OBJECTIVE:To evaluate the association between not passing newborn hearing screening and language, cognitive, and behavioral outcomes at 2 years' corrected age among infants born extremely preterm. STUDY DESIGN:Retrospective cohort study of infants born at 22-26 weeks of gestation or 401-1000 g at Neonatal Research Network centers from 2012-2021 who completed predischarge newborn hearing screening and neurodevelopmental follow-up at 22-26 months' corrected age. Mixed-effects models estimated associations between screening result and Bayley Language and Cognitive Composite scores and Child Behavior Checklist (CBCL) Total Problems T-scores, with secondary analyses of clinically relevant Bayley and CBCL thresholds after adjustment for center and clinical and sociodemographic covariates. RESULTS:Among 4891 infants, 690 (14%) did not pass newborn hearing screening. Compared with infants who passed, those who did not pass had modestly lower Bayley language (adjusted mean difference, -2.6; 95% CI, -4.1 to -1.1) and cognitive (adjusted mean difference, -2.4; 95% CI, -3.7 to -1.1) scores. They also had higher odds of Bayley language score <85 (aOR, 1.4; 95% CI, 1.1 to 1.7) and cognitive score <85 (aOR, 1.4; 95% CI, 1.1 to 1.7), but not of scores <70. Screening result was not independently associated with CBCL Total Problems T-score or with CBCL Total Problems T-score ≥60 or ≥64, although exploratory mediation analyses suggested small indirect associations through lower Bayley scores. In a small exploratory subgroup of infants who did not pass screening but had a normal inpatient diagnostic auditory brainstem response before discharge (n = 119), adjusted Bayley language and cognitive scores were also lower than among infants who passed screening. CONCLUSIONS:Among extremely preterm infants, not passing newborn hearing screening was associated with modestly lower language and cognitive performance at 2 years, particularly in the mild-to-moderate range, but not with early behavioral problems. These findings support prompt audiologic follow-up and developmental surveillance.

Importance Previous studies suggest that administration of erythropoiesis-stimulating agents darbepoetin or erythropoietin to preterm infants results in fewer transfusions, fewer donor exposures, and improved neurodevelopmental outcome. Objective To determine if, compared with placebo, preterm infants randomized to weekly darbepoetin would have greater red cell mass during hospitalization and better neurocognitive outcome at 22 to 26 months' corrected age. Design, Setting, and Participants This randomized clinical trial was conducted between September 2017 and November 2019 for infants 23 0/7 to 28 6/7 weeks' gestation in 19 US Neonatal Research Network centers comprising 33 neonatal intensive care units. Follow-up occurred through January 2023. Infants were randomized by 36 hours after birth to weekly placebo or darbepoetin (10 mu g/kg) through 35 weeks' postmenstrual age. Iron administration and transfusions were administered by protocol. Study data were analyzed from June to October 2023. Main Outcomes and MeasuresThe primary outcome was the mean cognitive composite score on the Bayley Scales of Infant Development, third edition (Bayley-III) at 22 to 26 months' corrected age. The lowest possible score (54) was assigned to infants who died. Results A total of 650 infants (322 darbepoetin; 328 placebo; mean [SD] gestational age, 26.2 [1.7] weeks; 328 female [50.5%]) were enrolled. Five hundred eighty-three infants (291 darbepoetin; 292 placebo) had the primary outcome determined (90% of those enrolled). Mean (SD) cognitive scores were similar between groups: 80.7 (19.5) darbepoetin vs 80.1 (18.7) placebo, adjusted mean difference, -0.23 (95% CI, -3.09 to 2.64). Compared with infants receiving placebo, more infants in the darbepoetin group were transfusion free (40% [127 of 319] vs 21% [70 of 327]; adjusted relative risk [RR], 1.3; 95% CI, 1.2-1.5), received fewer transfusions (mean [SD], 2.3 [3.1] vs 3.3 [3.5]), were exposed to fewer donors (mean [SD], 1.6 [2.3] vs 2.2 [2.3]), had higher red cell mass by week 2 of age (adjusted mean difference, 3.2; 95% CI, 1.7-4.7), and higher mean hematocrit by week 2 of age (adjusted mean difference, 2.8; 95% CI, 2.1-3.6), and were less likely to have bronchopulmonary dysplasia greater than grade 1 (35% [91 of 261] vs 46% [128 of 277]; RR, 0.78; 95% CI, 0.64-0.96). The incidence of retinopathy of prematurity stage greater than 2 was similar between groups, 13% (35 of 273) in the darbepoetin group vs 16% (45 of 279) in the placebo group. There were no differences in adverse effects between groups. Conclusions and Relevance Results of this randomized clinical trial reveal that this dose and dosing schedule of darbepoetin did not improve cognitive scores of preterm infants at 22 to 26 months' corrected age. Darbepoetin significantly increased red cell mass resulting in higher hematocrit values, fewer transfusions, and fewer donor exposures.

Previous studies suggest that administration of erythropoiesis-stimulating agents darbepoetin or erythropoietin to preterm infants results in fewer transfusions, fewer donor exposures, and improved neurodevelopmental outcome. To determine if, compared with placebo, preterm infants randomized to weekly darbepoetin would have greater red cell mass during hospitalization and better neurocognitive outcome at 22 to 26 months’ corrected age. This randomized clinical trial was conducted between September 2017 and November 2019 for infants 23 0/7 to 28 6/7 weeks’ gestation in 19 US Neonatal Research Network centers comprising 33 neonatal intensive care units. Follow-up occurred through January 2023. Infants were randomized by 36 hours after birth to weekly placebo or darbepoetin (10 μg/kg) through 35 weeks’ postmenstrual age. Iron administration and transfusions were administered by protocol. Study data were analyzed from June to October 2023. The primary outcome was the mean cognitive composite score on the Bayley Scales of Infant Development, third edition (Bayley-III) at 22 to 26 months’ corrected age. The lowest possible score (54) was assigned to infants who died. A total of 650 infants (322 darbepoetin; 328 placebo; mean [SD] gestational age, 26.2 [1.7] weeks; 328 female [50.5%]) were enrolled. Five hundred eighty-three infants (291 darbepoetin; 292 placebo) had the primary outcome determined (90% of those enrolled). Mean (SD) cognitive scores were similar between groups: 80.7 (19.5) darbepoetin vs 80.1 (18.7) placebo, adjusted mean difference, −0.23 (95% CI, −3.09 to 2.64). Compared with infants receiving placebo, more infants in the darbepoetin group were transfusion free (40% [127 of 319] vs 21% [70 of 327]; adjusted relative risk [RR], 1.3; 95% CI, 1.2-1.5), received fewer transfusions (mean [SD], 2.3 [3.1] vs 3.3 [3.5]), were exposed to fewer donors (mean [SD], 1.6 [2.3] vs 2.2 [2.3]), had higher red cell mass by week 2 of age (adjusted mean difference, 3.2; 95% CI, 1.7-4.7), and higher mean hematocrit by week 2 of age (adjusted mean difference, 2.8; 95% CI, 2.1-3.6), and were less likely to have bronchopulmonary dysplasia greater than grade 1 (35% [91 of 261] vs 46% [128 of 277]; RR, 0.78; 95% CI, 0.64-0.96). The incidence of retinopathy of prematurity stage greater than 2 was similar between groups, 13% (35 of 273) in the darbepoetin group vs 16% (45 of 279) in the placebo group. There were no differences in adverse effects between groups. Results of this randomized clinical trial reveal that this dose and dosing schedule of darbepoetin did not improve cognitive scores of preterm infants at 22 to 26 months’ corrected age. Darbepoetin significantly increased red cell mass resulting in higher hematocrit values, fewer transfusions, and fewer donor exposures. ClinicalTrials.gov Identifier: NCT03169881

Alcohol use remains common in pregnancy with prenatal alcohol exposure (PAE) associated with a plethora of adverse outcomes, including impaired emotional regulation and stress reactivity. Prior preclinical studies and emerging clinical evidence indicate that PAE affects the fetal hypothalamic–pituitary–adrenal (HPA) axis via the maternal‐fetal interface in the placenta; however, little is known about the effect of these alterations on neurodevelopmental outcomes. We earlier reported on the effect of PAE and maternal stress on HPA axis biomarkers in placenta and umbilical cord (UC) blood; in the current study, we examined the effect of HPA axis biomarkers on infant neurodevelopmental outcomes at 6–9 months of term‐equivalent age. Participants in the Ethanol, Neurodevelopment, Infant and Child Health (ENRICH‐2) prospective cohort were followed from the second trimester of pregnancy until infants were 6–9 months of term‐equivalent age. Maternal alcohol use was assessed through prospective interviews and a battery of ethanol biomarkers; maternal stress, by a Perceived Stress Scale (PSS). Placenta and UC blood specimens were collected shortly after birth, flash frozen, and analyzed for mRNA and protein expression of placental corticotropin‐releasing hormone (pCRH), hydroxysteroid 11‐beta dehydrogenase types 1 and 2 ( HSD11B1, HSD11B2 ) and corresponding proteins (11β‐HSD1 and 11β‐HSD2), and Nuclear receptor subfamily 3 Group C Member 1—alpha ( NR3C1‐α ) and corresponding glucocorticoid receptor alpha. UC plasma cortisol and cortisone levels were measured with ELISA. Bayley Scales of Infant Development, fourth edition (BSID‐4; Motor, Language, Cognitive scores) and Infant Behavior Questionnaire Revised (IBQ‐R; Surgency, Orienting/Regulation, Negative Affect) assessed neurodevelopment at 6–9 months of term‐equivalent age. Pearson correlation was used to examine associations between placental HPA axis biomarkers and neurodevelopmental outcomes overall and after stratification by group (Alcohol/Control). Multivariable linear regression assessed the independent effect of placental biomarkers and Alcohol * biomarker interactions on infant outcomes after adjusting for Alcohol and maternal stress. Participants (32 Alcohol and 68 Controls) were comparable in sociodemographic characteristics. Activation of the placental HPA axis was correlated with a decrease in BSID‐4 scores among Controls and an increase in IBQ‐R scores (Surgency and Negative Affect) among Alcohol participants. In multivariable analyses, the HSD11B2/HSD11B1 ratio was associated with a decrease in Cognitive scores, and the Alcohol * pCRH interaction was associated with a decrease in Orienting/Regulation and an increase in Surgency and Negative Affect (all p 's < .05), after adjusting for Alcohol and PSS. A significant independent effect of PSS was also observed on infant motor skills, Orienting/Regulation, and Negative Affect. This is the first clinical study to characterize the role of placental HPA axis biomarkers and maternal psychosocial stress in PAE‐induced changes on infant neurodevelopment, highlighting the importance of a “placenta–brain axis”. We demonstrated that the effects of mild‐to‐moderate PAE on infant neurobehavior were observed in participants with the highest quartile of pCRH expression, emphasizing the role of placental biomarkers in PAE‐induced effects.

BACKGROUND:Bronchopulmonary dysplasia (BPD) affects up to half of extremely preterm infants, and is associated with adverse long-term respiratory, neurodevelopmental, and educational sequelae and costly health service and family economic outcomes. The NICHD Neonatal Research Network Hydrocortisone for Bronchopulmonary Dysplasia (BPD) Trial evaluated the efficacy and safety of hydrocortisone treatment to prevent BPD in high-risk infants. The trial enrolled 800 very preterm infants with respiratory failure and followed the participants until 2 years corrected age to assess safety of the trial intervention. Longer-term impacts of hydrocortisone exposure and severity of BPD on functional outcomes of high-risk infants remain unknown. The HYdrocortisone for BPD Respiratory and Developmental (HYBRiD) Outcomes Study extends follow-up of all surviving children enrolled in the Hydrocortisone for BPD Trial until early school age. It aims to characterize the childhood functional motor, cognitive, academic, and pulmonary outcomes of this large, well-phenotyped trial cohort. METHODS:Parents of surviving trial participants complete telephone questionnaires when their children are 3 and 4 years corrected age. A single in-person study visit takes place at early school age (5 years, 0 months to 7 years, 11 months corrected age). Children undergo a multidimensional assessment of functional outcomes and parents complete a battery of questionnaires. In 5 of 19 participating centers, respiratory mechanics are evaluated with impulse oscillometry. DISCUSSION:The HYBRiD Outcomes Study will be the largest and most comprehensive evaluation to date of the functional early school age outcomes of children with a history of severe neonatal lung disease and of children exposed to HC during infancy. This will substantially improve understanding of the longer-term implications of severe neonatal lung disease; provide data to facilitate the development of future randomized intervention trials in this population; and inform public policy by enhancing knowledge about school age resource requirements in children with a history of prematurity and lung disease. TRIAL REGISTRATION:clinicaltrials.gov ID NCT01353313. Primary trial registration 5/11/11 modified to include followup through school age 12/13/17. This manuscript reflects version 3 of the trial manuscript, dated 10/12/2020.

Objective: We previously reported improved neurodevelopment at 2 and 4 years among preterm infants treated with erythropoietin or darbepoetin, known as erythropoiesis-stimulating agents (ESAs). We now characterize longitudinal outcomes through 6 years. Methods: Children randomized to ESAs or placebo were evaluated at 6 years. Healthy-term chil-dren served as controls. Tests of cognition and executive function (EF) were performed. Results: Cognitive/EF scores remained similar between 4 and 6 years within each group (ESA: 43 children; placebo: 17 children; term: 21 children). ESA recipients scored higher than placebo on Full-Scale IQ (94.2 ± 18.6 vs. 81.6 ± 16.7, p = 0.022), and Performance IQ (97.3 ± 16.2 vs. 81.7 ± 15.2, = 0.005). Aggregate EF trended better for the ESA group. Term controls scored better than placebo on all measures. ESA and term controls scored similarly on cognitive and EF tests. Conclusions: ESA recipients had better outcomes than placebo recipients, and were similar to term children. ESAs may improve long-term cognition and executive function in preterm infants.

OBJECTIVE:To determine the ability of the Bayley-III cognitive and language composite scores at 18-22 months corrected age to predict WISC-IV Full Scale IQ (FSIQ) at 6-7 years in infants born extremely preterm. STUDY DESIGN:Children in this study were part of the Neuroimaging and Neurodevelopmental Outcome cohort, a secondary study to the SUPPORT trial and born 240/7-276/7 weeks gestational age. Bayley-III cognitive and language scores and WISC-IV FSIQ were compared with pairwise Pearson correlation coefficients and adjusted for medical and socioeconomic variables using linear mixed effect regression models. RESULTS:Bayley-III cognitive (r = 0.33) and language scores (r = 0.44) were mildly correlated with WISC-IV FSIQ score. Of the children with Bayley-III cognitive scores of <70, 67% also had FSIQ of <70. There was less consistency for children with Bayley-III scores in the 85-100 range; 43% had an FSIQ of <85 and 10% an FSIQ of <70. Among those with Bayley-III language scores >100, approximately 1 in 5 had an FSIQ of <85. A cut point of 92 for the cognitive composite score resulted in sensitivity (0.60), specificity (0.64). A cut point of 88 for the language composite score produced sensitivity (0.61), specificity (0.70). CONCLUSIONS:Findings indicate the Bayley-III cognitive and language scores correlate with later IQ, but may fail to predict delay or misclassify children who are not delayed at school age. The Bayley-III can be a useful tool to help identify children born extremely preterm who have below average cognitive scores and may be at the greatest risk for ongoing cognitive difficulties. TRIAL REGISTRATION:Extended Follow-up at School Age for the SUPPORT Neuroimaging and Neurodevelopmental Outcomes (NEURO) Cohort: NCT00233324.

Objectives To compare serum ferritin and RET-He values among extremely low gestational age neonates ELGANs with other markers of iron-deficient erythropoiesis. Study Design This is a secondary analysis of the NICHD Darbepoetin Trial. Study data from placebo recipients who had a serum ferritin, a RET-He, and a mean corpuscular volume (MCV) measurement within a 24-hour period were analyzed for correlation. Results Mixed linear regression models showed no association between ferritin and RET-He at both early ( β = 0.0016, p = 0.40) and late ( β = −0.0001, p = 0.96) time points. Positive associations were observed between RET-He and MCV at baseline, early, and late time points ( p < 0.01, =0.01, <0.001, respectively), while ferritin was not associated with MCV at any time point. Conclusions Our study shows that RET-He is better correlated with MCV as a marker of iron-limited erythropoiesis than ferritin. The results suggest that ferritin is limited as a marker of iron sufficiency in premature infants. Study Identification FDA IND Number 100138; ClinicalTrials.gov number NCT03169881; NRN ID number NICHD-NRN-0058 (Darbe).

With significant increases in opioid use/misuse and persistent high prevalence of prenatal alcohol exposure (PAE), identifying infants at risk for long-term developmental sequelae due to these exposures remains an urgent need. This study reports on developmental outcomes in young children from a prospective cohort, ENRICH-1, which recruited pregnant women and followed up maternal–infant pairs. Subjects were assigned to four study groups based on prenatal use of medications for opioid use disorder (MOUD), PAE, MOUD+PAE, and unexposed controls (UC). Mixed effects modeling was used to evaluate changes in the Bayley Scales of Infant Development-III (BSID-III) Cognitive, Language, and Motor scores between 6 and 20 months. There was a significant three-way interaction (MOUD-by-PAE-by-Time) with respect to the BSID-III Cognitive (p = 0.045) and Motor (p = 0.033) scales. Significant changes between the two evaluations were observed for MOUD group in Cognitive and Language scores; for PAE group in Cognitive, Language, and Motor scores, and for MOUD+PAE group in Language scores after adjusting for child sex and family socio-economic status. The developmental scores for the UC remained stable. Observed decline in neurodevelopmental scores during the first 2 years of life emphasizes the importance of a longitudinal approach when evaluating children with prenatal polysubstance exposure.

Stress regulation begins to develop in the first year of life through interactions with caregivers, particularly in the presence of stressors. High quality caregiving, characterized by maternal sensitivity and responsiveness to the infant's emotional cues, is particularly important in the development of infant stress regulation. The purpose of this study was to assess the longitudinal stability of, and associations between, maternal interactive behavior and infant stress regulation (indexed by positive infant affect and cortisol reactivity) in response to the Still Face paradigm (SF) in a cohort of infants born preterm (< 32 weeks gestation, N = 22) at four months and nine months (adjusted age). The percent of time mothers spent using specific interaction styles (contingent maternal interaction (CMI), attention seeking, and watching) during Play/baseline, Reunion#1, and Reunion#2 SF episodes was calculated To assess infant stress regulation, two indices were obtained at both 4 and 9 months during the SF paradigm: the percent of positive affect displayed over each SF episode (0-100%) and a neuroendocrine stress response score based on salivary cortisol reactivity. We found three non-significant but medium-large effect size differences between 4 and 9 month variables, with more positive findings at 9 months. Regarding stability within the 4 month and 9 month episodes, maternal behavior and positive infant affect were non-significantly but moderately stable, with maternal watching behavior being particularly stable. Positive infant affect stability between Reunion#1 and Reunion#2 at 4 months was significantly greater than positive infant affect stability across these two episodes at 9 months. Regarding stability across 4 and 9 month (same) episodes, CMI and positive infant affect showed modest but non-significant stability across (same) 4 and 9 month episodes. Finally, with positive infant affect at Reunion#2 as the "outcome" of the Still Face, CMI at both 4 month Play and Reunion#1 episodes were significantly correlated with this "outcome." Further, positive infant affect at Reunion#2 was more strongly correlated with CMI at both Play and Reunion#1 for 4 month old compared with 9 month old infants. Thus, sensitive care appears particularly important for younger infants born preterm, and mothers' behavior early in a repeated stress exposure paradigm may be particularly important in maintaining positive infant affect and in the development of infants' stress regulation more generally. Identifying the longer-term effects of early stress on infant stress regulation, and its relationship with maternal interaction, has important implications for understanding trajectories of regulatory patterns and deficits. A greater understanding of these relationships is particularly important given that greater emotion and neuroendocrine stress regulation in infancy have been directly associated with numerous positive outcomes throughout childhood.

BACKGROUND Neonatal hypoxic-ischemic encephalopathy is an important cause of death as well as long-term disability in survivors. Erythropoietin has been hypothesized to have neuroprotective effects in infants with hypoxic-ischemic encephalopathy, but its effects on neurodevelopmental outcomes when given in conjunction with therapeutic hypothermia are unknown. METHODS In a multicenter, double-blind, randomized, placebo-controlled trial, we assigned 501 infants born at 36 weeks or more of gestation with moderate or severe hypoxic-ischemic encephalopathy to receive erythropoietin or placebo, in conjunction with standard therapeutic hypothermia. Erythropoietin (1000 U per kilogram of body weight) or saline placebo was administered intravenously within 26 hours after birth, as well as at 2, 3, 4, and 7 days of age. The primary outcome was death or neurodevelopmental impairment at 22 to 36 months of age. Neurodevelopmental impairment was defined as cerebral palsy, a Gross Motor Function Classification System level of at least 1 (on a scale of 0 [normal] to 5 [most impaired]), or a cognitive score of less than 90 (which corresponds to 0.67 SD below the mean, with higher scores indicating better performance) on the Bayley Scales of Infant and Toddler Development, third edition. RESULTS Of 500 infants in the modified intention-to-treat analysis, 257 received erythropoietin and 243 received placebo. The incidence of death or neurodevelopmental impairment was 52.5% in the erythropoietin group and 49.5% in the placebo group (relative risk, 1.03; 95% confidence interval [CI], 0.86 to 1.24; P = 0.74). The mean number of serious adverse events per child was higher in the erythropoietin group than in the placebo group (0.86 vs. 0.67; relative risk, 1.26; 95% CI, 1.01 to 1.57). CONCLUSIONS The administration of erythropoietin to newborns undergoing therapeutic hypothermia for hypoxic-ischemic encephalopathy did not result in a lower risk of death or neurodevelopmental impairment than placebo and was associated with a higher rate of serious adverse events. (Funded by the National Institute of Neurological Disorders and Stroke; ClinicalTrials.gov number, NCT02811263.).

Background Extremely preterm (EPT) birth has been related to dysregulation of stress responses and behavioral/learning problems at school age. Early adverse experiences can blunt HPA axis reactivity. We hypothesized that an attenuated cortisol awakening response would be associated with developmental and behavioral problems at school age in EPT children. Methods This secondary analysis of a sub-cohort of the SUPPORT study included children born between 24 and 27 weeks, evaluated at 6–7 years with a neurodevelopmental battery and cortisol measures. Differences were tested between EPT and a term-born group. Relationships of cortisol awakening response to test scores were analyzed. Results Cortisol was measured in 110 EPT and 29 term-born 6–7 year olds. Unadjusted WISC-IV and NEPSY-II scores were significantly worse among EPT children only. Conners Parent Rating Scale behavior scores were significantly worse among EPT children. After adjusting for covariates, blunted cortisol awakening responses were found to be associated with poorer scores on memory tests and greater problems with inattention for the EPT group ( p < 0.05) only. Conclusions Among children born EPT, we identified an association of blunted cortisol awakening response with memory and inattention problems. This may have implications related to stress reactivity and its relationship to learning problems in children born EPT. ClinicalTrials.gov ID Extended Follow-up at School Age for the SUPPORT Neuroimaging and Neurodevelopmental Outcomes (NEURO) Cohort: NCT00233324. Impact In children born EPT, stress reactivity may have a relationship to learning problems. Cortisol awakening response should be a component for follow-up in EPT born children. Components of executive function, such as memory and attention, are related to stress reactivity.

BACKGROUND Bronchopulmonary dysplasia is a prevalent complication after extremely preterm birth. Inflammation with mechanical ventilation may contribute to its development. Whether hydrocortisone treatment after the second postnatal week can improve survival without bronchopulmonary dysplasia and without adverse neurodevelopmental effects is unknown. METHODS We conducted a trial involving infants who had a gestational age of less than 30 weeks and who had been intubated for at least 7 days at 14 to 28 days. Infants were randomly assigned to receive either hydrocortisone (4 mg per kilogram of body weight per day tapered over a period of 10 days) or placebo. Mandatory extubation thresholds were specified. The primary efficacy outcome was survival without moderate or severe bronchopulmonary dysplasia at 36 weeks of postmenstrual age, and the primary safety outcome was survival without moderate or severe neurodevelopmental impairment at 22 to 26 months of corrected age. RESULTS We enrolled 800 infants (mean [+/- SD] birth weight, 715 +/- 167 g; mean gestational age, 24.9 +/- 1.5 weeks). Survival without moderate or severe bronchopulmonary dysplasia at 36 weeks occurred in 66 of 398 infants (16.6%) in the hydrocortisone group and in 53 of 402 (13.2%) in the placebo group (adjusted rate ratio, 1.27; 95% confidence interval [CI], 0.93 to 1.74). Two-year outcomes were known for 91.0% of the infants. Survival without moderate or severe neurodevelopmental impairment occurred in 132 of 358 infants (36.9%) in the hydrocortisone group and in 134 of 359 (37.3%) in the placebo group (adjusted rate ratio, 0.98; 95% CI, 0.81 to 1.18). Hypertension that was treated with medication occurred more frequently with hydrocortisone than with placebo (4.3% vs. 1.0%). Other adverse events were similar in the two groups. CONCLUSIONS In this trial involving preterm infants, hydrocortisone treatment starting on postnatal day 14 to 28 did not result in substantially higher survival without moderate or severe bronchopulmonary dysplasia than placebo. Survival without moderate or severe neurodevelopmental impairment did not differ substantially between the two groups.

Introduction: Return to play protocols (RTP) are imperative to ensuring injured athletes are adequately prepared to return to competition without re-injury. This study aimed to characterise the acute and chronic external workloads achieved by injured National Rugby League (NRL) athletes before and after RTP. Methods: Global positioning system (GPS) workload variables were investigated for 10 injured NRL athletes (n= 10, mean age 23.6 years, backs n=5, forwards n=5) two weeks before and after RTP. All athletes had sustained injuries of ≥14-day severity. GPS variables included total (TD) and high to very-high speed running (V-VHSR) distance (≥18km/h), accumulated absolute acceleration (acceleration load), and number of repeat high-intensity efforts (RHIE). Both acute (current week) and chronic (4-week mean) workload was determined for each observation week and analysed using linear mixed models that included time as a fixed effect, mean-centred injury severity as a covariate, and participant as a random effect. Effect magnitude was determined by percentage difference and 95% confidence interval. Results: Mean injury severity was 24 days (range: 14-49 days) and did not significantly moderate any acute (p≥0.614) or chronic (p≥0.272) workload variable. Time significantly affected acute TD, acceleration load, and RHIE (p≤0.038), but not VVHSR distance (p=0.070). Acute workload was highest during the week of RTP for all variables, with an 86 ±51% (TD), 41 ±37% (V-VHSR), 95 ±50% (acceleration load), and 116 ±72% (RHIE) increase compared to the previous rehabilitation week. Time significantly affected chronic RHIE (p=0.038), but not TD (p=0.315), V-VHSR (p=0.931), or acceleration load (p=0.213). Chronic workload was highest during the second week after RTP, with the three previous weeks being decreased by -13 to 17 ±18% (TD), -7 to -8 ±24% (V-VHSR), -14 to -18 ±17% (acceleration load), and -22 to -28 ±19% (RHIE). Discussion: The acute external workloads of injured NRL athletes demonstrated large increases during the RTP week which may increase the likelihood of re-injury. In contrast, chronic workload was relatively stable before and after RTP for all external workload variables except RHIE which was low until 2 weeks after RTP. Greater focus on RHIE workload in the lead up to RTP may be needed to ensure adequate exposure to that aspect of rugby league. Conflict of interest statement: my co-authors and I acknowledge that we have no conflict of interest of relevance to the submission of this abstract.