Importance:Systemic postnatal corticosteroids have been shown to reduce rates of bronchopulmonary dysplasia (BPD) in infants born preterm, but both corticosteroids and BPD are associated with cerebral palsy. Objective:To describe how the association between systemic postnatal corticosteroids and survival free of cerebral palsy varies with the risk of BPD in infants born preterm, and if the association differs between dexamethasone and hydrocortisone, or with age at starting treatment. Design, Setting, and Participants:This comparative effectiveness research used weighted meta-regression analysis of eligible randomized clinical trials (RCTs) of systemic postnatal corticosteroids reported from June 1989 through March 2022 that included rates of all of BPD, mortality, and cerebral palsy in neonatal intensive care units in 10 countries. Infants born preterm at risk of BPD were included. Data were analyzed from April and July 2024. Interventions:Systemic dexamethasone or hydrocortisone. Main Outcomes and Measures:Type and timing of corticosteroid, control group rate of BPD, and risk difference in survival free of cerebral palsy between corticosteroid and control arms. Results:Twenty-six RCTs with data on 3700 randomized infants were eligible; 18 (69%) investigated dexamethasone and 8 (31%) hydrocortisone; 12 (46%) started treatment in the first week after birth. There was evidence for a differential association of the type of corticosteroid with the effect of systemic dexamethasone on survival free of cerebral palsy and the risk of BPD in control groups (interaction coefficient, 0.54; 95% CI, 0.25-0.82; P = .001). For dexamethasone, for every 10-percentage point increase in the risk of BPD, the risk difference for survival free of cerebral palsy increased by 3.74% (95% CI, 1.54 to 5.93; P = .002). Dexamethasone was associated with improved survival free of cerebral palsy at a risk of BPD greater than 70%. Conversely, dexamethasone was associated with harm at a risk of BPD less than 30%. There was some evidence for a negative association with hydrocortisone, with possible benefit with risk of BPD less than 30%. There was no strong evidence for a differential effect of timing among those treated with dexamethasone (interaction coefficient, 0.13; 95% CI, -0.04 to 0.30; P = .14). Conclusions and Relevance:The findings suggest that dexamethasone (compared with control) was associated with improved rates of survival free of cerebral palsy in infants at high risk of BPD but should be avoided in those at low risk. A role for hydrocortisone is uncertain.

Rationale: The effect of moderate to late preterm (MLP) birth (32-36 completed weeks' gestation) on childhood respiratory health is unclear. Objectives: To assess the effect of being born MLP, compared with being born at term (≥37 completed weeks' gestation), on lung function and respiratory morbidity at 9-10 years of age. Methods: A prospective cohort study was conducted among children born MLP or at term at the Royal Women's Hospital (Victoria, Australia). Participants completed pre and postbronchodilator spirometry, measurement of diffusing capacity of the lung for carbon monoxide, plethysmography, and multiple-breath washout at 9-10 years of age. Parents completed the ISAAC (International Study of Asthma and Allergies in Childhood) questionnaire. Mean differences in z-scores of lung function outcomes and risk ratio for ISAAC outcomes between those born MLP and those born at term were estimated using regression models with adjustment for potential confounding. Multiple imputation was used to handle missing data. Results: A total of 148 of 201 children born MLP and 120 of 201 term-born control subjects were assessed at 9-10 years. Compared with control subjects, children born MLP had lower mean z-scores for forced expiratory volume in 1 second (mean difference, -0.35 [95% confidence interval (CI), -0.61 to -0.08]), ratio of forced expiratory volume in 1 second to forced vital capacity (mean difference, -0.29 [95% CI, -0.58 to -0.01]), forced expiratory flow at 25-75% of forced vital capacity (-0.33 [95% CI, -0.62 to -0.04]), and diffusing capacity of the lung for carbon monoxide (-0.24 [95% CI, -0.45 to -0.03]). Participants born MLP had higher risk of experiencing asthma symptoms (risk ratio, 1.52 [95% CI, 1.08-2.14]). Conclusions: Children born MLP have lower lung function and increased risk of exhibiting asthma symptoms compared with term-born peers at 9-10 years. Such findings at the end of the first decade of life may portend adverse consequences for respiratory health in adulthood.

Despite providing intensive care to more infants born <24 weeks’ gestation, data on school-age outcomes, critical for counselling and decision-making, are sparse. Objective To compare major neurosensory, cognitive and academic impairment among school-aged children born extremely preterm at 22–23 weeks’ gestation (EP22–23) with those born 24–25 weeks (EP24–25), 26–27 weeks (EP26–27) and term (≥37 weeks). Design Three prospective longitudinal cohorts. Setting Victoria, Australia. Participants All EP live births (22–27 weeks) and term-born controls born in 1991–1992, 1997 and 2005. Main outcome measures At 8 years, major neurosensory disability (any of moderate/severe cerebral palsy, IQ <−2 SD relative to controls, blindness or deafness), motor, cognitive and academic impairment, executive dysfunction and poor health utility. Risk ratios (RRs) and risk differences between EP22–23 (reference) and other gestational age groups were estimated using generalised linear models, adjusted for era of birth, social risk and multiple birth. Results The risk of major neurosensory disability was higher for EP22–23 (n=21) than more mature groups (168 EP24–25; 312 EP26–27; 576 term), with increasing magnitude of difference as the gestation increased (adjusted RR (95% CI) compared with EP24–25: 1.39 (0.70 to 2.76), p=0.35; EP26–27: 1.85 (0.95 to 3.61), p=0.07; term: 13.9 (5.75 to 33.7), p<0.001). Similar trends were seen with other outcomes. Two-thirds of EP22–23 survivors were free of major neurosensory disability. Conclusions Although children born EP22–23 experienced higher rates of disability and impairment at 8 years than children born more maturely, many were free of major neurosensory disability. These data support providing active care to infants born EP22–23.

Importance Although children born moderate to late preterm (MLP; 32-36 weeks' gestation) have more neurodevelopmental problems compared with children born early term or later (>= 37 weeks' gestation), detailed understanding of affected domains at school age is lacking. Little is known of risk factors for poorer development. Objective To examine whether being born MLP compared with being born early term or later is associated with neurodevelopmental outcomes at age 9 years and to describe factors associated with poorer neurodevelopment in children born MLP. Design, Setting, and Participants This prospective, longitudinal cohort study recruited children born MLP and children born early term or later with healthy birth weight (>= 2500 g) at a single tertiary hospital in Melbourne, Victoria, Australia, between December 7, 2009, and March 26, 2014. Nine-year follow-up occurred between June 20, 2019, and February 27, 2024. Exposure Moderate to late preterm birth. Main Outcomes and Measures Cognitive ability, academic performance, motor function, behavior, and social communication skills, assessed at 9-year follow-up. Group differences were estimated using linear, logistic, or quantile regression adjusted for multiple birth and socioeconomic risk. Multiple imputation was used to account for missing data. Associations of antenatal and neonatal factors and developmental delay at 2 years with poorer 9-year neurodevelopment were explored using univariable regression. Results Of 201 recruited children born MLP and 201 born early term or later, 159 born MLP (79.1%; 72 [45.3%] male) and 137 born early term or later (68.2%; 75 [54.7%] male) were assessed. Compared with children born early term or later, children born MLP had lower mean (SD) full-scale IQ scores (105.2 [13.6] vs 110.1 [13.0]; adjusted mean difference, -4.4 [95% CI, -7.7 to -1.0]) and poorer performance for cognitive domains, including verbal comprehension, visuospatial, and working memory. They also had poorer academic performance: pseudoword decoding (mean [SD] score, 103.0 [11.3] vs 107.3 [10.5]; adjusted mean difference, -4.0 [95% CI, -7.0 to -1.1]) and mathematics (mean [SD] score, 96.6 [14.7] vs 101.5 [14.5]; adjusted mean difference, -5.0 [95% CI, -8.8 to -1.2]). Children born MLP had similar manual dexterity to those born early term or later (mean [SD] score, 8.4 [3.5] vs 9.1 [3.4]; adjusted mean difference, -0.9 [95% CI, -1.8 to 0.04]) but more behavioral difficulties (50 of 158 [31.7%] vs 29 of 135 [21.5%]; adjusted risk ratio, 1.57 [95% CI, 1.06-2.33]). Developmental delay at 2 years was associated with poorer 9-year neurodevelopment across multiple domains. Conclusions and Relevance In this longitudinal cohort study of children born MLP, neurodevelopmental challenges persisted into school age. An assessment at age 2 years may assist in identifying children born MLP who are at risk of school-age impairments.

Multiple imputation (MI) is a popular method for handling missing data. Auxiliary variables can be added to the imputation model(s) to improve MI estimates. However, the choice of which auxiliary variables to include in the imputation model is not always straightforward. Including too few may lead to important information being discarded, but including too many can cause problems with convergence of the estimation procedures for imputation models. Several data-driven auxiliary variable selection strategies have been proposed. This paper uses a simulation study and a case study to provide a comprehensive comparison of the performance of eight auxiliary variable selection strategies, with the aim of providing practical advice to users of MI. A complete case analysis and an MI analysis with all auxiliary variables included in the imputation model (the full model) were also performed for comparison. Our simulation study results suggest that the full model outperforms all auxiliary variable selection strategies, providing further support for adopting an inclusive auxiliary variable strategy where possible. Auxiliary variable selection using the Least Absolute Selection and Shrinkage Operator (LASSO) was the best performing auxiliary variable selection strategy overall and is a promising alternative when the full model fails. All MI analysis strategies that we were able to apply to the case study led to similar estimates.

BACKGROUND:Associations of neonatal infection with brain growth and later neurodevelopmental outcomes in very preterm (VP) infants are unclear. This study aimed to assess associations of neonatal sepsis in VP infants with (1) brain growth from term-equivalent age to 13 years; and (2) 13-year brain volume and neurodevelopmental outcomes. METHODS:224 infants born VP ( < 30 weeks' gestation/<1250 g birthweight) were recruited. Longitudinal brain volumes for 68 cortical and 14 subcortical regions were derived from MRI at term-equivalent, 7 and/or 13 years of age for 216 children (79 with neonatal sepsis and 137 without). 177 children (79%) had neurodevelopmental assessments at age 13. Of these, 63 with neonatal sepsis were compared with 114 without. Brain volumetric growth trajectories across time points were compared between sepsis and no-sepsis groups using mixed effects models. Linear regressions compared brain volume and neurodevelopmental outcome measures at 13 years between sepsis and no sepsis groups. RESULTS:Growth trajectories were similar and there was little evidence for differences in brain volumes or neurodevelopmental domains at age 13 years between those with or without sepsis. CONCLUSIONS:Neonatal sepsis in children born VP does not appear to disrupt subsequent brain development, or to have functional consequences in early adolescence. IMPACT STATEMENT:Neonatal sepsis has been associated with poorer short-term neurodevelopmental outcomes and reduced brain volumes in very preterm infants. This manuscript provides new insights into the long-term brain development and neurodevelopmental outcomes of very preterm-born children who did or did not have neonatal sepsis. We found that regional brain volumes up to 13 years, and neurodevelopmental outcomes at age 13, were similar between those with and without neonatal sepsis. The links between neonatal sepsis and long-term neurodevelopment remain unclear.

AIM:To explore the impact of blood pressure on cognitive outcomes at 18 years of age in individuals born extremely preterm (<28 weeks' gestation) and at term (≥37 weeks' gestation). METHODS:Prospective longitudinal cohort comprising 136 young adults born extremely preterm and 120 matched term controls born in Victoria, Australia in 1991 and 1992. Using linear regression, we analysed the relationships between 24-h mean ambulatory blood pressure, systolic and diastolic hypertension with cognitive outcomes. RESULTS:For both birth groups combined, higher 24-h mean ambulatory blood pressure and systolic hypertension were associated with similar or worse cognitive outcomes. The strongest relationships were between higher 24-h mean ambulatory blood pressure and systolic hypertension with poorer general intellect, visual learning and visual memory. We found little evidence that relationships between ambulatory blood pressure and cognitive outcomes differed by birth group. CONCLUSION:Higher 24-h mean ambulatory blood pressure and systolic hypertension were associated with poorer cognitive outcomes in individuals born extremely preterm and at term, particularly in general intelligence and visual memory.

Introduction: Cystic fibrosis transmembrane conductance regulator (CFTR) modulator elexacaftor/tezacaftor/ivacaftor (ETI) significantly improves lung function but its effect on mental health and sleep remains poorly understood. We report on mental health, sleep, and respiratory health outcomes of adolescents with CF commenced on ETI therapy, and monitored the prevalence of neuropsychiatric issues through the coronavirus disease 2019 pandemic. Methods: We conducted a prospective longitudinal study of 31 adolescents (aged 10-18 years) from July 2021 to October 2022. Data collected include demographics, Patient Health Questionnaire-9 (PHQ-9), General Anxiety Disorder-7 (GAD-7), Pediatric Daytime Sleepiness Scale (PDSS), Sleep Disturbance Scale for Children (SDSC) scores, and FEV1 percent predicted. Twenty of 31 adolescents had data before and after ETI initiation. Mean differences (MD) in mental health, sleep, and respiratory health pre- and post-ETI therapy commencement were estimated using paired t-tests. The prevalence and trajectories of anxiety, depression, and sleep disturbance were described between the ETI epochs, and over the pandemic period. Results: FEV1 improved following ETI therapy commencement (MD, 95% confidence interval [CI]: 7.1% (4.7%-9.6%) whereas PHQ-9, GAD-7, PDSS, and SDSC scores did not change significantly. Ten percent of participants developed new-onset anxiety/depression concerns and 10% developed new sleep concerns following ETI initiation. Conclusion: This is the first prospective longitudinal study of mental health and sleep changes after ETI commencement in adolescents with CF. Although respiratory outcomes improved, ETI did not improve anxiety, depression or sleep.

Australian Governments are increasingly understanding the impacts of early adversity, evidenced by ongoing policy and investment in two of the most widely implemented early interventions: nurse home visiting (NHV) and early childhood education and care (ECEC). Neither intervention fully redresses the developmental inequities engendered by early adversity, yet their synergistic impacts ("dynamic complementarity") are unknown. In this research, we aimed to (1) inform evaluation of policy implementation by (2) experimentally testing the dynamic complementarity of NHV and ECEC. We capitalised on an opportunity afforded by the Australian "right@home" randomised trial, which involved 722 pregnant women experiencing adversity, randomised to receive NHV or usual care to child age 2 years. Detailed data describing family-accessed ECEC were collected from parents at 3-4 years, and "quality ECEC" was categorised according to meeting quality recommendations defined by Australian policy and provision. Children's developmental outcomes (language, executive functioning, behaviour and well-being) were parent-reported or assessed directly at 4 years. At 4 years, 33 per cent of families had received neither intervention; 40 per cent NHV only; 14 per cent quality ECEC only; and 13 per cent had received both. We used linear regression to estimate differences in mean outcomes between exposure groups, including interaction between NHV and ECEC. Unadjusted analyses indicated modest effects of the combination of NHV and ECEC, which attenuated after adjustment for socioeconomic confounders. We present the design and preliminary findings as an approach that could be used to evaluate equitable implementation at scale and enable policymakers to determine the most effective evidence-based policy.

Background Missing data are common in observational studies and often occur in several of the variables required when estimating a causal effect, i.e. the exposure, outcome and/or variables used to control for confounding. Analyses involving multiple incomplete variables are not as straightforward as analyses with a single incomplete variable. For example, in the context of multivariable missingness, the standard missing data assumptions (“missing completely at random”, “missing at random” [MAR], “missing not at random”) are difficult to interpret and assess. It is not clear how the complexities that arise due to multivariable missingness are being addressed in practice. The aim of this study was to review how missing data are managed and reported in observational studies that use multiple imputation (MI) for causal effect estimation, with a particular focus on missing data summaries, missing data assumptions, primary and sensitivity analyses, and MI implementation. Methods We searched five top general epidemiology journals for observational studies that aimed to answer a causal research question and used MI, published between January 2019 and December 2021. Article screening and data extraction were performed systematically. Results Of the 130 studies included in this review, 108 (83%) derived an analysis sample by excluding individuals with missing data in specific variables (e.g., outcome) and 114 (88%) had multivariable missingness within the analysis sample. Forty-four (34%) studies provided a statement about missing data assumptions, 35 of which stated the MAR assumption, but only 11/44 (25%) studies provided a justification for these assumptions. The number of imputations, MI method and MI software were generally well-reported (71%, 75% and 88% of studies, respectively), while aspects of the imputation model specification were not clear for more than half of the studies. A secondary analysis that used a different approach to handle the missing data was conducted in 69/130 (53%) studies. Of these 69 studies, 68 (99%) lacked a clear justification for the secondary analysis. Conclusion Effort is needed to clarify the rationale for and improve the reporting of MI for estimation of causal effects from observational data. We encourage greater transparency in making and reporting analytical decisions related to missing data.

Objective: To describe associations between executive function (EF) domains (attentional control, information processing, cognitive flexibility, and goal setting) and concurrent math computation performance at age 7 and 13 years in children born <30 weeks' gestation or weighing <1,250 g, and second, to examine the impact of 7-year EF on math performance at 13 years. Method: In a prospective, longitudinal cohort of children born <30 weeks' gestation or with a birthweight <1,250 g, assessment of EF and math performance was undertaken at 7 (n = 187) and 13 years (n = 174). Linear regression models were used to describe associations between EF domains with math performance at both time points, as well as to examine the impact of EF at 7 years on math performance at 13 years. Results: At 7 and 13 years, all EF domains were positively and strongly associated with concurrent math performance (beta = 11.35, 95% CI [9.28, 13.41] to beta = 13.79, 95% CI [11.59, 15.98]). All EF domains at age 7 years were positively associated with math performance at 13 years, with the strongest associations observed for cognitive flexibility (beta = 10.79 [8.64, 12.94]) and goal setting (beta = 10.37 [8.08, 12.67]). Conclusions: This study provides evidence that EF is strongly associated with math performance in children born <30 weeks' gestation or with a birthweight <1,250 g and highlights the importance of early cognitive flexibility and goal setting performance for future math performance.

AIM:To compare trajectories of social functioning in peer problems and prosocial behavior from 5 to 13 years between individuals born very preterm (VPT) and full-term (FT). METHODS:Participants were from the Victorian Infant Brain Study (VIBeS) longitudinal cohort, consisting of 224 individuals born VPT and 77 born FT recruited at birth. Social functioning was measured using the parent-rated Strengths and Difficulties Questionnaire (SDQ) peer problems and prosocial behavior subscales at 5, 7, and 13 years' corrected age. Multilevel mixed effects models were fitted. RESULTS:Peer problems increased with age (adjusted mean difference per year = 0.04, 95% confidence interval [CI] = 0.01, 0.07, p = 0.02), with higher peer problems in the VPT compared with the FT group (adjusted mean difference between groups = 0.46, 95% CI = 0.06, 0.86, p = 0.02). Prosocial behavior increased from early to middle childhood and decreased approaching adolescence, but was similar between VPT and FT groups (adjusted mean difference between groups = -0.05, 95% CI = -0.50, 0.40, p = 0.82). CONCLUSION:Children born VPT are at greater risk for peer problems than FT peers and may benefit from receiving greater early social support.

ObjectiveTo clarify the relationships of three definitions of severity of bronchopulmonary dysplasia (BPD) with adverse neurodevelopmental and respiratory outcomes at early school-age.Study designParticipants comprised 218 consecutive survivors to 7-8 years of age born either <28 weeks’ gestation or weighing <1000 g in Victoria, Australia, in 2005. BPD was classified as none, Grade 1 (mild), Grade 2 (moderate), or Grade 3 (severe), using two commonly accepted definitions: 1) Jobe2001, and 2) Higgins2018, and our own 3) VICS2005, adapted from Jensen2019. Outcomes included major neurodevelopmental disability, low intelligence quotient and academic achievement, poor motor function, and poor respiratory function as assessed by spirometry. Outcomes for children with each grade of BPD were compared with children with no BPD.ResultsOf the 218 survivors, 132 (61%) had BPD on Jobe2001 criteria, and 113 (52%) had BPD on both Higgins2018 and VICS2005 criteria. Grade 1 on any criteria was not associated with any adverse neurodevelopmental outcomes. Grade 1 on both Higgins2018 and VICS2005 was associated with reduced spirometry. Grade 2 on both Higgins2018 and VICS2005, and Grade 3 on all criteria were associated with increased risk for both adverse neurodevelopmental and respiratory outcomes.ConclusionsCompared with no BPD, receiving additional oxygen up to 29% but no positive pressure support at 36 weeks’ postmenstrual age increased the risk of abnormal respiratory function but not adverse neurodevelopment. Receiving ≥30% oxygen or any positive pressure support at 36 weeks increased the risk of both adverse outcomes.

Objective To investigate the effect of physical activity (PA) on development (motor, cognitive, social-emotional) in children 4–5 years old born <30 weeks’ gestation, and to describe subgroups of children at risk of low PA in this cohort. Design Longitudinal cohort study. Patients 123 children born <30 weeks were recruited at birth and assessed between 4 and 5 years’ corrected age. Main outcome measures Development was assessed using the Movement Assessment Battery for Children, Second Edition (MABC-2), Little Developmental Coordination Disorder Questionnaire (L-DCDQ), Wechsler Preschool and Primary Scale of Intelligence (Fourth Edition; WPPSI-IV), and Strengths and Difficulties Questionnaire (SDQ). To measure PA, children wore an accelerometer and parents completed a diary for 7 days. Effects of PA on developmental outcomes, and associations between perinatal risk factors and PA, were estimated using linear regression. Results More accelerometer-measured PA was associated with better MABC-2 aiming and catching scores (average standard score increase per hour increase in PA: 0.54, 95% CI 0.11, 0.96; p=0.013), and lower WPPSI-IV processing speed index scores (average composite score decrease per hour increase in PA: −2.36, 95% CI −4.19 to –0.53; p=0.012). Higher accelerometer-measured PA was associated with better SDQ prosocial scores. Major brain injury in the neonatal period was associated with less moderate-vigorous and less unstructured PA at 4–5 years. Conclusions Higher levels of PA are associated with aspects of motor, cognitive and social-emotional skill development in children 4–5 years old born <30 weeks. Those with major brain injury in the neonatal period may be more vulnerable to low PA at preschool age.

Objective To determine the accuracy of two developmental screening questionnaires to detect cognitive or language delay, defined using the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III), in children born extremely preterm (EP: <28 weeks' gestation) or extremely low birth weight (ELBW: <1000 g). Design Prospective cohort study. Setting State of Victoria, Australia. Patients 211 infants born EP/ELBW assessed at 2 years' corrected age (mean 2.2, SD 0.2). Main outcome measures Cognitive and language delay (<-1 SD) on the Bayley-III. The screening questionnaires were the Parent Report of Children's Abilities-Revised (PARCA-R) and the Ages & Stages Questionnaires Third Edition (ASQ-3). Results The PARCA-R performed better than the ASQ-3, but neither questionnaire had substantial agreement with the Bayley-III to detect cognitive delay; kappa (95% CI): PARCA-R 0.43 (0.23, 0.63); ASQ-3 0.15 (-0.05, 0.35); sensitivity (95% CI): PARCA-R 70% (53%, 84%) ASQ-3 62% (47%, 76%); specificity (95% CI): PARCA-R 73% (60%, 84%) ASQ-3 53% (38%, 68%). When both tools were used in combination (below cut-off on at least one assessment), sensitivity increased to 78% (60%, 91%) but specificity fell to 45% (29%, 62%). Similar trends were noted for language delay on the Bayley-III, although kappa values were better than for cognitive delay. Conclusions Neither screening questionnaire identified cognitive delay well, but both were better at identifying language delay. The PARCA-R detects delay on the Bayley-III more accurately than the ASQ-3. Sensitivity for detecting delay is greatest when the PARCA-R and ASQ-3 were used in combination, but resulted in lower specificity.

Introduction: Allergic sensitisation and lower respiratory tract infection (LRTI) during the first years of life are associated with adverse in lung function in school age children but their effect on preschool lung function remains poorly understood. Aim: To estimate the effect of allergic sensitisation and LRTI in the first year of life on gas mixing properties of the lung at age 4 years. Methods: Data were from the Barwon Infant Study, a birth cohort study of 1074 infants from the Barwon region of Victoria, Australia. Participants completed skin prick testing for allergic sensitisation at age 1 year, questionnaires on respiratory illness between birth and age 2 years and nitrogen multiple breath washout (N2MBW) assessment at 4 years of age. Outcomes were lung clearance index (LCI) and functional residual capacity (FRC). Differences in mean for LCI and FRC between respiratory illness and sensitisation groups were estimated using linear regression, with adjustment for confounding. Results: N2MBW data were available in 284 children at age 4 years. Allergic sensitisation at 1 year of age was associated with higher LCI at 4 years of age (Mean difference [MD], 95% confidence interval [CI]: 0.26, 0.00, 0.53). This effect was greater among children who experienced LRTI (MD, 95% CI: 0.32, 0.08, 0.57). LCI was similar between those with and without LRTI (MD, 95% CI: 0.05, -0.07 to 0.17). Conclusion: At 4 years of age, allergic sensitisation in infancy was associated with greater ventilation inhomogeneity, and this effect was more pronounced in children who also had LRTI during infancy. There was no evidence LRTI alone impacted subsequent lung function.

Abstract: Purpose: Providing specialised training to community-based physical activity instructors (such as circus coaches) has been identified as a potential strategy to increase participation for preschool-aged children born preterm. The objective of this study was to determine the feasibility of a novel co-designed training program CirqAll: professional development for circus coaches (CirqAll:PD), which aimed to increase coaches knowledge, skills, and confidence in working with children born preterm. Materials and methods: CirqAll:PD consisted of 10-hours of online self-directed content and four 90-minute online workshops completed over four weeks. Recruitment capability, acceptability, implementation fidelity and limited efficacy testing were evaluated using a case series design. Results: Fifty-one circus coaches were enrolled, and 27 completed CirqAll:PD. Reasons for attrition were primarily related to the Theoretical Framework of Acceptability s (TFA) concept of burden. All 27 coaches indicated that CirqAll:PD was acceptable (TFA questionnaire). Overall intervention fidelity was high (high adherence to planned delivery, moderate adherence to dosage, and excellent participant responsiveness). Limited efficacy testing revealed positive trends regarding coaches knowledge, skills, and confidence (Determinants of Implementation Behaviour Questionnaire). Conclusions: These results support the feasibility of CirqAll:PD. Adaptations to reduce attrition and burden on participants are required prior to further testing.

Objectives To compare health-related quality of life (HRQoL) at 25 and 18 years in individuals born extremely preterm (EP, <28 weeks' gestation) or with extremely low birth weight (ELBW, birth weight <1000 g) with term-born (=37 weeks) controls. Within the EP/ELBW cohort, to determine whether HRQoL differed between those with lower and higher IQs.Methods HRQoL was self-reported using the Health Utilities Index Mark 3 (HUI3) at 18 and 25 years by 297 EP/ELBW and 251 controls born in 1991-1992 in Victoria, Australia. Median differences (MDs) between groups were estimated using multiple imputation to handle missing data.Results Adults born EP/ELBW had lower HRQoL (median utility 0.89) at 25 years than controls (median utility 0.93, MD -0.040), but with substantial uncertainty in the estimate (95% CI -0.088 to 0.008) and a smaller reduction at 18 years (MD -0.016, 95% CI -0.061 to 0.029). On individual HUI3 items, there was suboptimal performance on speech (OR 9.28, 95% CI 3.09 to 27.93) and dexterity (OR 5.44, 95% CI 1.04 to 28.45) in the EP/ELBW cohort. Within the EP/ELBW cohort, individuals with lower IQ had lower HRQoL compared with those with higher IQ at 25 (MD -0.031, 95% CI -0.126 to 0.064) and 18 years (MD -0.034, 95% CI -0.107 to 0.040), but again with substantial uncertainty in the estimates.Conclusions Compared with term-born controls, young adults born EP/ELBW reported poorer HRQoL, as did those with lower IQ compared with those with higher IQ in the EP/ELBW cohort. Given the uncertainties, our findings need corroboration.

Background Few studies have tracked growth in children born extremely preterm (EP, <28 weeks' gestation) beyond late adolescence. The relationships between growth parameters (including weight and BMI) through childhood and adolescence with later cardiometabolic health, are unclear in those born EP. We aimed to (i) compare growth from 2 to 25 years between EP and controls; and in the EP group (ii) determine the associations of growth parameters with cardiometabolic health.Methods Prospective state-wide cohort of all EP livebirths in Victoria, Australia, in 1991-1992 and contemporaneous term-born controls. Z-scores for weight (z-weight), height (z-height) and BMI (z-BMI) at 2, 5, 8,18 and 25 years, and cardiometabolic health at 25 years (body composition, glucose tolerance, lipid profiles, blood pressure, exercise capacity) were measured. Growth trajectories were compared between groups using mixed models. The relationships between z-BMI changes/year, and being overweight at different ages, with cardiometabolic health were explored using linear regression.Findings Z-weight and z-BMI were lower in EP than controls, but the gap decreased with age due to a more rapid rate of rise in z-weight and a decrease in z-height in the EP group compared with controls. Greater increases in z-BMI/ year in the EP group were associated with poorer cardiometabolic health [coefficient (95% CI) per 0.1 z-BMI increase/ year: visceral fat volume (cm3) 217.8 (160.9, 274.7), triglycerides (mmol/L) 0.45 (0.20, 0.71), systolic blood pressure (mmHg) 8.9 (5.8, 12.0), and exercise capacity (BEEP test maximum level -1.2 (-1.7,-0.7)), all p < 0.001]. The association between being overweight with poorer cardiometabolic health strengthened with age.Interpretation The catch-up in weight and BMI by young adulthood in survivors born EP may not be desirable as it is associated with poorer cardiometabolic health. The associations of being overweight from mid-childhood with poorer cardiometabolic health may provide a window for intervention.Funding National Health and Medical Research Council of Australia.Copyright & COPY; 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).