Appraisal of Australian and New Zealand paediatric sepsis guidelines

OBJECTIVE

Clinical practice guidelines (CPGs) are an important tool for the management of children with sepsis. The quality, consistency and concordance of Australian and New Zealand (ANZ) childhood sepsis CPGs with the Australian Commission on Safety and Quality in Healthcare (ACSQHC) sepsis clinical care standards and international sepsis guidelines is unclear.

METHODS

We accessed childhood sepsis CPGs for all ANZ states and territories through Paediatric Research in Emergency Departments International Collaborative members. The guidelines were assessed for quality using the AGREE-II instrument. Consistency between CPG treatment recommendations was assessed, as was concordance with the ACSQHC sepsis clinical care standards and international sepsis guidelines.

RESULTS

Overall, eight CPGs were identified and assessed. CPGs used a narrative and pathway format, with those using both having the highest quality overall. CPG quality was highest for description of scope and clarity of presentation, and lowest for editorial independence. Consistency between guidelines for initial treatment recommendations was poor, with substantial variation in the choice and urgency of empiric antimicrobial administration; the choice, volume and urgency of fluid resuscitation; and the choice of first-line vasoactive agent. Most CPGs were concordant with time-critical components of the ACSQHC sepsis clinical care standard, although few addressed post-acute care. Concordance with international sepsis guidelines was poor.

CONCLUSION

Childhood sepsis CPGs in current use in ANZ are of variable quality and lack consistency with key treatment recommendations. CPGs are concordant with the ACSQHC care standard, but not with international sepsis guidelines. A bi-national sepsis CPG may reduce unnecessary variation in care.

The effect of maternal position on placental blood flow and fetoplacental oxygenation in late gestation fetal growth restriction: a magnetic resonance imaging study

Fetal growth restriction (FGR) and maternal supine going-to-sleep position are both risk factors for late stillbirth. This study aimed to use magnetic resonance imaging (MRI) to quantify the effect of maternal supine position on maternal-placental and fetoplacental blood flow, placental oxygen transfer and fetal oxygenation in FGR and healthy pregnancies. Twelve women with FGR and 27 women with healthy pregnancies at 34-38 weeks' gestation underwent MRI in both left lateral and supine positions. Phase-contrast MRI and a functional MRI technique (DECIDE) were used to measure blood flow in the maternal internal iliac arteries (IIAs) and umbilical vein (UV), placental oxygen transfer (placental flux), fetal oxygen saturation (FO2 ), and fetal oxygen delivery (delivery flux). The presence of FGR, compared to healthy pregnancies, was associated with a 7.8% lower FO2 (P = 0.02), reduced placental flux, and reduced delivery flux. Maternal supine positioning caused a 3.8% reduction in FO2 (P = 0.001), and significant reductions in total IIA flow, placental flux, UV flow and delivery flux compared to maternal left lateral position. The effect of maternal supine position on fetal oxygen delivery was independent of FGR pregnancy, meaning that supine positioning has an additive effect of reducing fetal oxygenation further in women with FGR, compared to women with appropriately grown for age pregnancies. Meanwhile, the effect of maternal supine positioning on placental oxygen transfer was not independent of the effect of FGR. Therefore, growth-restricted fetuses, which are chronically hypoxaemic, experience a relatively greater decline in oxygen transfer when mothers lie supine in late gestation compared to appropriately growing fetuses. KEY POINTS: Fetal growth restriction (FGR) is the most common risk factor associated with stillbirth, and early recognition and timely delivery is vital to reduce this risk. Maternal supine going-to-sleep position is found to increase the risk of late stillbirth but when combined with having a FGR pregnancy, maternal supine position leads to 15 times greater odds of stillbirth compared to supine sleeping with appropriately grown for age (AGA) pregnancies. Using MRI, this study quantifies the chronic hypoxaemia experienced by growth-restricted fetuses due to 13.5% lower placental oxygen transfer and 26% lower fetal oxygen delivery compared to AGA fetuses. With maternal supine positioning, there is a 23% reduction in maternal-placental blood flow and a further 14% reduction in fetal oxygen delivery for both FGR and AGA pregnancies, but this effect is proportionally greater for growth-restricted fetuses. This knowledge emphasises the importance of avoiding supine positioning in late pregnancy, particularly for vulnerable FGR pregnancies.

Core outcomes and factors influencing the experience of care for children with severe acute exacerbations of asthma: a qualitative study

OBJECTIVE

To identify the outcomes considered important, and factors influencing the patient experience, for parents and caregivers of children presenting to hospital with a severe acute exacerbation of asthma. This work contributes to the outcome-identification process in developing a core outcome set (COS) for future clinical trials in children with severe acute asthma.

DESIGN

A qualitative study involving semistructured interviews with parents and caregivers of children who presented to hospital with a severe acute exacerbation of asthma.

SETTING

Hospitals in 12 countries associated with the global Pediatric Emergency Research Networks, including high-income and middle-income countries. Interviews were conducted face-to-face, by teleconference/video-call, or by phone.

FINDINGS

Overall, there were 54 interviews with parents and caregivers; 2 interviews also involved the child. Hospital length of stay, intensive care unit or high-dependency unit (HDU) admission, and treatment costs were highlighted as important outcomes influencing the patient and family experience. Other potential clinical trial outcomes included work of breathing, speed of recovery and side effects. In addition, the patient and family experience was impacted by decision-making leading up to seeking hospital care, transit to hospital, waiting times and the use of intravenous treatment. Satisfaction of care was related to communication with clinicians and frequent reassessment.

CONCLUSIONS

This study provides insight into the outcomes that parents and caregivers believe to be the most important to be considered in the process of developing a COS for the treatment of acute severe exacerbations of asthma.

Impact of SARS-CoV-2 Infection on the Association Between Laboratory Tests and Severe Outcomes Among Hospitalized Children

Background

To assist clinicians with identifying children at risk of severe outcomes, we assessed the association between laboratory findings and severe outcomes among severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected children and determined if SARS-CoV-2 test result status modified the associations.

Methods

We conducted a cross-sectional analysis of participants tested for SARS-CoV-2 infection in 41 pediatric emergency departments in 10 countries. Participants were hospitalized, had laboratory testing performed, and completed 14-day follow-up. The primary objective was to assess the associations between laboratory findings and severe outcomes. The secondary objective was to determine if the SARS-CoV-2 test result modified the associations.

Results

We included 1817 participants; 522 (28.7%) SARS-CoV-2 test-positive and 1295 (71.3%) test-negative. Seventy-five (14.4%) test-positive and 174 (13.4%) test-negative children experienced severe outcomes. In regression analysis, we found that among SARS-CoV-2-positive children, procalcitonin ≥0.5 ng/mL (adjusted odds ratio [aOR], 9.14; 95% CI, 2.90-28.80), ferritin >500 ng/mL (aOR, 7.95; 95% CI, 1.89-33.44), D-dimer ≥1500 ng/mL (aOR, 4.57; 95% CI, 1.12-18.68), serum glucose ≥120 mg/dL (aOR, 2.01; 95% CI, 1.06-3.81), lymphocyte count <1.0 × 109/L (aOR, 3.21; 95% CI, 1.34-7.69), and platelet count <150 × 109/L (aOR, 2.82; 95% CI, 1.31-6.07) were associated with severe outcomes. Evaluation of the interaction term revealed that a positive SARS-CoV-2 result increased the associations with severe outcomes for elevated procalcitonin, C-reactive protein (CRP), D-dimer, and for reduced lymphocyte and platelet counts.

Conclusions

Specific laboratory parameters are associated with severe outcomes in SARS-CoV-2-infected children, and elevated serum procalcitonin, CRP, and D-dimer and low absolute lymphocyte and platelet counts were more strongly associated with severe outcomes in children testing positive compared with those testing negative.

Acute paediatric asthma treatment in the prehospital setting: a retrospective observational study

OBJECTIVES

To describe the incidence of and patterns of 'escalated care' (care in addition to standard treatment with systemic corticosteroids and inhaled bronchodilators) for children receiving prehospital treatment for asthma.

DESIGN

Retrospective observational study.

SETTING

State-wide ambulance service data (Ambulance Victoria in Victoria, Australia, population 6.5 million) PARTICIPANTS: Children aged 1-17 years and given a final diagnosis of asthma by the treating paramedics and/or treated with inhaled bronchodilators from 1 July 2019 to 30 June 2020.

PRIMARY AND SECONDARY OUTCOME MEASURES

We classified 'escalation of care' as parenteral administration of epinephrine, or provision of respiratory support. We compared clinical, demographic and treatments administered between those receiving and not receiving escalation of care.

RESULTS

Paramedics attended 1572 children with acute exacerbations of asthma during the 1 year study period. Of these, 22 (1.4%) had escalated care, all receiving parenteral epinephrine. Patients with escalated care were more likely to be older, had previously required hospital admission for asthma and had severe respiratory distress at initial assessment.Of 1307 children with respiratory status data available, at arrival to hospital, the respiratory status of children had improved overall (normal/mild respiratory distress at initial assessment 847 (64.8%), normal/mild respiratory distress at hospital arrival 1142 (87.4%), p<0.0001).

CONCLUSIONS

Most children with acute exacerbations of asthma did not receive escalated therapy during their pre-hospital treatment from ambulance paramedics. Most patients were treated with inhaled bronchodilators only and clinically improved by the time they arrived in hospital.

Incidence of traumatic brain injuries in head-injured children with seizures

OBJECTIVE

Incidence and short-term outcomes of clinically important traumatic brain injury (ciTBI) in head-injured children presenting to ED with post-traumatic seizure (PTS) is not described in current literature.

METHODS

Planned secondary analysis of a prospective observational study undertaken in 10 Australasian Paediatric Research in Emergency Departments International Collaborative (PREDICT) network EDs between 2011 and 2014 of head-injured children <18 years with and without PTS. Clinical predictors and outcomes were analysed by attributable risk (AR), risk ratios (RR) and 95% confidence interval (CI), including the association with Glasgow Coma Scale (GCS) scores.

RESULTS

Of 20 137 head injuries, 336 (1.7%) had PTS with median age of 4.8 years. Initial GCS was 15 in 268/336 (79.8%, AR -16.1 [95% CI -20.4 to -11.8]), 14 in 24/336 (7.1%, AR 4.4 [95% CI 1.6-7.2]) and ≤13 in 44/336 (13.1%, AR 11.7 [95% CI 8.1-15.3]) in comparison with those without PTS, respectively. The ciTBI rate was 34 (10.1%) with PTS versus 219 (1.1%) without PTS (AR 9.0 [95% CI 5.8-12.2]) with 5/268 (1.9%), 6/24 (25.0%) and 23/44 (52.3%) with GCS 15, 14 and ≤13, respectively. In PTS, rates of admission ≥2 nights (34 [10.1%] AR 9.0 [95% CI 5.8-12.3]), intubation >24 h (9 [2.7%] AR 2.5 [95% CI 0.8-4.2]) and neurosurgery (8 [2.4%] AR 2.0 [95% CI 0.4-3.7]), were higher than those without PTS. Children with PTS and GCS 15 or 14 had no neurosurgery, intubations or death, with two deaths in children with PTS and GCS ≤13.

CONCLUSIONS

PTS was uncommon in head-injured children presenting to the ED but associated with an increased risk of ciTBI in those with reduced GCS on arrival.

Prevalence of high flow nasal cannula therapy use for management of infants with bronchiolitis in Australia and New Zealand

AIM

To determine the prevalence of high flow nasal cannula (HFNC) therapy in infants presenting to hospital in Australia and New Zealand with bronchiolitis over four bronchiolitis seasons. Secondary aims were to determine temporal trends in HFNC use, and associations between HFNC, hospital length of stay (LOS) and intensive care unit (ICU) admission.

METHODS

A planned sub-study of a multi-centre international cluster randomised controlled trial investigating knowledge translation strategies for a bi-national bronchiolitis guideline. Demographics, management and outcomes data were collected retrospectively for infants presenting with bronchiolitis to 26 hospitals between 1 May 2014 and 30 November 2017. Prevalence data are presented as absolute frequencies (95% confidence interval (CI)) with differences between groups for continuous and categorical variables analysed using linear and logistic regression, respectively.

RESULTS

11 715 infants were included with 3392 (29.0%, 95% CI (28.1-29.8%)) receiving oxygen therapy; of whom 1817 (53.6%, 95% CI (51.9-55.3%)) received HFNC. Use of oxygen therapy did not change over the four bronchiolitis seasons (P = 0.12), while the proportion receiving HFNC increased (2014, 336/2587 (43.2%); 2017, 609/3720 (57.8%); P ≤ 0.001). Infants who received HFNC therapy were not substantially different to infants who received oxygen therapy without HFNC. HFNC use was associated with increases in both hospital LOS (P < 0.001) and ICU admissions (P < 0.001).

CONCLUSION

Use of HFNC therapy for infants with bronchiolitis increased over 4 years. Of those who received oxygen therapy, the majority received HFNC therapy without improvement in hospital LOS or ICU admissions. Strategies to guide appropriate HFNC use in infants with bronchiolitis are required.

Modification of maternal late pregnancy sleep position: a survey evaluation of a New Zealand public health campaign

INTRODUCTION

A 'Sleep-On-Side When Baby's Inside' public health campaign was initiated in New Zealand in 2018. This was in response to evidence that maternal supine going-to-sleep position was an independent risk factor for stillbirth from 28 weeks' gestation. We evaluated the success of the campaign on awareness and modification of late pregnancy going-to-sleep position through nationwide surveys.

METHODS AND ANALYSIS

Two web-based cross-sectional surveys were conducted over 12 weeks in 2019-2020 in a sample of (1) pregnant women ≥28 weeks, primary outcome of going-to-sleep position; and (2) health professionals providing pregnancy care, primary outcome of knowledge of going-to-sleep position and late stillbirth risk. Univariable logistic regression was performed to identify factors associated with supine going-to-sleep position.

DISCUSSION

The survey of pregnant women comprised 1633 eligible participants. Going-to-sleep position last night was supine (30, 1.8%), non-supine (1597, 97.2%) and no recall (16, 1.0%). Supine position had decreased from 3.9% in our previous New Zealand-wide study (2012-2015). Most women (1412, 86.5%) had received sleep-on-side advice with no major resultant worry (1276, 90.4%). Two-thirds (918, 65.0%) had changed their going-to-sleep position based on advice, with most (611 of 918, 66.5%) reporting little difficulty. Supine position was associated with Māori (OR 5.05, 95% CI 2.10 to 12.1) and Asian-non-Indian (OR 4.20, 95% CI 1.27 to 13.90) ethnicity; single (OR 10.98, 95% CI 4.25 to 28.42) and cohabitating relationship status (OR 2.69, 95% CI 1.09 to 6.61); hospital-based maternity provider (OR 2.55, 95% CI 1.07 to 6.10); education overseas (OR 3.92, 95% CI 1.09 to 14.09) and primary-secondary level (OR 2.80, 95% CI 1.32 to 6.08); and not receiving sleep-on-side advice (OR 6.70, 95% CI 3.23 to 13.92). The majority of health professionals (709 eligible participants) reported awareness of supine going-to-sleep position and late stillbirth risk (543, 76.6%).

CONCLUSION

Most pregnant women had received and implemented sleep-on-side advice without major difficulty or concern. Some groups of women may need a tailored approach to acquisition of going-to-sleep position information.

Retinal microvasculature: population epidemiology and concordance in Australian children aged 11-12 years and their parents

OBJECTIVES

To describe distributions and concordance of retinal microvasculature measurements in a population-based sample of Australian parent-child dyads at child age 11-12 years.

DESIGN

Cross-sectional Child Health CheckPoint study, between waves 6 and 7 of the national population-based Longitudinal Study of Australian Children (LSAC).

SETTING

Assessment centres in seven Australian cities, February 2015-March 2016.

PARTICIPANTS

Of the 1874 participating families, 1288 children (51% girls) and 1264 parents (87% mothers, mean age 43.7) were analysed. Diabetic participants and non-biological pairs were excluded from concordance analyses.

OUTCOME MEASURES

Retinal photographs were taken by non-mydriatic fundus camera. Trained graders scored vascular calibre using semi-automated software, yielding estimates of central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) and arteriolar-venular ratio (AVR). Pearson's correlation coefficients and multivariable linear regression models assessed parent-child concordance. Survey weights and methods accounted for LSAC's complex sampling, stratification and clustering within postcodes.

RESULTS

Mean (SD) of CRAE and CRVE were larger in children (159.5 (11.8) and 231.1 (16.5) μm, respectively) than parents (151.5 (14.0) and 220.6 (19.0) μm), yielding similar AVR (children 0.69 (0.05), parents 0.69 (0.06)). Correlation coefficients for parent-child pairs were 0.22 (95% CI 0.16 to 0.27) for CRAE, 0.23 (95% CI 0.17 to 0.28) for CRVE and 0.18 (95% CI 0.13 to 0.24) for AVR. Mother-child and father-child values were similar (0.20 and 0.32 for CRAE, 0.22 and 0.29 for CRVE, respectively). Relationships attenuated slightly on adjustment for age, sex, blood pressure, diabetes and body mass index. Percentiles and concordance are presented for the whole sample and by sex.

CONCLUSIONS

Arteriolar and venular calibre were similar to previously documented measures in midlife adult and late childhood populations. Population parent-child concordance values align with moderate polygenic heritability reported in smaller studies.

Vascular function and stiffness: population epidemiology and concordance in Australian children aged 11-12 years and their parents

OBJECTIVES

To describe the epidemiology and parent-child concordance of vascular function in a population-based sample of Australian parent-child dyads at child age 11-12 years.

DESIGN

Cross-sectional study (Child Health CheckPoint), nested within a prospective cohort study, the Longitudinal Study of Australian Children (LSAC).

SETTING

Assessment centres in seven major Australian cities and eight regional towns or home visits, February 2015-March 2016.

PARTICIPANTS

Of all participating CheckPoint families (n=1874), 1840 children (49% girls) and 1802 parents (88% mothers) provided vascular function data. Survey weights and methods were applied to account for LSAC's complex sample design and clustering within postcodes and strata.

OUTCOME MEASURES

The SphygmoCor XCEL assessed vascular function, generating estimates of brachial and central systolic blood pressure and diastolic blood pressure, central pulse pressure, augmentation index and carotid-femoral pulse wave velocity. Pearson's correlation coefficients and multivariable linear regression models estimated parent-child concordance.

RESULTS

Hypertension was present in 3.9% of children and 9.0% of parents. Mean child and parent values for augmentation index were 4.5% (SD 11.6) and 21.3% (SD 12.3), respectively, and those for carotid-femoral pulse wave velocity were 4.48 m/s (SD 0.59) and 6.85 m/s (SD 1.14), respectively. Parent-child correlation for brachial systolic blood pressure was 0.20 (95% CI 0.15 to 0.24), brachial diastolic blood pressure 0.21 (95% CI 0.16 to 0.26), central systolic blood pressure 0.21 (95% CI 0.16 to 0.25), central diastolic blood pressure 0.21 (95% CI0.17 to 0.26), central pulse pressure 0.19 (95% CI 0.14 to 0.24), augmentation index 0.28 (95% CI 0.23 to 0.32) and pulse wave velocity 0.22 (95% CI 0.18 to 0.27).

CONCLUSIONS

We report Australian values for traditional and more novel vascular function markers, providing a reference for future population studies. Cross-generational concordance in multiple vascular function markers is already established by age 11-12 years, with mechanisms of heritability remaining to be explored.

Sleep: population epidemiology and concordance in Australian children aged 11-12 years and their parents

OBJECTIVES

To describe objectively measured sleep characteristics in children aged 11-12 years and in parents and to examine intergenerational concordance of sleep characteristics.

DESIGN

Population-based cross-sectional study (the Child Health CheckPoint), nested within the Longitudinal Study of Australian Children.

SETTING

Data were collected between February 2015 and March 2016 across assessment centres in Australian major cities and selected regional towns.

PARTICIPANTS

Of the participating CheckPoint families (n=1874), sleep data were available for 1261 children (mean age 12 years, 50% girls), 1358 parents (mean age 43.8 years; 88% mothers) and 1077 biological parent-child pairs. Survey weights were applied and statistical methods accounted for the complex sample design, stratification and clustering within postcodes.

OUTCOME MEASURES

Parents and children were asked to wear a GENEActive wrist-worn accelerometer for 8 days to collect objective sleep data. Primary outcomes were average sleep duration, onset, offset, day-to-day variability and efficiency. All sleep characteristics were weighted 5:2 to account for weekdays versus weekends. Biological parent-child concordance was quantified using Pearson's correlation coefficients in unadjusted models and regression coefficients in adjusted models.

RESULTS

The mean sleep duration of parents and children was 501 min (SD 56) and 565 min (SD 44), respectively; the mean sleep onset was 22:42 and 22:02, the mean sleep offset was 07:07 and 07:27, efficiency was 85.4% and 84.1%, and day-to-day variability was 9.9% and 7.4%, respectively. Parent-child correlation for sleep duration was 0.22 (95% CI 0.10 to 0.28), sleep onset was 0.42 (0.19 to 0.46), sleep offset was 0.58 (0.49 to 0.64), day-to-day variability was 0.25 (0.09 to 0.34) and sleep efficiency was 0.23 (0.10 to 0.27).

CONCLUSIONS

These normative values for objective sleep characteristics suggest that, while most parents and children show adequate sleep duration, poor-quality (low efficiency) sleep is common. Parent-child concordance was strongest for sleep onset/offset, most likely reflecting shared environments, and modest for duration, variability and efficiency.

Metabolomics: population epidemiology and concordance in Australian children aged 11-12 years and their parents

OBJECTIVES

Nuclear magnetic resonance (NMR) metabolomics is high throughput and cost-effective, with the potential to improve the understanding of disease and risk. We examine the circulating metabolic profile by quantitative NMR metabolomics of a sample of Australian 11-12 year olds children and their parents, describe differences by age and sex, and explore the correlation of metabolites in parent-child dyads.

DESIGN

The population-based cross-sectional Child Health CheckPoint study nested within the Longitudinal Study of Australian Children.

SETTING

Blood samples collected from CheckPoint participants at assessment centres in seven Australian cities and eight regional towns; February 2015-March 2016.

PARTICIPANTS

1180 children and 1325 parents provided a blood sample and had metabolomics data available. This included 1133 parent-child dyads (518 mother-daughter, 469 mother-son, 68 father-daughter and 78 father-son).

OUTCOME MEASURES

228 metabolic measures were obtained for each participant. We focused on 74 biomarkers including amino acid species, lipoprotein subclass measures, lipids, fatty acids, measures related to fatty acid saturation, and composite markers of inflammation and energy homeostasis.

RESULTS

We identified differences in the concentration of specific metabolites between childhood and adulthood and in metabolic profiles in children and adults by sex. In general, metabolite concentrations were higher in adults than children and sex differences were larger in adults than in children. Positive correlations were observed for the majority of metabolites including isoleucine (CC 0.33, 95% CI 0.27 to 0.38), total cholesterol (CC 0.30, 95% CI 0.24 to 0.35) and omega 6 fatty acids (CC 0.28, 95% CI 0.23 to 0.34) in parent-child comparisons.

CONCLUSIONS

We describe the serum metabolite profiles from mid-childhood and adulthood in a population-based sample, together with a parent-child concordance. Differences in profiles by age and sex were observed. These data will be informative for investigation of the childhood origins of adult non-communicable diseases and for comparative studies in other populations.

Body composition: population epidemiology and concordance in Australian children aged 11-12 years and their parents

OBJECTIVES

Overweight and obesity remain at historically high levels, cluster within families and are established risk factors for multiple diseases. We describe the epidemiology and cross-generational concordance of body composition among Australian children aged 11-12 years and their parents.

DESIGN

The population-based cross-sectional Child Health CheckPoint study, nested within the Longitudinal Study of Australian Children (LSAC).

SETTING

Assessment centres in seven major Australian cities and eight regional cities, or home visits; February 2015-March 2016.

PARTICIPANTS

Of all participating CheckPoint families (n=1874), body composition data were available for 1872 children (49% girls) and 1852 parents (mean age 43.7 years; 88% mothers), including 1830 biological parent-child pairs.

MEASURES

Height, weight, body mass index (BMI), waist circumference and waist-to-height ratio for all participants; body fat and fat-free mass by four-limb bioimpedence analysis (BIA) at assessment centres, or body fat percentage by two-limb BIA at home visits. Analysis: parent-child concordance was assessed using (i) Pearson's correlation coefficients, and (ii) partial correlation coefficients adjusted for age, sex and socioeconomic disadvantage. Survey weights and methods accounted for LSAC's complex sample design.

RESULTS

20.7% of children were overweight and 6.2% obese, as were 33.5% and 31.6% of parents. Boys and girls showed similar distributions for all body composition measures but, despite similar BMI and waist-to-height ratio, mothers had higher proportions of total and truncal fat than fathers. Parent-child partial correlations were greatest for height (0.37, 95% CI 0.33 to 0.42). Other anthropometric and fat/lean measures showed strikingly similar partial correlations, ranging from 0.25 (95% CI 0.20 to 0.29) for waist circumference to 0.30 (95% CI 0.25 to 0.34) for fat-free percentage. Whole-sample and sex-specific percentile values are provided for all measures.

CONCLUSIONS

Excess adiposity remains prevalent in Australian children and parents. Moderate cross-generational concordance across all measures of leanness and adiposity is already evident by late childhood.

Hearing, speech reception, vocabulary and language: population epidemiology and concordance in Australian children aged 11 to 12 years and their parents

OBJECTIVES

To describe the epidemiology and parent-child concordance of hearing, speech reception, vocabulary and language in Australian parent-child dyads at child age 11 to 12 years.

DESIGN

Population-based cross-sectional study (Child Health CheckPoint) nested within the Longitudinal Study of Australian Children.

SETTING

Assessment centres in seven Australian cities and eight regional towns or home visits around Australia, February 2015 to March 2016.

PARTICIPANTS

Of all participating CheckPoint families (n=1874), 1516 children (50% female) and 1520 parents (87% mothers, mean age 43.8 years) undertook at least one of four measurements of hearing and language.

OUTCOME MEASURES

Hearing threshold (better ear mean of 1, 2 and 4 kHz) from pure-tone audiometry, speech reception threshold, receptive vocabulary, expressive and receptive languages using a sentence repetition task. Parent-child concordance was examined using Pearson's correlation coefficients and adjusted linear regression models. Survey weights and methods accounted for Longitudinal Study of Australian Children's complex sampling and stratification.

RESULTS

Children had a similar speech reception threshold to parents (children mean -14.3, SD 2.4; parents -14.9, SD 3.2 dB) but better hearing acuity (children 8.3, SD 6.3; parents 13.4, SD 7.0 decibels hearing level). Standardised sentence repetition scores were similar (children 9.8, SD 2.9; parents 9.1, SD 3.3) but, as expected, parents had superior receptive vocabularies. Parent-child correlations were higher for the cognitively-based language measures (vocabulary 0.31, 95% CI 0.26 to 0.36; sentence repetition 0.29, 95% CI 0.24 to 0.34) than the auditory measures (hearing 0.18, 95% CI 0.13 to 0.23; speech reception threshold 0.18, 95% CI 0.13 to 0.22). Mother-child and father-child concordances were similar for all measures.

CONCLUSIONS

We provide population reference values for multiple measures spanning auditory and verbal communication systems in children and mid-life adults. Concordance values aligned with previous twin studies and offspring studies in adults, in keeping with polygenic heritability that is modest for audition but around 60% for language by late childhood.

Population health bio-phenotypes in 11-12 year old children and their midlife parents: Growing Up in Australia's Child Health CheckPoint

In an ambitious undertaking, Growing Up in Australia's Child Health CheckPoint streamlined and implemented wide-ranging population phenotypes and biosamples relevant to non-communicable diseases in nearly 1900 parent-child dyads throughout Australia at child aged 11-12 years. This BMJ Open Special Issue describes the methodology, epidemiology and parent-child concordance of 14 of these phenotypes, spanning cardiovascular, respiratory, bone, kidney, hearing and language, body composition, metabolic profiles, telomere length, sleep, physical activity, snack choice and health-related quality of life. The Special Issue also includes a cohort summary and study methodology paper.

Carotid artery intima-media thickness, distensibility and elasticity: population epidemiology and concordance in Australian children aged 11-12 years old and their parents

OBJECTIVES

To describe a well-established marker of cardiovascular risk, carotid intima-media thickness (IMT) and related measures (artery distensibility and elasticity) in children aged 11-12 years old and mid-life adults, and examine associations within parent-child dyads.

DESIGN

Cross-sectional study (Child Health CheckPoint), nested within a prospective cohort study, the Longitudinal Study of Australian Children (LSAC).

SETTING

Assessment centres in seven Australian major cities and eight selected regional towns, February 2015 to March 2016.

PARTICIPANTS

Of all participating CheckPoint families (n=1874), 1489 children (50.0% girls) and 1476 parents (86.8% mothers) with carotid IMT data were included. Survey weights and methods were applied to account for LSAC's complex sample design and clustering within postcodes and strata.

OUTCOME MEASURES

Ultrasound of the right carotid artery was performed using standardised protocols. Primary outcomes were mean and maximum far-wall carotid IMT, quantified using semiautomated edge detection software. Secondary outcomes were carotid artery distensibility and elasticity. Pearson's correlation coefficients and multivariable linear regression models were used to assess parent-child concordance. Random effects modelling on a subset of ultrasounds (with repeated measurements) was used to assess reliability of the child carotid IMT measure.

RESULTS

The average mean and maximum child carotid IMT were 0.50 mm (SD 0.06) and 0.58 mm (SD 0.05), respectively. In adults, average mean and maximum carotid IMT were 0.57 mm (SD 0.07) and 0.66 mm (SD 0.10), respectively. Mother-child correlations for mean and maximum carotid IMT were 0.12 (95% CI 0.05 to 0.23) and 0.10 (95% CI 0.03 to 0.21), respectively. For carotid artery distensibility and elasticity, mother-child correlations were 0.19 (95% CI 0.10 to 0.25) and 0.11 (95% CI 0.02 to 0.18), respectively. There was no strong evidence of father-child correlation in any measure.

CONCLUSIONS

We provide Australian values for carotid vascular measures and report a modest mother-child concordance. Both genetic and environmental exposures are likely to contribute to carotid IMT.

Physical activity and sedentary activity: population epidemiology and concordance in Australian children aged 11-12 years and their parents

OBJECTIVES

To describe the epidemiology and parent-child concordance of objectively measured physical activity in a population-based sample of Australian parent-child dyads.

DESIGN

Cross-sectional study (Child Health CheckPoint) nested within the Longitudinal Study of Australian Children.

SETTING

Assessment centres in seven Australian cities and eight regional towns or home visits; February 2015-March 2016.

PARTICIPANTS

Of all CheckPoint families (n=1874), 1261 children (50% girls) and 1358 parent (88% mothers) provided objectively measured activity data, comprising 1077 parent-child dyads.

OUTCOME MEASURES

Activity behaviour was assessed by GENEActiv accelerometer. Duration of moderate-to-vigorous physical activity (MVPA) and vigorous physical activity and sedentary behaviour (SB) were derived using Cobra custom software, along with MVPA/SB fragmentation and mean daily activity. Pearson's correlation coefficients and linear regression estimated parent-child concordance. Survey weights and methods accounted for the complex sample design and clustering.

RESULTS

Although parents had average lower accelerometry counts than children (mean [SD] 209 [46] vs 284 [71] g.min), 93% of parents met MVPA daily duration guidelines on published cutpoints (mean [SD] 125 [63] min/day MVPA), compared with only 15% of children (mean 32 [27] min). Parents showed less daily SB duration (parents: 540 [101], children: 681 [69] minutes) and less fragmented accumulation of MVPA (parents: α=1.85, children: α=2.00). Parent-child correlation coefficients were 0.16 (95% CI 0.11 to 0.22) for MVPA duration, 0.10 (95% CI 0.04 to 0.16) for MVPA fragmentation, 0.16 (95% CI 0.11 to 0.22) for SB duration and 0.18 (95% CI 0.12 to 0.23) for SB fragmentation.

CONCLUSIONS

Standardised cutpoints are needed for objective activity measures to inform activity guidelines across the lifecourse. This may reflect large amounts of time in non-shared environments (school and work).

Child Health CheckPoint: cohort summary and methodology of a physical health and biospecimen module for the Longitudinal Study of Australian Children

OBJECTIVES

'Growing Up in Australia: The Longitudinal Study of Australian Children' (LSAC) is Australia's only nationally representative children's longitudinal study, focusing on social, economic, physical and cultural impacts on health, learning, social and cognitive development. LSAC's first decade collected wide-ranging repeated psychosocial and administrative data; here, we describe the Child Health CheckPoint, LSAC's dedicated biophysical module.

DESIGN, SETTING AND PARTICIPANTS

LSAC recruited a cross-sequential sample of 5107 infants aged 0-1 year and a sample of 4983 children aged 4-5 years in 2004, since completing seven biennial visits. CheckPoint was a cross-sectional wave that travelled Australia in 2015-2016 to reach LSAC's younger cohort at ages 11-12 years between LSAC waves 6 and 7. Parent-child pairs participated in comprehensive assessments at 15 Assessment Centres nationwide or, if unable to attend, a shorter home visit.

MEASURES

CheckPoint's intergenerational, multidimensional measures were prioritised to show meaningful variation within normal ranges and capture non-communicable disease (NCD) phenotype precursors. These included anthropometry, physical activity, fitness, time use, vision, hearing, and cardiovascular, respiratory and bone health. Biospecimens included blood, saliva, buccal swabs (also from second parent), urine, hair and toenails. The epidemiology and parent-child concordance of many measures are described in separate papers.

RESULTS

1874 (54% of eligible) parent-child pairs and 1051 second parents participated. Participants' geographical distribution mirrored the broader Australian population; however, mean socioeconomic position and parental education were higher and fewer reported non-English-speaking or Indigenous backgrounds. Application of survey weights partially mitigates that the achieved sample is less population representative than previous waves of LSAC due to non-random attrition. Completeness was uniformly high for phenotypic data (>92% of eligible), biospecimens (74%-97%) and consent (genetic analyses 98%, accessing neonatal blood spots 97%, sharing 96%).

CONCLUSIONS

CheckPoint enriches LSAC to study how NCDs develop at the molecular and phenotypic levels before overt disease emerges, and clarify the underlying dimensionality of health in childhood and mid-adulthood.

Food choices: concordance in Australian children aged 11-12 years and their parents

OBJECTIVES

Snack foods-typically high in salt, sugar, fat and/or energy-are likely important to the obesity epidemic. In the context of a population-based health assessment involving parent-child dyads at child age 11-12 years, we report cross-generational concordance in intake at a controlled snack food observation.

DESIGN

Cross-sectional study (Child Health CheckPoint), nested within the Longitudinal Study of Australian Children.

SETTING

Assessment centres in seven Australian cities, February 2015-March 2016.

PARTICIPANTS

Of all participating CheckPoint families (n=1874), 1299 children (50.3% girls) and 1274 parents (85.9% mothers) with snack data were included. Survey weights and methods were applied to account for the clustered multistage sample design.

OUTCOME MEASURES

Partway through the 3.5-hour assessment, parents and children attended Food Stop separately for a timed 15 min 'snack break'. One of four standardised box size/content combinations was randomly provided to all participants on any given day. Total food mass, energy, nutrients and sodium consumed was measured to the nearest 1 g. Pearson's correlation coefficients and adjusted multivariable linear regression models assessed parent-child concordance in each variable.

RESULTS

Children consumed less grams (151 g [SD 80] vs 165 g [SD 79]) but more energy (1393 kJ [SD 537] vs 1290 kJ [SD 658]) than parents. Parent-child concordance coefficients were small, ranging from 0.07 for sodium intake to 0.17 for carbohydrate intake. Compared with children with parents' energy intake on the 10th centile, children whose parents were on the 90th centile ate on average 227 kJ more. If extrapolated to one similar unsupervised snack on a daily basis, this equates to an additional 83 050 kJ per year, which could have a cumulative impact on additional body fat.

CONCLUSIONS

Although modest at an individual level, this measured parent-child concordance in unsupervised daily snack situations could account for substantial annual population differences in energy, fat and sodium intake for children aged 11-12 years.

TRIAL REGISTRATION NUMBER

ISRCTN12538380.

Telomere length: population epidemiology and concordance in Australian children aged 11-12 years and their parents

OBJECTIVES

To (1) describe the epidemiology of child and adult telomere length, and (2) investigate parent-child telomere length concordance.

DESIGN

Population-based cross-sectional study within the Longitudinal Study of Australian Children.

SETTING

Assessment centres in seven major Australian cities and eight selected regional towns; February 2015 to March 2016.

PARTICIPANTS

Of 1874 participating families, telomere data were available for analysis for 1206 children and 1343 parents, of whom 1143 were parent-child pairs. There were 589 boys and 617 girls; 175 fathers and 1168 mothers.

OUTCOME MEASURES

Relative telomere length (T/S ratio), calculated by comparing telomeric DNA (T) level with the single copy (S) beta-globin gene in venous blood-derived genomic DNA by quantitative real-time PCR.

RESULTS

Mean T/S ratio for all children, boys and girls was 1.09 (SD 0.56), 1.05 (SD 0.53) and 1.13 (SD 0.59), respectively. Mean T/S ratio for all parents, fathers and mothers was 0.81 (SD 0.37), 0.82 (SD 0.36) and 0.81 (SD 0.38), respectively. Parent-child T/S ratio concordance was moderate (correlation 0.24). In adjusted regression models, one unit higher parent T/S ratio was associated with 0.36 (estimated linear regression coefficient (β); 95% CI 0.28 to 0.45) higher child T/S ratio. Concordance was higher in the youngest parent-age tertile (β 0.49; 95% CI 0.34 to 0.64) compared with the middle (β 0.35; 95% CI 0.21 to 0.48) and oldest tertile (β 0.26; 95% CI 0.11 to 0.41; p-trend 0.04). Father-child concordance was 0.34 (95% CI 0.18 to 0.48), while mother-child was 0.22 (95% CI 0.17 to 0.28).

CONCLUSIONS

We provide telomere length population values for children aged 11-12 years and their mid-life parents. Relative telomere length was shorter in adults than children, as expected. There was modest evidence of parent-child concordance, which diminished with increasing parent age.