investigate the relationship between presarcopenia at age 45 years and selected early markers at ages 26, 32, and 38 years. PARTICIPANTS: Longitudinal data from N=899 participants from the Dunedin Multidisciplinary Health and Development Study. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Presarcopenia was defined as low relative appendicular lean mass index assessed by dual energy x-ray absorptiometry and low strength assessed by grip strength. Logistic regressions were used to describe the association between selected markers and presarcopenia at age 45 years. RESULTS: Multivariate logistic regression revealed that a higher body mass index (BMI) at ages 26, 32, and 38 years was associated with lower likelihood of presarcopenia at age 45 years in both men and women (odds ratio [OR] range, 0.46-0.64). Higher age-normative grip strength at age 38 years in both men and women (OR range, 0.88-0.92) was also associated with lower likelihood for presarcopenia. Lastly, lower self-perceived physical fitness level in men at age 38 years was associated with an increased likelihood of presarcopenia at age 45 years (OR, 9.35; 95% confidence interval, 3.28-26.70). CONCLUSIONS: BMI and strength were associated with lower likelihood of presarcopenia during middle age. A higher likelihood of presarcopenia was associated with sex-specific lower self-perceived physical fitness. These modifiable biomarkers may serve as targets for clinical screening and early intervention aimed at slowing or preventing progression to sarcopenia in old age.

The protective roles of affectionate behaviors and communication on mental quality of life of couples living with fibromyalgia: movement toward a dyadic perspective.

This study assessed the impact of affectionate behaviors and communication problems on the mental quality of life (mQoL) in couples with fibromyalgia. Dyadic multilevel modeling in 204 fibromyalgia couples found that people with fibromyalgia (PwFM) who engaged in high levels of affectionate behaviors with their partner had improved mQoL. There was no significant association between affectionate behaviors and mQoL for their partners. Similarly, when PwFM and their partners had more communication problems within the couple, they had poor mQoL. Both models found that higher levels of pain interference for PwFM were significantly associated with poorer mQoL for both members of the couple. Young partners were significantly more likely to report poorer mQoL. Findings highlight the importance of the interpersonal context of fibromyalgia and the protective roles that affectionate behaviors and positive communication can play. Clinicians should include the partner in the care plan and treat the couple as one unit to better optimize the health of both members.

Reject the "Practice Readiness Myth": Ask if systems are ready for nursing graduates instead.

The nursing profession is engaged in robust national dialogue on how to implement competency-based education. This dialogue often conflates the concept of "competency-based education" with nursing "competence" or "practice readiness." Our aim is to discuss the potential harms of conflating "competency-based education" with "competence" or "practice readiness." This commentary explores the possible risks of issue conflation. Risks include (a) suggesting that nurses who have successfully obtained licensure are not "competent" or "ready to practice," and (b) de-emphasizing the importance of safe and sustainable work environments for new graduate nurses. We discuss the need to separate conversations about "competency-based education" and "practice readiness"; the need to increase the clarity and specificity of discourse surrounding competency-based education; and the need for strategic alignment across academia and practice.

Results from Aotearoa New Zealand's 2022 Report Card on Physical Activity for Children and Youth: A call to address inequities in health-promoting activities.

Background: This article reports the methods and findings for Aotearoa New Zealand's 2022 Report Card on Physical Activity for Children and Youth indicators, and on inequities within these indicators. Methods: Grades were assigned to indicators using the Active Healthy Kids Global Alliance criteria depending on data availability, and inequities reported based on gender, ethnicity, disability status, area-level socioeconomic deprivation, urbanicity, and school year. Two additional indicators were included in this report card: Sleep, and Physical literacy. Results: Grades were assigned to indicators as follows: Overall physical activity: C+, Organised sport and physical activity: B-, Physical literacy: B, Active transportation: D, Sedentary behaviours: C-, Sleep: B+, Whanau (family) and peers: D, School: C+, Government: A. Inequities across all socio-demographic variables were observed. An 'inconclusive' grade was assigned to the Active play, Physical fitness, and Community and Environment indicators due to insufficient data. Conclusion: It is imperative that targeted, comprehensive, and population-specific approaches are implemented to support health-promoting physical activity behaviours and reduce inequities among children and youth in Aotearoa. There is a need to promote all dimensions of physical activity (overall activity, active play, recreation, organised sport, active transportation) and the reduction of screen time through policy, research, evidence-based social marketing campaigns, and urban design. Regular, nationally representative surveys that enable the consistent and regular measurement of key Report Card indicators are needed.

Targeting DNA Damage Response and Replication Stress in Pancreatic Cancer.

BACKGROUND & AIMS: Continuing recalcitrance to therapy cements pancreatic cancer (PC) as the most lethal malignancy, which is set to become the second leading cause of cancer death in our society. The study aim was to investigate the association between DNA damage response (DDR), replication stress, and novel therapeutic response in PC to develop a biomarker-driven therapeutic strategy targeting DDR and replication stress in PC. METHODS: We interrogated the transcriptome, genome, proteome, and functional characteristics of 61 novel PC patient-derived cell lines to define novel therapeutic strategies targeting DDR and replication stress. Validation was done in patient-derived xenografts and human PC organoids. RESULTS: Patient-derived cell lines faithfully recapitulate the epithelial component of pancreatic tumors, including previously described molecular subtypes. Biomarkers of DDR deficiency, including a novel signature of homologous recombination deficiency, cosegregates with response to platinum (P < .001) and PARP inhibitor therapy (P < .001) in vitro and in vivo. We generated a novel signature of replication stress that predicts response to ATR (P < .018) and WEE1 inhibitor (P < .029) treatment in both cell lines and human PC organoids. Replication stress was enriched in the squamous subtype of PC (P < .001) but was not associated with DDR deficiency. CONCLUSIONS: Replication stress and DDR deficiency are independent of each other, creating opportunities for therapy in DDR-proficient PC and after platinum therapy.

Australian guidelines for the prevention and treatment of posttraumatic stress disorder: Updates in the third edition.

OBJECTIVE: This paper describes the development of the third edition of the National Health and Medical Research Australian Guidelines for the Prevention and Treatment of Acute Stress Disorder, posttraumatic stress disorder and Complex posttraumatic stress disorder, highlighting key changes in scope, methodology, format and treatment recommendations from the previous 2013 edition of the Guidelines. METHOD: Systematic review of the international research was undertaken, with GRADE methodology used to assess the certainty of the evidence, and evidence to decision frameworks used to generate recommendations. The Guidelines are presented in an online format using MAGICApp. RESULTS: Key changes since the publication of the 2013 Guidelines include a new conditional recommendation for Child and Family Traumatic Stress Intervention for children and adolescents with symptoms within the first 3 months of trauma, and a strong recommendation for trauma-focused cognitive behaviour therapy for the child alone or with a caregiver, for those with diagnosed posttraumatic stress disorder. For adults with posttraumatic stress disorder, strong recommendations are made for specific types of trauma-focused cognitive behaviour therapy and conditional recommendations are made for five additional psychological interventions. Where medication is indicated for adults with posttraumatic stress disorder, venlafaxine is now conditionally recommended alongside sertraline, paroxetine or fluoxetine. CONCLUSION: These Guidelines, based on systematic review of the international literature, are intended to guide decision making for practitioners, service planners, funders and those seeking treatment for trauma related mental health concerns. For an Australian Guideline, a critical limitation is the absence of research on the treatment of Australian Aboriginal and Torres Strait Islander peoples. The new online format of the Australian posttraumatic stress disorder Guidelines means that they can be updated as sufficient new evidence becomes available.

Chronic Pain Clinical and Prescriptive Practices in the Cannabis Era.

BACKGROUND: To explore how health care providers in the United States are adapting clinical recommendations and prescriptive practices in response to patient use of medical cannabis (MC) for chronic pain symptoms. DESIGN: Literature searches queried MeSH/Subject terms "chronic pain," "clinician," "cannabis," and Boolean text words "practice" and "analgesics" in EBSCOHost, EMBASE, PubMed, and Scopus, published 2010-2021 in the United States. Twenty-one primary, peer-reviewed studies met criteria. METHODS: Studies are synthesized under major headings: recommending MC for chronic pain; MC and prescription opioids; and harm reduction of MC. RESULTS: MC is increasingly utilized by patients for chronic pain symptoms. Clinical recommendations for or against MC are influenced by scopes of practice, state or federal laws, institutional policies, education, potential patient harm (or indirect harm of others), and perceived confidence. Epidemiologic and cohort studies show downward trajectories of opioid prescribing and consumption in states with legal cannabis. However, clinicians' recommendations and prescription practices are nonuniform. Impacts of cannabis laws are clear between nongovernmental and governmental institutions. Strategies addressing MC and opioid use include frequent visits, and, to reduce harm, suggesting alternative therapies and treating substance use disorders. CONCLUSIONS: MC use for chronic pain is increasing with cannabis legalization. Provider practices are heterogenous, demonstrating a balance of treating chronic pain using available evidence, while being aware of potential harms associated with MC and opioids.

Age- and sex-specific visceral fat reference cutoffs and their association with cardio-metabolic risk.

BACKGROUND: Although excess visceral fat (VAT) is associated with numerous cardio-metabolic risk factors, measurement of this fat depot has historically been difficult. Recent dual X-ray absorptiometry approaches have provided an accessible estimate of VAT that has shown acceptable validity against gold standard methods. The aims of this study were to (i) evaluate DXA measured VAT as a predictor of elevated blood lipids and blood pressure and (ii) calculate thresholds associated with these cardio-metabolic risk factors. SUBJECTS/METHODS: The sample comprised 1482 adults (56.4% women) aged 18-66 years. Total body scans were performed using a GE Lunar Prodigy, and VAT analyses were enabled through Corescan software (v 16.0). Blood pressure and blood lipids were measured by standard procedures. Regression models assessed how VAT mass was associated with each cardio-metabolic risk factor compared to other body composition measures. Measures of sensitivity and specificity were used to determine age- and sex-specific cut points for VAT mass associated with high cardio-metabolic risk. RESULTS: Similar to waist circumference, VAT mass was a strong predictor of cardio-metabolic risk especially in men over age 40. Four cut-offs for VAT mass were proposed, above which the cardio-metabolic risk increased: 700 g in women <40 yrs; 800 g in women 40+ yrs; 1000g in men <40 yrs; and 1200 g in men 40+ yrs. In general, these cut-offs discriminated well between those with high and low cardio-metabolic risk. CONCLUSIONS: In both sexes, DXA measured VAT was associated with traditional cardio-metabolic risk factors, particularly high blood pressure in those 40+ yrs and low HDL < 40 yrs. These reference values provide a simple, accessible method to assess cardio-metabolic risk in adults.

Adherence to 24-h movement behavior guidelines and psychosocial functioning in young children: a longitudinal analysis.

BACKGROUND: A recent paradigm shift has highlighted the importance of considering how sleep, physical activity and sedentary behaviour work together to influence health, rather than examining each behaviour individually. We aimed to determine how adherence to 24-h movement behavior guidelines from infancy to the preschool years influences mental health and self-regulation at 5 years of age. METHODS: Twenty-four hour movement behaviors were measured by 7-day actigraphy (physical activity, sleep) or questionnaires (screen time) in 528 children at 1, 2, 3.5, and 5 years of age and compared to mental health (anxiety, depression), adaptive skills (resilience), self-regulation (attentional problems, hyperactivity, emotional self-control, executive functioning), and inhibitory control (Statue, Head-Toes-Knees-Shoulders task) outcomes at 5 years of age. Adjusted standardised mean differences (95% CI) were determined between those who did and did not achieve guidelines at each age. RESULTS: Children who met physical activity guidelines at 1 year of age (38.7%) had lower depression (mean difference [MD]: -0.28; 95% CI: -0.51, -0.06) and anxiety (MD: -0.23; 95% CI: -0.47, 0.00) scores than those who did not. At the same age, sleeping for 11-14 h or having consistent wake and sleep times was associated with lower anxiety (MD: -0.34; 95% CI: -0.66, -0.02) and higher resilience (MD: 0.35; 95% CI: 0.03, 0.68) scores respectively. No significant relationships were observed at any other age or for any measure of self-regulation. Children who consistently met screen time guidelines had lower anxiety (MD: -0.43; 95% CI: -0.68, -0.18) and depression (MD: -0.36; 95% CI: -0.62, -0.09) scores at 5. However, few significant relationships were observed for adherence to all three guidelines; anxiety scores were lower (MD: -0.42; 95% CI: -0.72, -0.12) in the 20.2% who adhered at 1 year of age, and depression scores were lower (MD: -0.25; 95% CI: -0.48, -0.02) in the 36.7% who adhered at 5 years of age compared with children who did not meet all three guidelines. CONCLUSIONS: Although adherence to some individual movement guidelines at certain ages throughout early childhood was associated with improved mental health and wellbeing at 5 years of age, particularly reduced anxiety and depression scores, there was little consistency in these relationships. Future work should consider a compositional approach to 24-h time use and how it may influence mental wellbeing. TRIAL REGISTRATION: ClinicalTrials.gov number NCT00892983.

Measuring short-term eating behaviour and desire to eat: Validation of the child eating behaviour questionnaire and a computerized 'desire to eat' computerized questionnaire.

The Child Eating Behaviour Questionnaire (CEBQ) is designed to measure 'usual' eating behaviour, with no time period attached, thus may not be suitable for assessing the effectiveness of short-term experimental studies. The aim of this study was to validate i) the CEBQ adapted to measure 'past week' rather than 'usual' eating behaviour, and ii) a computerized questionnaire assessing desire to eat core and non-core foods, against an objective measure of eating behaviour and food intake (eating in the absence of hunger (EAH) experiment). Children (n = 103) aged 8-12 years completed the desire to eat questionnaire followed by the EAH experiment while primary caregivers completed the adapted CEBQ. Results from the CEBQ showed that children with greater 'satiety responsiveness' (1-point higher) consumed less energy (-342 kJ; 95% CI -574, -110) whereas those with greater 'enjoyment of food' scale consumed more energy (380 kJ; 95% CI 124, 636) during the ad-libitum phase of the EAH experiment. Higher scores for slowness in eating (-705 kJ; 95% CI -1157, -254), emotional undereating (-590 kJ; 95% CI -1074, -106) and food fussiness (-629 kJ; 95% CI -1103, -155) were associated with lower total energy intake. Children who expressed greater desire to eat non-core foods consumed more energy in total (275 kJ; 95% CI 87, 463). Overall, this adapted CEBQ appears valid for measuring several short-term eating behaviours in children. The desire to eat questionnaire may be useful for identifying short-term susceptibility to overeating, however further investigation into how ratings of desire relate to the intake of highly palatable, energy dense foods is warranted.

Nutrients and solids removal in bioretention columns using recycled materials under intermittent and frequent flow operations.

This research investigated the fate and removal of nitrite (NO2-N), nitrate (NO3-N), orthophosphate (PO4-P), and total suspended solids (TSS) in two bioretention columns, which were designed with three recycled materials. The first column was packed with Recycled Concrete Aggregate (RCA). The second column was a Layered Media (LM), which has layers of RCA with crushed glass and rice husks. The columns were tested under intermittent and frequent operations of synthetic runoff with low and high feed concentrations. The effect of inflow concentration, antecedent dry days (ADD), column age, and the anticipated number of events (EN) was also statistically analyzed on the performance of columns. Depending on column types, nutrient removal was significantly (p < 0.05) increased under frequent flow operations by 26-53% over intermittent. However, TSS removal was notably (p < 0.05) increased by 23-35% under intermittent operations over frequent. Overall, LM showed an increased NO2-N (92 ± 2%) and NO3-N (88% ± 2%) removal under low feed frequent operations and TSS removal (97% ± 2%) under initial intermittent operations. On the contrary, RCA showed a maximum of 99% PO4-P removal under high feed frequent operations. Results showed that the nutrient outflow concentration was found to have a negative correlation with EN and column age and a positive correlation with ADDs throughout the experiments.

Precision Oncology in Surgery: Patient Selection for Operable Pancreatic Cancer.

OBJECTIVE: We aimed to define preoperative clinical and molecular characteristics that would allow better patient selection for operative resection. BACKGROUND: Although we use molecular selection methods for systemic targeted therapies, these principles are not applied to surgical oncology. Improving patient selection is of vital importance for the operative treatment of pancreatic cancer (pancreatic ductal adenocarcinoma). Although surgery is the only chance of long-term survival, 80% still succumb to the disease and approximately 30% die within 1 year, often sooner than those that have unresected local disease. METHOD: In 3 independent pancreatic ductal adenocarcinoma cohorts (total participants = 1184) the relationship between aberrant expression of prometastatic proteins S100A2 and S100A4 and survival was assessed. A preoperative nomogram based on clinical variables available before surgery and expression of these proteins was constructed and compared to traditional measures, and a postoperative nomogram. RESULTS: High expression of either S100A2 or S100A4 was independent poor prognostic factors in a training cohort of 518 participants. These results were validated in 2 independent patient cohorts (Glasgow, n = 198; Germany, n = 468). Aberrant biomarker expression stratified the cohorts into 3 distinct prognostic groups. A preoperative nomogram incorporating S100A2 and S100A4 expression predicted survival and nomograms derived using postoperative clinicopathological variables. CONCLUSIONS: Of those patients with a poor preoperative nomogram score, approximately 50% of patients died within a year of resection. Nomograms have the potential to improve selection for surgery and neoadjuvant therapy, avoiding surgery in aggressive disease, and justifying more extensive resections in biologically favorable disease.

Quantity versus quality of objectively measured sleep in relation to body mass index in children: cross-sectional and longitudinal analyses.

BACKGROUND/OBJECTIVES: Although sleep duration is well established as a risk factor for child obesity, how measures of sleep quality relate to body size is less certain. The aim of this study was to determine how objectively measured sleep duration, sleep timing, and sleep quality were related to body mass index (BMI) cross-sectionally and longitudinally in school-aged children. SUBJECTS/METHODS: All measures were obtained at baseline, 12 and 24 months in 823 children (51% female, 53% European, 18% Maori, 12% Pacific, 9% Asian) aged 6-10 years at baseline. Sleep duration, timing, and quality were measured using actigraphy over 7 days, height and weight were measured using standard techniques, and parents completed questionnaires on demographics (baseline only), dietary intake, and television usage. Data were analysed using imputation; mixed models, with random effects for person and age, estimated both a cross-sectional effect and a longitudinal effect on BMI z-score, adjusted for multiple confounders. RESULTS: The estimate of the effect on BMI z-score for each additional hour of sleep was -0.22 (95% CI: -0.33, -0.11) in cross-sectional analyses and -0.05 (-0.10, -0.004) in longitudinal analyses. A greater effect was observed for weekday sleep duration than weekend sleep duration but variability in duration was not related to BMI z-score. While sleep timing (onset or midpoint of sleep) was not related to BMI, children who were awake in the night more frequently (0.19; 0.06, 0.32) or for longer periods (0.18; 0.06, 0.36) had significantly higher BMI z-scores cross-sectionally, but only the estimates for total time awake (minutes) were significant longitudinally (increase in BMI z-score of 0.04 for each additional hour awake). CONCLUSION: The beneficial effect of a longer sleep duration on BMI was consistent in children, whereas evidence for markers of sleep quality and timing were more variable.

Do young children consistently meet 24-h sleep and activity guidelines? A longitudinal analysis using actigraphy.

BACKGROUND: Existing studies examining adherence to 24-h movement guidelines in young children are mostly cross sectional and have not assessed additional guidelines relating to activity intensity or regularity in sleep patterns. The aims of this study were to determine adherence to full sleep, activity, and sedentary behaviour guidelines from 1-5 years of age, whether adherence tracked over time, and how adherence was related to body composition cross sectionally and prospectively. SUBJECTS/METHODS: Data were obtained from 547 children who were participants in a randomised controlled trial. At 1, 2, and 5 years of age, children wore Actical accelerometers 24-h a day for 5-7 days, height and weight were measured, and parents completed questionnaires on screen time and restraint (1 and 2 years only). A dual-energy x-ray absorptiometry (DXA) scan measured body composition at 5 years of age. RESULTS: Although adherence to general sleep and activity guidelines was high, few children had regular sleep patterns. Adherence to all three guidelines ranged from 12.3 to 41.3% at the different ages, although these estimates decreased to 0.6-9.3% when activity intensity (60 min of energetic play) and sleep regularity (consistent sleep and wake times) were included. Children who met all three guidelines at a given age were more likely to meet all three guidelines at a subsequent age (odds ratio, 95% CI: 2.6, 1.04-6.4 at 1 year and 2.5, 1.1-5.9 at 2 years). However, adherence to meeting all three guidelines at earlier ages was not related to BMI z-score or body composition at age 5, either cross sectionally or prospectively. CONCLUSIONS: Strategies to promote adherence to movement guidelines among young children are warranted, particularly to reduce screen time, and encouraging regular sleep patterns.

Efficacy of a compulsory homework programme for increasing physical activity and improving nutrition in children: a cluster randomised controlled trial.

BACKGROUND: Most physical activity interventions in children focus on the school setting; however, children typically engage in more sedentary activities and spend more time eating when at home. The primary aim of this cluster randomised controlled trial was to investigate the effects of a compulsory, health-related homework programme on physical activity, dietary patterns, and body size in primary school-aged children. METHODS: A total of 675 children aged 7-10 years from 16 New Zealand primary schools participated in the Healthy Homework study. Schools were randomised into intervention and control groups (1:1 allocation). Intervention schools implemented an 8-week applied homework and in-class teaching module designed to increase physical activity and improve dietary patterns. Physical activity was the primary outcome measure, and was assessed using two sealed pedometers that monitored school- and home-based activity separately. Secondary outcome measures included screen-based sedentary time and selected dietary patterns assessed via parental proxy questionnaire. In addition, height, weight, and waist circumference were measured to obtain body mass index (BMI) and waist-to-height ratio (WHtR). All measurements were taken at baseline (T0), immediately post-intervention (T1), and 6-months post-intervention (T2). Changes in outcome measures over time were estimated using generalised linear mixed models (GLMMs) that adjusted for fixed (group, age, sex, group x time) and random (subjects nested within schools) effects. Intervention effects were also quantified using GLMMs adjusted for baseline values. RESULTS: Significant intervention effects were observed for weekday physical activity at home (T1 [P < 0.001] and T2 [P = 0.019]), weekend physical activity (T1 [P < 0.001] and T2 [P < 0.001]), BMI (T2 only [P = 0.020]) and fruit consumption (T1 only [P = 0.036]). Additional analyses revealed that the greatest improvements in physical activity occurred in children from the most socioeconomically deprived schools. No consistent effects on sedentary time, WHtR, or other dietary patterns were observed. CONCLUSIONS: A compulsory health-related homework programme resulted in substantial and consistent increases in children's physical activity - particularly outside of school and on weekends - with limited effects on body size and fruit consumption. Overall, our findings support the integration of compulsory home-focused strategies for improving health behaviours into primary education curricula. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry, ACTRN12618000590268 . Registered 17 April 2018.

The effect of mild sleep deprivation on diet and eating behaviour in children: protocol for the Daily Rest, Eating, and Activity Monitoring (DREAM) randomized cross-over trial.

BACKGROUND: Although insufficient sleep has emerged as a strong, independent risk factor for obesity in children, the mechanisms by which insufficient sleep leads to weight gain are uncertain. Observational research suggests that being tired influences what children eat more than how active they are, but only experimental research can determine causality. Few experimental studies have been undertaken to determine how reductions in sleep duration might affect indices of energy balance in children including food choice, appetite regulation, and sedentary time. The primary aim of this study is to objectively determine whether mild sleep deprivation increases energy intake in the absence of hunger. METHODS: The Daily, Rest, Eating, and Activity Monitoring (DREAM) study is a randomized controlled trial investigating how mild sleep deprivation influences eating behaviour and activity patterns in children using a counterbalanced, cross-over design. One hundred and ten children aged 8-12 years, with normal reported sleep duration of 8-11 h per night will undergo 2 weeks of sleep manipulation; seven nights of sleep restriction by going to bed 1 hr later than usual, and seven nights of sleep extension going to bed 1 hr earlier than usual, separated by a washout week. During each experimental week, 24-h movement behaviours (sleep, physical activity, sedentary behaviour) will be measured via actigraphy; dietary intake and context of eating by multiple 24-h recalls and wearable camera images; and eating behaviours via objective and subjective methods. At the end of each experimental week a feeding experiment will determine energy intake from eating in the absence of hunger. Differences between sleep conditions will be determined to estimate the effects of reducing sleep duration by 1-2 h per night. DISCUSSION: Determining how insufficient sleep predisposes children to weight gain should provide much-needed information for improving interventions for the effective prevention of obesity, thereby decreasing long-term morbidity and healthcare burden. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12618001671257 . Registered 10 October 2018.

Physical activity and inactivity trajectories associated with body composition in pre-schoolers.

BACKGROUND/OBJECTIVES: Early childhood is characterised by rapid development and is a critical period for the establishment of activity behaviours. We aim to examine how physical activity (PA) and sedentary behaviour (SB) track during the first 5 years of life, and to investigate associations between trajectories and body composition at 5 years of age. SUBJECTS/METHODS: A total of 438 participants (50% male) wore an Actical accelerometer for 5 days at at least two of 1, 2, 3.5 and 5 years of age. Spearman correlation coefficients examined PA tracking from age 1 to 5 and trajectories of PA and SB were estimated using discrete mixture modelling. Regression models tested associations between both PA and SB trajectories and body composition measures. RESULTS: Tracking coefficients for PA ranged from r = 0.31-0.51 across the ages, with similar tracking observed for sedentary behaviour (r = 0.21-0.39). Four distinct trajectory patterns were identified separately for PA and SB: consistently low, consistently high, increasing and decreasing. BMI and waist circumference were not significantly associated with PA trajectories, but those in the consistently high activity group had significantly lower % body fat (95% CI) at age 5 (14.3%; 13.5, 15.2) than those in the consistently low (16.8%; 15.6, 18.2) or increasing (15.7%; 14.7, 16.7) groups (P = 0.017). Sedentary behaviour trajectories were not associated with any of the anthropometric measures at age 5 (P > 0.05). CONCLUSIONS: Physical activity and sedentary behaviour tracking is broadly similar from infancy to early childhood. Children with consistently higher levels of physical activity have reduced body fat at 5 years of age, although differences are relatively small.

Sleep timing is associated with diet and physical activity levels in 9-11-year-old children from Dunedin, New Zealand: the PEDALS study.

It is well documented that short sleep duration is associated with excess body weight and poor food intake in children. It has been suggested that sleep timing behaviour may also be an important predictor of weight and other related behaviours, independent of sleep duration; however, there is a lack of research investigating these relationships. The present study investigated sleep timing in association with diet and physical activity levels in 439 children aged 9-11 years old from New Zealand. Sleep and physical activity data were collected using accelerometry, and food choice using a short food-frequency questionnaire. Participants were classified into one of four sleep timing behaviour categories using the median split for sleep-onset and -offset times. Differences between sleep timing groups for weekly consumption frequency of selected food groups, dietary pattern scores and minutes of moderate-to-vigorous physical activity were examined. Children in the late sleep/late wake category had a lower 'Fruit & Vegetables' pattern score [mean difference (95% CI): -0.3 (-0.5, -0.1)], a lower consumption frequency of fruit and vegetables [mean weekly difference (95% CI): -2.9 (-4.9, -0.9)] and a higher consumption frequency of sweetened beverages [mean weekly difference (95% CI): 1.8 (0.2, 3.3)] compared with those in the early sleep/early wake category. Additionally, children in the late sleep/late wake category accumulated fewer minutes of moderate-to-vigorous physical activity per day compared with those in the early sleep/early wake category [mean difference (95% CI): -9.4 (-15.3, -3.5)]. These findings indicate that sleep timing, even after controlling for sleep duration, was associated with both food consumption and physical activity.

24-h movement behaviors from infancy to preschool: cross-sectional and longitudinal relationships with body composition and bone health.

BACKGROUND: New physical activity guidelines for children address all movement behaviors across the 24-h day (physical activity, sedentary behavior, sleep), but how each component relates to body composition when adjusted for the compositional nature of 24-h data is uncertain. AIMS: To i) describe 24-h movement behaviors from 1 to 5 years of age, ii) determine cross-sectional relationships with body mass index (BMI) z-score, iii) determine whether movement behaviors from 1 to 5 years of age predict body composition and bone health at 5 years. METHODS: 24-h accelerometry data were collected in 380 children over 5-7 days at 1, 2, 3.5 and 5 years of age to determine the proportion of the day spent: sedentary (including wake after sleep onset), in light (LPA) and moderate-to-vigorous physical activity (MVPA), and asleep (including naps). BMI was determined at each age and a dual-energy x-ray absorptiometry (DXA) scan measured fat mass, bone mineral content (BMC) and bone mineral density (BMD) at 5 years of age. 24-h movement data were transformed into isometric log-ratio co-ordinates for multivariable regression analysis and effect sizes back-transformed. RESULTS: At age 1, children spent 49.6% of the 24-h day asleep, 38.2% sedentary, 12.1% in LPA, and 0.1% in MVPA, with corresponding figures of 44.4, 33.8, 19.8 and 1.9% at 5 years of age. Compositional time use was only related significantly to BMI z-score at 3.5 years in cross-sectional analyses. A 10% increase in mean sleep time (65 min) was associated with a lower BMI z-score (estimated difference, - 0.25; 95% CI, - 0.42 to - 0.08), whereas greater time spent sedentary (10%, 47 min) or in LPA (10%, 29 min) were associated with higher BMI z-scores (0.12 and 0.08 respectively, both p < 0.05). Compositional time use from 1 to 3.5 years was not related to future BMI z-score or percent fat. Although MVPA at 2 and 3.5 years was consistently associated with higher BMD and BMC at 5 years, actual differences were small. CONCLUSIONS: Considerable changes in compositional time use occur from 1 to 5 years of age, but there is little association with adiposity. Although early MVPA predicted better bone health, the differences observed had little clinical relevance. TRIAL REGISTRATION: ClinicalTrials.gov number NCT00892983 .