Cognitive Development and Quality of Life Associated With BPD in 10-Year-Olds Born Preterm

Continuous Neuromuscular Blockade for Bronchopulmonary Dysplasia

OBJECTIVE

 Bronchopulmonary dysplasia (BPD) is the most common late morbidity for premature infants. Continuous neuromuscular blockade (CNMB) is suggested for the most unstable phase of BPD, despite no outcome data. We explored the association between duration of CNMB for severe BPD and mortality.

DESIGN

 Medical record review of children <5 years old admitted from 2016 to 2022 with BPD and one or more course of CNMB for ≥14 days.

RESULTS

 Twelve children received a total of 20 episodes of CNMB for ≥14 days (range 14-173 d) during their hospitalization. Most (10/12) were born at <28 weeks' gestation and most (11/12) with birth weight <1,000 g; 7/12 were of Black race/ethnicity. All were hospitalized since birth. Most (10/12) were initially transferred from an outside neonatal intensive care unit (ICU), typically after a >60-day hospitalization (9/12). Half (6/12) of them had a ≥60-day stay in our neonatal ICU before transferring to our pediatric ICU for, generally, ≥90 days (8/12). The primary study outcome was survival to discharge: 2/12 survived. Both had shorter courses of CNMB (19 and 25 d); only one child who died had a course ≤25 days. Just two infants had increasing length Z-scores during hospitalization; only one infant had a final length Z-score > - 2.

CONCLUSION

 In this case series of infants with severe BPD, there were no survivors among those receiving ≥25 days of CNMB. Linear growth, an essential growth parameter for infants with BPD, decreased in most patients. These data do not support the use of ≥25 days of CNMB to prevent mortality in infants with severe BPD.

KEY POINTS

· This is a case series of neuromuscular blockade for severe BPD.. · Neuromuscular blockade did not improve linear growth.. · Ten out of 12 infants who were on prolonged neuromuscular blockade died..

Systemic steroids and bronchopulmonary dysplasia: a systematic review and meta-analysis

IMPORTANCE

It is unclear if systemic steroids decrease the risk of Bronchopulmonary Dysplasia (BPD) while increasing the risk of neurodevelopmental impairment (NDI).

OBJECTIVE

Conduct a systematic review of randomized controlled trials of systemic steroids to evaluate the risk of BPD, mortality, and NDI in premature infants ≤30 weeks.

DATA SOURCES

MEDLINE, EBSCOhost, Web of Science, Cochrane Library, Embase, and CINAHL.

STUDY SELECTION

Randomized clinical trials of Dexamethasone (DEX) or Hydrocortisone (HC) to prevent BPD in premature infants ≤ 30 weeks.

DATA EXTRACTION AND SYNTHESIS

Data were extracted using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Random-effects meta-analyses and multivariable meta-regression were conducted.

MAIN OUTCOMES AND MEASURES

Primary outcomes were BPD, mortality, and NDI. Secondary outcomes were hypertension, hyperglycemia, sepsis, intestinal perforation, necrotizing enterocolitis (NEC), and retinopathy of prematurity (ROP). The a priori hypothesis was that steroids would reduce the risk of BPD without increasing NDI.

RESULTS

There were 6377 preterm infants in the 44 (32 DEX, 13 HC) selected studies. DEX significantly reduced the risk of BPD, RR = 0.66, (95% CI, 0.56-0.78). The most effective DEX regimen was medium cumulative dose (2 to 3 mg/kg), RR = 0.43 (95% CI, 0.29-0.65); day of initiation <8 days: RR = 0.68, (95% CI, 0.59-0.79); and treatment for ≥14 days: RR = 0.67 (95% CI, 0.55-0.80). HC did not significantly decrease the risk of BPD, RR = 0.98, (95% CI, 0.87-1.10). Neither DEX, (RR = 0.92, 95% CI, 0.78-1.09) nor HC (RR = 0.83, 95% CI, 0.68-1.01) decrease the risk of mortality. The risk of CP was not increased by either DEX (RR = 1.09, 95% CI, 0.55-2.17) or HC (RR = 1.18, 95% CI, 0.75-1.87). There were no significant differences between steroids and placebo for MDI/PDI scores. Multivariable meta-regression models showed that DEX significantly reduced the risk of BPD without increased risk of CP. DEX increased the risk of hypertension and hyperglycemia. Studies showed high heterogeneity, differing treatment regimen, missing data and different rates of follow-up.

CONCLUSION AND RELEVANCE

DEX, but not HC, significantly decreased the risk of BPD. Neither steroid showed an increased risk of NDI or mortality.

A phase II, multicenter, nonblinded, randomized controlled trial for evaluating protective effects of ABPC/SBT plus, azithromycin versus erythromycin, in pregnant women with pPROM occurring at <28 weeks of gestation on the development of BPD in neonates: Study protocol

This is a protocol for PPROM-AZM Study, phase II, nonblinded, randomized controlled trial. Bronchopulmonary dysplasia (BPD) at a postmenstrual age of 36 weeks (BPD36) is often observed in infants with preterm premature rupture of the membranes (pPROM). A regimen of ampicillin (ABPC) intravenous infusion for 2 days and subsequent amoxicillin (AMPC) oral administration for 5 days plus erythromycin (EM) intravenous infusion for 2 days followed by EM oral administration for 5 days is standard treatment for pPROM. However, the effect on the prevention of moderate/severe BPD36 using the standard treatment has not been confirmed. Recently, it is reported that ampicillin/sulbactam (ABPC/SBT) plus azithromycin (AZM) was effective for the prevention of moderate/severe BPD36 in pPROM patients with amniotic infection of Ureaplasma species. Therefore, our aim is to evaluate the occurrence rate of the composite outcome of "incidence rate of either moderate/severe BPD36 or intrauterine fetal death, and infantile death at or less than 36 weeks 0 days" comparing subjects to receive ABPC/SBT for 14 days plus AZM for 14 days (intervention group) and those to receive ABPC/SBT for 14 days plus EM for 14 days (control group), in a total of 100 subjects (women with pPROM occurring at 22-27 weeks of gestation) in Japan. The recruit of subjects was started on April 2022, and collection in on-going. We also investigate the association between the detection of Ureaplasma species and occurrence of BPD36. In addition, information on any adverse events for the mother and fetus and serious adverse events for infants are collected during the observation period. We allocate patients at a rate of 1:1 considering two stratification factors: onset of pPROM (22-23 or 24-27 weeks) and presence/absence of a hospital policy for early neonatal administration of caffeine. Trial registration: The trial number in the Japan Registry of Clinical Trials is jRCTs031210631.

Childhood outcomes following discharge from a referral bronchopulmonary dysplasia program

OBJECTIVES

The primary objective of this study was to profile the childhood health, development, and health-related quality of life (HR QoL) for children with the most severe bronchopulmonary dysplasia (BPD), those discharged from a quaternary referral program.

STUDY DESIGN

We collected cross-sectional data through telephone interviews with 282 families of children ages 18 months to 11 years who had been discharged from a BPD referral program.

RESULTS

Respiratory morbidities were near universal, with 42% of children ever having required a tracheostomy and severity of these morbidities correlated with parent-reported health and QoL. Developmental morbidities were also marked: 97% required an individualized educational plan. While respiratory morbidities and overall health improved over time, developmental morbidities were increasingly prominent, resulting in lower quality of life.

CONCLUSIONS

Among children referred to a quaternary BPD program, respiratory and developmental morbidities are on numerous counts more severe than any reported in the literature.

Repeated intravenous doses of human umbilical cord-derived mesenchymal stromal cells for bronchopulmonary dysplasia: results of a phase 1 clinical trial with 2-year follow-up

BACKGROUND

Currently, there is a lack of effective treatments or preventive strategies for bronchopulmonary dysplasia (BPD). Pre-clinical studies with mesenchymal stromal cells (MSCs) have yielded encouraging results. The safety of administering repeated intravenous doses of umbilical cord tissue-derived mesenchymal stromal cells (UC-MSCs) has not yet been tested in extremely-low-gestational-age newborns (ELGANs).

AIMS

to test the safety and feasibility of administering three sequential intravenous doses of UC-MSCs every 7 days to ELGANs at risk of developing BPD.

METHODS

In this phase 1 clinical trial, we recruited ELGANs (birth weight ≤1250 g and ≤28 weeks in gestational age [GA]) who were on invasive mechanical ventilation (IMV) with FiO2 ≥ 0.3 at postnatal days 7-14. Three doses of 5 × 106/kg of UC-MSCs were intravenously administered at weekly intervals. Adverse effects and prematurity-related morbidities were recorded.

RESULTS

From April 2019 to July 2020, 10 patients were recruited with a mean GA of 25.2 ± 0.8 weeks and a mean birth weight of 659.8 ± 153.8 g. All patients received three intravenous UC-MSC doses. The first dose was administered at a mean of 16.6 ± 2.9 postnatal days. All patients were diagnosed with BPD. All patients were discharged from the hospital. No deaths or any serious adverse events related to the infusion of UC-MSCs were observed during administration, hospital stays or at 2-year follow-up.

CONCLUSIONS

The administration of repeated intravenous infusion of UC-MSCs in ELGANs at a high risk of developing BPD was feasible and safe in the short- and mid-term follow-up.

Mechanistic advances of hyperoxia-induced immature brain injury

The impact of hyperoxia-induced brain injury in preterm infants is being increasingly investigated. However, the parameters and protocols used to study this condition in animal models lack consistency. Research is further hampered by the fact that hyperoxia exerts both direct and indirect effects on oligodendrocytes and neurons, with the precise underlying mechanisms remaining unclear. In this article, we aim to provide a comprehensive overview of the conditions used to induce hyperoxia in animal models of immature brain injury. We discuss what is known regarding the mechanisms underlying hyperoxia-induced immature brain injury, focusing on the effects on oligodendrocytes and neurons, and briefly describe therapies that may counteract the effects of hyperoxia. We also identify further studies required to fully elucidate the effects of hyperoxia on the immature brain as well as discuss the leading therapeutic options.

Relationships of Severity of Bronchopulmonary Dysplasia with Adverse Neurodevelopmental Outcomes and Poor respiratory Function at 7-8 Years of Age

OBJECTIVE

To clarify the relationships of three definitions of severity of bronchopulmonary dysplasia (BPD) with adverse neurodevelopmental and respiratory outcomes at early school-age.

STUDY DESIGN

Participants 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.

RESULTS

Of 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.

CONCLUSIONS

Compared 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.

A review of the effects of early postnatal hyperoxia exposure on the immature brain

Preterm birth is a public health priority worldwide, with approximately 15 million premature babies born each year. Oxygen supplementation is one of the most common interventions for preterm infants. However, prolonged oxygen inhalation at supraphysiological concentrations can lead to the development of bronchopulmonary dysplasia (BPD). In addition to lifelong pulmonary sequelae, clinical evidence suggests that BPD is associated with adverse neurodevelopmental outcomes, such as motor impairment, cognitive impairment, and behavioral deficits, severely affecting the quality of life of preterm infants. However, the mechanisms underlying the combination of neurodevelopmental impairment with BPD remain unclear. Therefore, in recent years, attention has also been focused on the effects of hyperoxia on brain development in preterm infants. In this review, we outline the pathophysiological mechanisms of brain injury caused by developmental hyperoxia exposure in current animal models and briefly describe the pharmacological therapies that may be applicable to the associated brain injury. Overall, more studies are needed to assess the effects of hyperoxia on the immature brain, particularly combined analyses of the lungs and brain in the same experimental setting, to elucidate the potential causes of combined neurodevelopmental impairment in BPD.

Impact of bronchopulmonary dysplasia on brain GABA concentrations in preterm infants: Prospective cohort study

BACKGROUND

Bronchopulmonary dysplasia (BPD) is associated with cognitive-behavioral deficits in very preterm (VPT) infants, often in the absence of structural brain injury. Advanced GABA-editing techniques like Mescher-Garwood point resolved spectroscopy (MEGA-PRESS) can quantify in-vivo gamma-aminobutyric acid (GABA+, with macromolecules) and glutamate (Glx, with glutamine) concentrations to investigate for neurophysiologic perturbations in the developing brain of VPT infants.

OBJECTIVE

To investigate the relationship between the severity of BPD and basal-ganglia GABA+ and Glx concentrations in VPT infants.

METHODS

MRI studies were performed on a 3 T scanner in a cohort of VPT infants [born ≤32 weeks gestational age (GA)] without major structural brain injury and healthy-term infants (>37 weeks GA) at term-equivalent age. MEGA-PRESS (TE68ms, TR2000ms, 256averages) sequence was acquired from the right basal-ganglia voxel (∼3cm3) and metabolite concentrations were quantified in institutional units (i.u.). We stratified VPT infants into no/mild (grade 0/1) and moderate-severe (grade 2/3) BPD.

RESULTS

Reliable MEGA-PRESS data was available from 63 subjects: 29 healthy-term and 34 VPT infants without major structural brain injury. VPT infants with moderate-severe BPD (n = 20) had the lowest right basal-ganglia GABA+ (median 1.88 vs. 2.28 vs. 2.12 i.u., p = 0.025) and GABA+/choline (0.73 vs. 0.99 vs. 0.88, p = 0.004) in comparison to infants with no/mild BPD and healthy-term infants. The GABA+/Glx ratio was lower (0.34 vs. 0.44, p = 0.034) in VPT infants with moderate-severe BPD than in infants with no/mild BPD.

CONCLUSIONS

Reduced GABA+ and GABA+/Glx in VPT infants with moderate-severe BPD indicate neurophysiologic perturbations which could serve as early biomarkers of future cognitive deficits.

GSDMD gene knockout alleviates hyperoxia-induced hippocampal brain injury in neonatal mice

BACKGROUND

Neonatal hyperoxia exposure is associated with brain injury and poor neurodevelopment outcomes in preterm infants. Our previous studies in neonatal rodent models have shown that hyperoxia stimulates the brain's inflammasome pathway, leading to the activation of gasdermin D (GSDMD), a key executor of pyroptotic inflammatory cell death. Moreover, we found pharmacological inhibition of caspase-1, which blocks GSDMD activation, attenuates hyperoxia-induced brain injury in neonatal mice. We hypothesized that GSDMD plays a pathogenic role in hyperoxia-induced neonatal brain injury and that GSDMD gene knockout (KO) will alleviate hyperoxia-induced brain injury.

METHODS

Newborn GSDMD knockout mice and their wildtype (WT) littermates were randomized within 24 h after birth to be exposed to room air or hyperoxia (85% O2) from postnatal days 1 to 14. Hippocampal brain inflammatory injury was assessed in brain sections by immunohistology for allograft inflammatory factor 1 (AIF1) and CD68, markers of microglial activation. Cell proliferation was evaluated by Ki-67 staining, and cell death was determined by TUNEL assay. RNA sequencing of the hippocampus was performed to identify the transcriptional effects of hyperoxia and GSDMD-KO, and qRT-PCR was performed to confirm some of the significantly regulated genes.

RESULTS

Hyperoxia-exposed WT mice had increased microglia consistent with activation, which was associated with decreased cell proliferation and increased cell death in the hippocampal area. Conversely, hyperoxia-exposed GSDMD-KO mice exhibited considerable resistance to hyperoxia as O2 exposure did not increase AIF1 + , CD68 + , or TUNEL + cell numbers or decrease cell proliferation. Hyperoxia exposure differentially regulated 258 genes in WT and only 16 in GSDMD-KO mice compared to room air-exposed WT and GSDMD-KO, respectively. Gene set enrichment analysis showed that in the WT brain, hyperoxia differentially regulated genes associated with neuronal and vascular development and differentiation, axonogenesis, glial cell differentiation, hypoxia-induced factor 1 pathway, and neuronal growth factor pathways. These changes were prevented by GSDMD-KO.

CONCLUSIONS

GSDMD-KO alleviates hyperoxia-induced inflammatory injury, cell survival and death, and alterations of transcriptional gene expression of pathways involved in neuronal growth, development, and differentiation in the hippocampus of neonatal mice. This suggests that GSDMD plays a pathogenic role in preterm brain injury, and targeting GSDMD may be beneficial in preventing and treating brain injury and poor neurodevelopmental outcomes in preterm infants.

Validity and reliability of the behavioral signs of respiratory instability (BSRI) © scale during activity for infants with bronchopulmonary dysplasia

OBJECTIVE

There is no reliable evidence on how best to evaluate the overall status of infants with severe forms of bronchopulmonary dysplasia (BPD). The Behavioral Signs of Respiratory Instability (BSRI) scale was developed as an objective measure of developmental capacity during occupational and physical therapy sessions. The purpose of this study was to determine the psychometric properties of the BSRI Scale.

STUDY DESIGN

The BSRI and Respiratory Severity Score (RSS) were compared for 25 infants with BPD and 15 infants without BPD. A cross-sectional design was used to test inter-rater reliability among 10 NICU occupational and physical therapists. A prospective cohort design was used to evaluate validity.

RESULTS

The BSRI demonstrated good to excellent inter-rater reliability (ρ = 0.47-0.91) and was strongly correlated with RSS (ρ = -0.77, p < 0.001; concurrent validity).

CONCLUSION

The BSRI Scale has preliminary psychometric support. Standardized measures like the BSRI may provide accurate, objective data that can improve care planning within interdisciplinary teams that supports brain growth and potentially improves neurodevelopment.

GSDMD gene knockout alleviates hyperoxia-induced hippocampal brain injury in neonatal mice

Background: Neonatal hyperoxia exposure is associated with brain injury and poor neurodevelopment outcomes in preterm infants. Our previous studies in neonatal rodent models have shown that hyperoxia stimulates the brain's inflammasome pathway, leading to the activation of gasdermin D (GSDMD), a key executor of pyroptotic inflammatory cell death. Moreover, we found inhibition of GSDMD activation attenuates hyperoxia-induced brain injury in neonatal mice. We hypothesized that GSDMD plays a pathogenic role in hyperoxia-induced neonatal brain injury and that GSDMD gene knockout (KO) will alleviate hyperoxia-induced brain injury. Methods: Newborn GSDMD knockout mice and their wildtype (WT) littermates were randomized within 24 h after birth to be exposed to room air or hyperoxia (85% O2) from postnatal day 1 to 14. Hippocampal brain inflammatory injury was assessed in brain sections by immunohistology for allograft inflammatory factor 1 (AIF1), a marker of microglial activation. Cell proliferation was evaluated by Ki-67 staining, and cell death was determined by TUNEL assay. RNA sequencing of the hippocampus was performed to identify the transcriptional effects of hyperoxia and GSDMD-KO, and qRT-PCR was performed to confirm some of the significantly regulated genes. Results: Hyperoxia-exposed WT mice had increased microglia consistent with activation, which was associated with decreased cell proliferation and increased cell death in the hippocampal area. Conversely, hyperoxia-exposed GSDMD-KO mice exhibited considerable resistance to hyperoxia as O2 exposure failed to increase either AIF1+ or TUNEL+ cell numbers, nor decrease cell proliferation. Hyperoxia exposure differentially regulated 258 genes in WT and only 16 in GSDMD-KO mice compared to room air- exposed WT and GSDMD-KO, respectively. Gene set enrichment analysis showed that in the WT brain, hyperoxia differentially regulated genes associated with neuronal and vascular development and differentiation, axonogenesis, glial cell differentiation, and core development pathways hypoxia-induced factor 1, and neuronal growth factor pathways. These changes were prevented by GSDMD-KO. Conclusion: GSDMD-KO alleviates hyperoxia-induced inflammatory injury, cell survival and death, and alterations of transcriptional gene expression of pathways involved in neuronal growth, development, and differentiation in the hippocampus of neonatal mice. This suggests that GSDMD plays a pathogenic role in preterm brain injury, and targeting GSDMD may be beneficial in preventing and treating brain injury and poor neurodevelopmental outcomes in preterm infants.

Two-stage learning-based prediction of bronchopulmonary dysplasia in very low birth weight infants: a nationwide cohort study

Introduction

The aim of this study is to develop an enhanced machine learning-based prediction models for bronchopulmonary dysplasia (BPD) and its severity through a two-stage approach integrated with the duration of respiratory support (RSd) using prenatal and early postnatal variables from a nationwide very low birth weight (VLBW) infant cohort.

Methods

We included 16,384 VLBW infants admitted to the neonatal intensive care unit (NICU) of the Korean Neonatal Network (KNN), a nationwide VLBW infant registry (2013-2020). Overall, 45 prenatal and early perinatal clinical variables were selected. A multilayer perceptron (MLP)-based network analysis, which was recently introduced to predict diseases in preterm infants, was used for modeling and a stepwise approach. Additionally, we applied a complementary MLP network and established new BPD prediction models (PMbpd). The performances of the models were compared using the area under the receiver operating characteristic curve (AUROC) values. The Shapley method was used to determine the contribution of each variable.

Results

We included 11,177 VLBW infants (3,724 without BPD (BPD 0), 3,383 with mild BPD (BPD 1), 1,375 with moderate BPD (BPD 2), and 2,695 with severe BPD (BPD 3) cases). Compared to conventional machine learning (ML) models, our PMbpd and two-stage PMbpd with RSd (TS-PMbpd) model outperformed both binary (0 vs. 1,2,3; 0,1 vs. 2,3; 0,1,2 vs. 3) and each severity (0 vs. 1 vs. 2 vs. 3) prediction (AUROC = 0.895 and 0.897, 0.824 and 0.825, 0.828 and 0.823, 0.783, and 0.786, respectively). GA, birth weight, and patent ductus arteriosus (PDA) treatment were significant variables for the occurrence of BPD. Birth weight, low blood pressure, and intraventricular hemorrhage were significant for BPD ≥2, birth weight, low blood pressure, and PDA ligation for BPD ≥3. GA, birth weight, and pulmonary hypertension were the principal variables that predicted BPD severity in VLBW infants.

Conclusions

We developed a new two-stage ML model reflecting crucial BPD indicators (RSd) and found significant clinical variables for the early prediction of BPD and its severity with high predictive accuracy. Our model can be used as an adjunctive predictive model in the practical NICU field.

Respiratory and non-respiratory outcomes of bronchopulmonary dysplasia in adolescents: A systematic review

BACKGROUND

There is lack of evidence synthesis on the global consequences of bronchopulmonary dysplasia (BPD) in adolescence.

AIM

Assess the impact of bronchopulmonary dysplasia on respiratory and non-respiratory outcomes in adolescents.

METHODS

A systematic review of studies assessing the outcomes of adolescents aged 10 to 19 years-old with BPD was conducted. We independently screened studies published until 6th March 2023 in PubMed® and Scopus® databases. Data on methodologic design, sample descriptive and findings were extracted from each study. Risk of bias was assessed using quality assessment tools.

RESULTS

Thirty-one studies were included. Adolescents with a history of BPD present with more respiratory symptoms (wheezing, respiratory exacerbations, need for respiratory medication) and twenty-five studies showed a reduction in pulmonary function, with varying impact according to BPD severity and no differences before and after the surfactant era. Spirometry evaluation throughout the years is not consensual, but methacholine and salbutamol response in BPD groups is increased compared to non-BPD groups. Markers of eosinophilic airway inflammation are not increased as in asthma patients. Exercise potential is identical, but data regarding physical capacity and activity are inconsistent. More frequent radiologic abnormalities translate into higher high-resolution computed tomography scores, with linear (72.2 %) and triangular subpleural opacities (58.3 %) as the most common findings. There is a higher risk for special needs in education, but quality of life seems to be equal to non-BPD adolescents.

CONCLUSIONS

BPD negatively impacts both pulmonary and non-pulmonary outcomes in adolescents.

Impaired pulmonary function mediates inattention in young adults born extremely preterm

AIM

To test whether poor childhood pulmonary function explains the relationship between extremely preterm (EP) birth and attention-deficit/hyperactivity disorder (ADHD) symptoms in young adulthood.

METHODS

EPICure birth cohort participants include children born <26 weeks' gestation in the United Kingdom and Ireland in 1995 and their term-born classmates. Predictor was EP birth. Outcomes were inattention/hyperactivity subscale z-scores at 19 years. Forced expiratory volume (FEV1) z-scores in childhood and young adulthood were mediators. We used recursive path analysis to determine the direct effect of EP birth on inattention/hyperactivity and its indirect effect through pulmonary function.

RESULTS

Ninety EP and 47 term-born participants had pulmonary function testing at 11 and 19 years. Inattention z-scores were higher in the EP group (mean difference 0.55 [95% CI 0.11, 0.99]) but not hyperactivity. Compared to term-born peers, EP participants had lower FEV1 z-scores at 11 (mean difference-1.35 [95% CI -1.72, -0.98]) and 19 (mean difference-1.29 [95% CI -1.65, -0.92]). Path models revealed that childhood pulmonary function explained the relationship between EP birth and inattention.

CONCLUSIONS

Extremely preterm young adults have increased risk for inattention compared to term-born peers. Poor pulmonary function appears to underlie this risk. The mechanisms responsible remain unclear and warrant further study.

Placing Ureaplasma within the Context of Bronchopulmonary Dysplasia Endotypes and Phenotypes

Different pathophysiological pathways (endotypes), leading to very preterm birth may result in distinct clinical phenotypes of bronchopulmonary dysplasia (BPD). Ureaplasma is a unique player in the pathogenesis of BPD. The interaction between factors inherent to Ureaplasma (virulence, bacterial load, duration of exposure), and to the host (immune response, infection clearance, degree of prematurity, respiratory support, concomitant infections) may contribute to BPD development in a variable manner. The data reviewed herein support the hypothesis that Ureaplasma, as a representative of the infectious/inflammatory endotype, may produce pulmonary damage predominantly in parenchyma, interstitium, and small airways. In contrast, Ureaplasma may have a very limited role in the pathogenesis of the vascular phenotype of BPD. In addition, if Ureaplasma is a key factor in BPD pathogenesis, its eradication by macrolides should prevent BPD. However, various meta-analyses do not show consistent evidence that this is the case. The limitations of current definitions and classifications of BPD, based on respiratory support needs instead of pathophysiology and phenotypes, may explain this and other failures in strategies aimed to prevent BPD. The precise mechanisms through which Ureaplasma infection leads to altered lung development and how these pathways can result in different BPD phenotypes warrant further investigation.

Child and family factors associated with positive outcomes among youth born extremely preterm

BACKGROUND

To analyze the relationship of child behavioral and communication disorders, and adverse family events, to later-in-life child health and cognitive function among youth born extremely preterm.

METHODS

The study participants were 694 children enrolled in the Extremely Low Gestational Age Newborn Study. At ages 2 and 10, we assessed internalizing and externalizing behaviors, and at age 10, we assessed adverse life events within the family. Associations were evaluated between these child and family factors and positive child health at age 10 years, and global health and cognitive function at age 15 years.

RESULTS

Lower T-scores for internalizing or externalizing behaviors at age 2 were associated with more positive health at age 10. The absence of internalizing behaviors at age 10 was associated with better global child health and better cognitive function at age 15. The absence of communication deficits at age 10 was associated with better cognitive function at age 15. The absence of parent job loss was associated with better global child health at age 15.

CONCLUSION

Among individuals born extremely preterm, child health and cognitive outcomes might be improved by timely interventions to address child behavioral symptoms and the impact of adverse life events in the family.

IMPACT

The absence of child behavioral and communication disorders, and adverse family events, were associated with more positive health, higher global health, and better cognitive function among youth born extremely preterm. Interventions to address behavioral disorders in early childhood, and to reduce the impact of adverse life events on the family, might promote improved health and developmental outcomes for adolescents born extremely preterm.

Health-related quality of life of children born very preterm: a multinational European cohort study

PURPOSE

This study aims to (1) describe the health-related quality of life (HRQoL) outcomes experienced by children born very preterm (28-31 weeks' gestation) and extremely preterm (< 28 weeks' gestation) at five years of age and (2) explore the mediation effects of bronchopulmonary dysplasia (BPD) and severe non-respiratory neonatal morbidity on those outcomes.

METHODS

This investigation was based on data for 3687 children born at < 32 weeks' gestation that contributed to the EPICE and SHIPS studies conducted in 19 regions across 11 European countries. Descriptive statistics and multi-level ordinary linear squares (OLS) regression were used to explore the association between perinatal and sociodemographic characteristics and PedsQL^™ GCS scores. A mediation analysis that applied generalised structural equation modelling explored the association between potential mediators and PedsQL^™ GCS scores.

RESULTS

The multi-level OLS regression (fully adjusted model) revealed that birth at < 26 weeks' gestation, BPD status and experience of severe non-respiratory morbidity were associated with mean decrements in the total PedsQL^™ GCS score of 0.35, 3.71 and 5.87, respectively. The mediation analysis revealed that the indirect effects of BPD and severe non-respiratory morbidity on the total PedsQL^™ GCS score translated into decrements of 1.73 and 17.56, respectively, at < 26 weeks' gestation; 0.99 and 10.95, respectively, at 26-27 weeks' gestation; and 0.34 and 4.80, respectively, at 28-29 weeks' gestation (referent: birth at 30-31 weeks' gestation).

CONCLUSION

The findings suggest that HRQoL is particularly impaired by extremely preterm birth and the concomitant complications of preterm birth such as BPD and severe non-respiratory morbidity.

Motor Optimality Scores are significantly lower in a population of high-risk infants than in infants born moderate-late preterm

BACKGROUND

The Motor Optimality Score-Revised (MOS-R) is a detailed scoring of the General Movement Assessment (GMA), measuring the spontaneous behaviors of infants. Infants born moderate-late preterm are not traditionally followed in high-risk clinics, but have increased risk of neurodevelopmental disability.

AIMS

Compare MOS-R at 3 months corrected age (CA) in high-risk (HR; very preterm or abnormal neuroimaging) infants to infants born moderate-late preterm (MLP).

STUDY DESIGN

In this prospective cohort study, parents of enrolled infants created video recordings using an app at 3 months CA. Videos were scored with the General Movement Assessment (GMA) and MOS-R. MOS-R scores were divided into "higher-risk" (≤19) and "lower-risk" (≥20).

SUBJECTS

181 infants born MLP or categorized as HR.

RESULTS

Among enrolled infants, 68 (38 %) were in the MLP group, and 113 infants were in the HR group. The HR group had 3.8 increased odds of having an aberrant GMA score compared to the MLP group (p < 0.01, 95 % CI 1.38-10.52). The HR group had significantly lower MOS-R scores (mean 20) than the MLP group (mean 24; p < 0.001; 95%CI 3.3-7.3). The HR group had 11.2 increased odds of having a higher-risk MOS-R score (95%CI 2.5-47.6, p < 0.001) than MLP group. Infants were most likely to have a lower MOS-R score if they had any of the following: VP shunt placement, periventricular leukomalacia, or bronchopulmonary dysplasia.

CONCLUSIONS

Aberrant GMA and higher-risk MOS-R scores were more common in infants at high-risk, reflecting history of brain lesions and younger gestational age at birth.

Frequent hypoxemia found in infants with bronchopulmonary dysplasia after weaning home oxygen

OBJECTIVE

Parental reports and brief clinical examinations are the primary information used to assist clinicians in weaning home supplemental oxygen in infants with bronchopulmonary dysplasia (BPD). Recorded nocturnal oximetry provides an objective assessment of hypoxemia; however, it is unknown if it identifies clinically undetected hypoxemia in the home setting. Our objective was to determine if nocturnal oximetry can identify unreported hypoxemia in infants with BPD who appear ready to wean from supplemental oxygen.

STUDY DESIGN

We conducted a retrospective chart review of infants born <32 weeks gestation with BPD who were discharged to home receiving supplemental oxygen and completed recorded nocturnal oximetry in room air during an 18-month period. Abnormal oximetry was defined as >5 min with SpO₂  < 90% and/or an oxyhemoglobin desaturation index (ODI4) >5. Comparative analysis of patients with normal and abnormal overnight oximetry was performed using Fisher Exact and Wilcoxon signed-rank test.

RESULTS

Thirty-five former premature infants completed nocturnal oximetry at 5.8 (3.4-8.3) months corrected age. Nocturnal oximetry was abnormal as defined in 67% of the cohort (n = 21). Five percent of patients were hypoxemic, 52% had frequent desaturation events, and 43% had both. No significant differences existed in neonatal characteristics between patients with normal and abnormal studies.

CONCLUSIONS

Nocturnal oximetry was abnormal in the majority of infants with BPD who were otherwise clinically ready to wean from oxygen support, suggesting that recorded home oximetry could be a feasible and useful tool to evaluate for otherwise clinically unapparent nocturnal hypoxemia in patients with BPD.

Respiratory morbidity and neurodevelopmental outcomes in infants born preterm: A complex web

This commentary is on the original article by Yu et al. on pages 1246–1253 of this issue.

Aberrant methylation of Serpine1 mediates lung injury in neonatal mice prenatally exposed to intrauterine inflammation

Background

Intrauterine inflammation (IUI) alters epigenetic modifications in offspring, leading to lung injury. However, the epigenetic mechanism underlying IUI-induced lung injury remains uncertain. In the present study, we aim to investigate the effect of IUI on lung development, and to identify the key molecule involved in this process and its epigenetic regulatory mechanism.

Results

Serpine1 was upregulated in the lung tissue of neonatal mice with IUI. Intranasal delivery of Serpine1 siRNA markedly reversed IUI-induced lung injury. Serpine1 overexpression substantially promoted cell senescence of both human and murine lung epithelial cells, reflected by decreased cell proliferation and increased senescence-associated β-galactosidase activity, G0/G1 cell fraction, senescence marker, and oxidative and DNA damage marker expression. IUI decreased the methylation level of the Serpine1 promoter, and methylation of the promoter led to transcriptional repression of Serpine1. Furthermore, IUI promoted the expression of Tet1 potentially through TNF-α, while Tet1 facilitated the demethylation of Serpine1 promoter. DNA pull-down and ChIP assays revealed that the Serpine1 promoter was regulated by Rela and Hdac2. DNA demethylation increased the recruitment of Rela to the Serpine1 promoter and induced the release of Hdac2.

Conclusion

Increased Serpine1 expression mediated by DNA demethylation causes lung injury in neonatal mice with IUI. Therefore, therapeutic interventions targeting Serpine1 may effectively prevent IUI-induced lung injury.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13578-022-00901-8.

Early-life respiratory trajectories and neurodevelopmental outcomes in infants born very and extremely preterm: A retrospective study

AIM

To determine whether early-life respiratory trajectories are associated with neurodevelopmental impairment (NDI) in infants born very and extremely preterm.

METHOD

The daily type of respiratory supports in the first 8 weeks after birth were analysed in 546 infants (285 males, 261 females; median gestational age = 28.0 weeks, interquartile range = 3 weeks), comprising 301 infants born very preterm (gestation = 28-30 weeks) and 245 infants born extremely preterm (gestation <28 weeks), who survived to discharge from 2004 to 2018 and received follow-up assessment by Bayley Scales of Infant and Toddler Development at a corrected age of 24 months. NDI included cognition or motor impairment, moderate and severe cerebral palsy, or visual and hearing impairment.

RESULTS

Clustering analysis identified three respiratory patterns with increasing severity: improving; slowly improving; and delayed improvement. These were significantly associated with increasing rates of NDI in infants born very and extremely preterm and smaller head circumference in infants born extremely preterm (both p < 0.001). By day 28, the proportion of infants who were under different categories of ventilation support significantly differed according to the three trajectory groups in infants born very and extremely preterm (both p < 0.05). Models that included adverse respiratory trajectories demonstrated more negative impacts on neurodevelopment than those without.

INTERPRETATION

An adverse early-life respiratory trajectory was associated with NDI at follow-up, especially in infants born extremely preterm, suggesting a lung-brain axis of preterm birth.

WHAT THIS PAPER ADDS

Clustering analysis identified three respiratory trajectories with increasing severity in infants born preterm. Increasing severity of respiratory trajectories was associated with increasing rates of neurodevelopmental impairment. Adverse respiratory trajectories had a significantly negative impact on neurodevelopmental outcomes.

Psychologist's Unique Role in Improving Quality of Life of Children with Chronic Lung Diseases and Their Families

Pediatric chronic lung diseases burden their patients and families with heavy treatment loads, frequent extensive clinic visits to multiple providers, frequent emergency department visits and hospitalizations, and contribute to significant psychosocial issues with caregiver's burnout. The purpose of this chapter is to outline the psychosocial impact of the major pediatric chronic lung diseases and the unique role of the psychologist in relieving this burden. These include severe asthma, cystic fibrosis, bronchopulmonary dysplasia, and dependence on home mechanical ventilation.

Neurodevelopmental outcome of Italian preterm ELBW infants: an eleven years single center cohort

BACKGROUND

Preterm extremely low birth weight infants (ELBWi) are known to be at greater risk of developing neuropsychiatric diseases. Identifying early predictors of outcome is essential to refer patients for early intervention. Few studies have investigated neurodevelopmental outcomes in Italian ELBWi. This study aims to describe neurodevelopmental outcome at 24 months of corrected age in an eleven-year single-center cohort of Italian ELBWi and to identify early risk factors for adverse neurodevelopmental outcomes.

METHODS

All infants born with birth weight < 1000 g and admitted to the Neonatal Intensive Care Unit of the "Fondazione IRCCS Policlinico San Matteo" hospital in Pavia, Italy, from Jan 1, 2005 to Dec 31, 2015 were eligible for inclusion. At 24 months, Griffiths' Mental Developmental Scales Extended Revised (GMDS-ER) were administered. Neurodevelopmental outcome was classified as: normal, minor sequelae (minor neurological signs, General Quotient between 76 and 87), major sequelae (cerebral palsy; General Quotient ≤ 75; severe sensory impairment). Univariate and multivariate multinomial logistic regression models were performed to analyze the correlation between neonatal variables and neurodevelopmental outcome.

RESULTS

176 ELBWi were enrolled (mean gestational age 26.52 weeks sd2.23; mean birthweight 777.45 g sd142.89). 67% showed a normal outcome at 24 months, 17% minor sequelae and 16% major sequelae (4.6% cerebral palsy on overall sample). The most frequent major sequela was cognitive impairment (8.52%). In the entire sample the median score on the Hearing-Speech subscale was lower than the median scores recorded on the other subscales and showed a significantly weaker correlation to each of the other subscales of the GMDS-ER. Severely abnormal cUS findings (RRR 10.22 p 0.043) and bronchopulmonary dysplasia (RRR 4.36 p 0.008) were independent risk factors for major sequelae and bronchopulmonary dysplasia for minor sequelae (RRR 3.00 p 0.018) on multivariate multinomial logistic regression.

CONCLUSIONS

This study showed an improvement in ELBWI survival rate without neurodevelopmental impairment at 24 months compared to previously reported international cohorts. Cognitive impairment was the most frequent major sequela. Median scores on GMDS-ER showed a peculiar developmental profile characterized by a selective deficit in the language domain. Severely abnormal cUS findings and bronchopulmonary dysplasia were confirmed as independent risk factors for major sequelae.

Cord blood antimicrobial peptide LL37 levels in preterm neonates and association with preterm complications

BACKGROUND

Cathelicidin/LL-37 plays a significant role in the human immune defense reaction. Preterm human immature organs being exposed to inflammation-induced injury was the critical denominator leading to the common preterm associated complications. Previous study showed LL37 concentration in preterm neonates was lower in tracheal aspirates and breast milk as compared to term infants. An adults study showed decreased LL-37 levels was a risk factor for patients in developing severe chronic obstructive pulmonary disease (COPD). However, little is known about the regulation of human cord blood LL37 in preterm neonates and the association with preterm complications. This study was designed to investigate the concentration of LL37 in cord blood of preterm infants and correlation with preterm complications.

METHODS

Singleton infants born in June 2017 to August 2021 in the study hospital were enrolled. Maternal and neonatal clinical characteristics were collected. LL37 levels, pro-inflammatory factor interleukin-6 (IL-6) and tumor necrosis factor-a (TNF-a) in cord blood and LL37 levels in serum 48-72 hours after birth were measured by enzyme-linked immunosorbent assay. The serum level of LL37 in preterm and term neonates were compared, the perinatal factors possibly affecting the LL37 levels were investigated and the relationship between LL37 level and preterm outcomes were analyzed.

RESULTS

Cord blood LL37 levels in preterm infants were lower than that in term neonates. Cord blood LL37 level was positively correlated with gestational age in preterm. Prenatal steroid administration in preterm neonates decreased cord blood LL37 level. LL37 level was obviously lower in patients with bronchopulmonary dysplasia (BPD). Multiple line regression analysis showed higher LL37 level in cord blood was an independent protective factor for BPD. The concentration of pro-inflammatory factor IL-6 was negatively correlated with LL37.

CONCLUSION

Cord blood LL37 levels increased during gestation and decreased after perinatal steroid usage. Very preterm infants who displayed higher cord blood LL37 level had reduced risk of developing BPD. Regulation of pro-inflammatory cytokine IL-6 may be associated with the protective effect of LL37 on BPD.

Endotypes of Prematurity and Phenotypes of Bronchopulmonary Dysplasia: Toward Personalized Neonatology

Bronchopulmonary dysplasia (BPD), the chronic lung disease of prematurity, is increasingly recognized as the consequence of a pathological reparative response of the developing lung to both antenatal and postnatal injury. According to this view, the pathogenesis of BPD is multifactorial and heterogeneous with different patterns of antenatal stress (endotypes) that combine with varying postnatal insults and might distinctively damage the development of airways, lung parenchyma, interstitium, lymphatic system, and pulmonary vasculature. This results in different clinical phenotypes of BPD. There is no clear consensus on which are the endotypes of prematurity but the combination of clinical information with placental and bacteriological data enables the identification of two main pathways leading to birth before 32 weeks of gestation: (1) infection/inflammation and (2) dysfunctional placentation. Regarding BPD phenotypes, the following have been proposed: parenchymal, peripheral airway, central airway, interstitial, congestive, vascular, and mixed phenotype. In line with the approach of personalized medicine, endotyping prematurity and phenotyping BPD will facilitate the design of more targeted therapeutic and prognostic approaches.

Temporal trends in respiratory care and bronchopulmonary dysplasia in very preterm infants over a 10-year period in Spain

OBJECTIVE

To evaluate trends in respiratory care practices and bronchopulmonary dysplasia (BPD) among very preterm infants born in Spain between 2010 and 2019.

STUDY DESIGN

This was a retrospective cohort study of data obtained from a national population-based database (SEN1500 network). Changes in respiratory care and BPD-free survival of infants with gestational age (GA) of 23⁰-31⁶ weeks and <1500 g were assessed over two 5-year periods. Temporal trends were examined by joinpoint and Poisson regression models and expressed as the annual per cent change and adjusted relative risk (RR) for the change per year.

RESULTS

A total of 17 952 infants were included. In the second period, infants were less frequently intubated in the delivery room and during neonatal intensive care unit stay. This corresponded with an increase in use of non-invasive ventilation techniques. There were no significant differences between the periods in BPD-free survival or survival without moderate-to-severe BPD. After adjusting for covariates, the RR for the change per year was significant for the following variables: never intubated (RR 1.03, 95% CI 1.02 to 1.04); intubation in the delivery room (RR 0.98, 95% CI 0.97 to 0.99); use of nasal intermittent positive pressure ventilation (RR 1.08, 95% CI 1.05 to 1.11); and BPD-free survival (only in the group with the lowest GA; RR 0.98, 95% CI 0.97 to 0.99).

CONCLUSION

Our findings reveal significant changes in respiratory care practices between 2009 and 2019. Despite an increase in use of non-invasive respiratory strategies, BPD-free survival did not improve and even worsened in the group with the lowest GA (23⁰-25⁶).

Perinatal Hyperoxia and Developmental Consequences on the Lung-Brain Axis

Approximately 11.1% of all newborns worldwide are born preterm. Improved neonatal intensive care significantly increased survival rates over the last decades but failed to reduce the risk for the development of chronic lung disease (i.e., bronchopulmonary dysplasia (BPD)) and impaired neurodevelopment (i.e., encephalopathy of prematurity (EoP)), two major long-term sequelae of prematurity. Premature infants are exposed to relative hyperoxia, when compared to physiological in-utero conditions and, if needed to additional therapeutic oxygen supplementation. Both are associated with an increased risk for impaired organ development. Since the detrimental effects of hyperoxia on the immature retina are known for many years, lung and brain have come into focus in the last decade. Hyperoxia-induced excessive production of reactive oxygen species leading to oxidative stress and inflammation contribute to pulmonary growth restriction and abnormal neurodevelopment, including myelination deficits. Despite a large body of studies, which unraveled important pathophysiological mechanisms for both organs at risk, the majority focused exclusively either on lung or on brain injury. However, considering that preterm infants suffering from BPD are at higher risk for poor neurodevelopmental outcome, an interaction between both organs seems plausible. This review summarizes recent findings regarding mechanisms of hyperoxia-induced neonatal lung and brain injury. We will discuss common pathophysiological pathways, which potentially link both injured organ systems. Furthermore, promises and needs of currently suggested therapies, including pharmacological and regenerative cell-based treatments for BPD and EoP, will be emphasized. Limited therapeutic approaches highlight the urgent need for a better understanding of the mechanisms underlying detrimental effects of hyperoxia on the lung-brain axis in order to pave the way for the development of novel multimodal therapies, ideally targeting both severe preterm birth-associated complications.

Extreme prematurity: Risk and resiliency

Individuals born extremely preterm (before 28 weeks of gestation) comprise only about 0.7% of births in the United States and an even lower proportion in other high resource countries. However, these individuals account for a disproportionate number of children with cerebral palsy, intellectual deficit, autism spectrum disorder, attention deficit hyperactivity disorder, and epilepsy. This review describes two large multiple center cohorts comprised of individuals born extremely preterm: the EPICURE cohort, recruited 1995 in the United Kingdom and the Republic of Ireland, and the Extremely Low Gestational Age Newborn (ELGAN), recruited 2002-2004 in five states in the United States. The primary focus of these studies has been neurodevelopmental disorders, but also of interest are growth, respiratory illness, and parent- and self-reported global health and well-being. Both of these studies indicate that among individuals born extremely preterm the risks of most neurodevelopmental disorders are increased. Early life factors that contribute to this risk include perinatal brain damage, some of which can be identified using neonatal head ultrasound, bronchopulmonary dysplasia, and neonatal systemic inflammation. Prenatal factors, particularly the family's socioeconomic position, also appear to contribute to risk. For most adverse outcomes, the risk is higher in males. Young adults born extremely preterm who have neurodevelopmental impairment, as compared to those without such impairment, rate their quality of life lower. However, young adults born extremely preterm who do not have neurodevelopmental impairments rate their quality of life as being similar to that of young adults born at term. Finally, we summarize the current state of interventions designed to improve the life course of extremely premature infants, with particular focus on efforts to prevent premature birth and on postnatal efforts to prevent adverse neurodevelopmental outcomes.

Pulmonary Magnetic Resonance Imaging of Ex-preterm Children with/without Bronchopulmonary Dysplasia

RATIONALE

Children born prematurely, particularly those with bronchopulmonary dysplasia, have persisting lung abnormalities requiring longitudinal monitoring. Pulmonary ultra-short echo time magnetic resonance imaging (MRI) measurements may provide sensitive markers of persisting lung abnormalities, and have not been evaluated in school-aged children born prematurely.

OBJECTIVE

To compare pulmonary MRI and pulmonary function test measurements in preterm-born school-aged children with and without bronchopulmonary dysplasia.

METHODS

Children aged 7-9 years, born extremely preterm, with and without bronchopulmonary dysplasia, were recruited from three centers. Participants underwent pulmonary ultra-short echo time MRI and pulmonary function tests. Primary outcomes included total proton density and proton density at full expiration, measured using MRI. Multiple linear regression analysis was performed, adjusting for gestational age and bronchopulmonary dysplasia. Associations between MRI and pulmonary function were tested.

RESULTS

Thirty-five children were included in the primary analysis (24 with bronchopulmonary dysplasia, 11 without); 29 completed pulmonary function tests, of whom 11 (38%) had airflow limitation. Children with bronchopulmonary dysplasia had 44% (CI: 10%, 66%) lower mean total proton density (mean ± SD: 3.6 ± 2.6) compared to those without (6.1 ± 4.0). Those with bronchopulmonary dysplasia had 25% (CI: 3%, 42%) lower proton density at full expiration than those without. Lower total proton density and proton density at full expiration were moderately correlated with greater residual volume, residual volume/total lung capacity, and lung clearance index (Spearman correlations for total proton density: -0.42, -0.57, and -0.53, respectively. Spearman correlations for proton density at full expiration: -0.28, -0.57, and -0.45, respectively).

CONCLUSIONS

School-aged preterm-born children with bronchopulmonary dysplasia have parenchymal tissue abnormalities measured using ultrashort MRI proton density, compared to those without. MRI proton density correlated with pulmonary function measures indicative of gas trapping. Clinical trial registered with ClinicalTrials.gov (NCT02921308).

Cognitive flexibility in 12-month-old preterm and term infants is associated with neurobehavioural development in 18-month-olds

There is growing evidence that preterm children are at an increased risk of poor executive functioning, which underlies behavioural and attention problems. Previous studies have suggested that early cognitive flexibility is a possible predictor of later executive function; however, how it develops in infancy and relates to the later neurobehavioural outcomes is still unclear in the preterm population. Here, we conducted a longitudinal study to investigate oculomotor response shifting in 27 preterm and 25 term infants at 12 months and its relationship with general cognitive development and effortful control, which is a temperamental aspect closely associated with executive function, at 18 months. We found that moderate to late preterm and term infants significantly inhibited previously rewarded look responses, while very preterm infants did not show significant inhibition of perseverative looking at 12 months. Moreover, lower inhibition of perseverative looking was significantly associated with lower general cognitive development and attentional shifting at 18 months. These findings suggest that the early atypical patterns of oculomotor response shifting may be a behavioural marker for predicting a higher risk of negative neurobehavioural outcomes, including attention-related problems in preterm children.

Protective Effects of 18β-Glycyrrhetinic Acid on Neonatal Rats with Hyperoxia Exposure

Bronchopulmonary dysplasia (BPD) is a common devastating pulmonary complication in preterm infants. Supplemental oxygen is a lifesaving therapeutic measure used for premature infants with pulmonary insufficiency. However, oxygen toxicity is a significant trigger for BPD. Oxidative stress disrupts lung development, accompanied by increased pro-inflammatory cytokines and chemokines expression and immune cells infiltration in lung tissue. Licorice, a typical traditional herbal medicine, is commonly used in the medicine and food industries. 18β-Glycyrrhetinic acid (18β-GA), a primary active ingredient of licorice, has powerful anti-oxidative and anti-inflammatory effects. This study aimed to determine whether 18β-GA has a protective effect on neonatal rats with hyperoxia exposure. Newborn Sprague-Dawley rats were kept in either 21% (normoxia) or 80% O₂ (hyperoxia) continuously from postnatal day (PN) 1 to 14. 18β-GA was injected intragastrically at 50 or 100 mg/kg body weight once a day from PN 1 to 14. We examined the body weight and alveolar development and measured ROS level and the markers of pulmonary inflammation. Mature-IL-1β and NF-κB pathway proteins, and the NLRP3 inflammasome, were assessed; concurrently, caspase-1 activity was measured. Our results indicated that hyperoxia resulted in alveolar simplification and decreased bodyweight of neonatal rats. Hyperoxia increased ROS level and pulmonary inflammation and activated NF-κB and the NLRP3 inflammasome. 18β-GA treatment inhibited the activation of NF-κB and the NLRP3 inflammasome, decreased ROS level and pulmonary inflammation, improved alveolar development, and increased the bodyweight of neonatal rats with hyperoxia exposure. Our study demonstrates that 18β-GA has a protective effect on neonatal rats with hyperoxia exposure.

Prediction Models for Bronchopulmonary Dysplasia in Preterm Infants: A Systematic Review

OBJECTIVE

To provide an overview and critical appraisal of prediction models for bronchopulmonary dysplasia (BPD) in preterm infants.

METHODS

We searched PubMed, Embase, and the Cochrane Library to identify relevant studies (up to November 2021). We included studies that reported prediction model development and/or validation of BPD in preterm infants born at ≤32 weeks and/or ≤1,500 g birth weight. We extracted the data independently based on the CHecklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling Studies (CHARMS). We assessed risk of bias and applicability independently using the Prediction model Risk Of Bias ASsessment Tool (PROBAST).

RESULTS

Twenty-one prediction models from 13 studies reporting on model development and 21 models from 10 studies reporting on external validation were included. Oxygen dependency at 36 weeks' postmenstrual age was the most frequently reported outcome in both development studies (71%) and validation studies (81%). The most frequently used predictors in the models were birth weight (67%), gestational age (62%), and sex (52%). Nearly all included studies had high risk of bias, most often due to inadequate analysis. Small sample sizes and insufficient event patients were common in both study types. Missing data were often not reported or were discarded. Most studies reported on the models' discrimination, while calibration was seldom assessed (development, 19%; validation, 10%). Internal validation was lacking in 69% of development studies.

CONCLUSION

The included studies had many methodological shortcomings. Future work should focus on following the recommended approaches for developing and validating BPD prediction models.

The value of plasma insulin-like growth factor 1 and interleukin-18 in the diagnosis of bronchopulmonary dysplasia in premature infants

OBJECTIVE

To explore the diagnostic value of IGF-1 and IL-18 in premature infants with BPD.

METHODS

Through a prospective observational study, the serum samples of infants in the BPD group and the non-BPD group were collected at different targeted time points, and the serum IGF-1 and IL-18 concentrations were dynamically monitored by ELISA. The Student t-test and one-way analysis of variance were adopted to analyze data, and the receiver operating characteristic (ROC) curve was used to test the diagnostic value.

RESULT

A total of 90 VLBW premature infants admitted to NICU between January 2020 and 2021 were finally included. Compared with the non-BPD group, infants diagnosed with BPD had a significantly lower serum concentration of IGF-1 (P < 0.05) but a higher level of IL-18 (P < 0.05) on days 1, 7, 14, and 28 after birth. With the ROC curve analysis, the serum concentration IGF-1 on day 14 and IL-18 on day 28 reported high sensitivity and specificity to predict the risk of BPD (IGF-1: sensitivity: 89.29%, specificity: 77.78%, AUC: 0.8710; IL-18: sensitivity: 53.57%, specificity: 83.33%, AUC: 0.7887). And more substantial predictive power was found in combined analysis of IGF-1 and serum IL-18 on day 14: the sensitivity was 91.07% and the specificity was 83.33%, with the AUC of 0.9142.

CONCLUSION

IGF-1 and IL-18 might be closely involved in the occurrence and development of BPD. The serum concentration of IGF-1 combined with IL-18 could be potentially sensitive markers for the early diagnosis and severity of BPD.

Favorable parental perception of behaviour at two years' corrected age in very preterm-born children

Problems in behavioural and emotional outcome are amongst the long-term sequelae of preterm birth. The exact prevalence and associations with perinatal risk factors are unknown. Minimal research has been performed in pre-school aged children, compared to school age. The primary aim of this study was to determine the prevalence of parent-reported behavioural and emotional problems at the age of two in children born at less than 30 weeks' gestational age and/or birth weight less than 1000 g. The secondary aim was to determine whether perinatal factors were associated with the behavioural and emotional outcome. Perinatal characteristics of 144 preterm-born children from the NeoLiFeS cohort were collected retrospectively. Of these children, 101 parents filled out a Childs Behaviour Checklist (CBCL) at the corrected age of two. The results of the CBCL tests were presented as Z-scores, a Z-score of 0 indicating the mean of behavioural scores in the norm population. A Z-score higher than zero indicates less behavioural problems than average, a negative Z-score indicates more problems. Associations between perinatal risk factors and CBCL-scores were analysed using linear regression analyses. Prevalences of clinically relevant CBCL scores were low, 4%, 2% and 5% for total score, internalizing score or externalizing score, respectively. Being part of a twin was associated with higher internalizing Z-scores, indicating less problems in emotional behaviour. Bronchopulmonary dysplasia was associated with lower Z-scores in total and externalizing behaviour. In conclusion, in our cohort generally very few problems in behavioural and emotional outcome were reported at the age of two.

Neurodevelopmental outcomes of infants with bronchopulmonary dysplasia

Preterm infants with bronchopulmonary dysplasia (BPD), and particularly those who develop the most severe forms of chronic lung disease during the neonatal period, are at high risk for poor developmental outcomes throughout childhood. Infants who require mechanical ventilation at 36 weeks post-menstrual age have significantly increased odds for cerebral palsy, developmental delay at 2 years, and poor academic achievement and low intelligence quotient in adolescence. Over the past several decades, many therapies and care strategies, including steroids, continuous positive airway pressure, surfactant, and other medications have been introduced into clinical practice. These approaches have changed the epidemiology of BPD in very preterm infants. However, BPD remains common and strongly associated with poor development throughout childhood. Only caffeine has been proven to reduce BPD and improve childhood developmental outcomes. In future research, it will be essential to better understand the developmental sequelae of BPD beyond school age and to test interventions to improve developmental trajectories in this population. As new management strategies for BPD are developed, it will be essential to rigorously evaluate both short-term and long-term effects before they are introduced into routine neonatal practice.

Association of High Screen-Time Use With School-age Cognitive, Executive Function, and Behavior Outcomes in Extremely Preterm Children

Importance

Both preterm birth and increased screen time are known to be associated with an increase in risk of developmental and behavioral sequelae. The association between high screen time or a television or computer in the bedroom in early school age and adverse cognitive, executive function, language, and behavior outcomes of extremely preterm children (EPT) is not well understood.

Objective

To assess the association of high screen time with cognition, language, executive function, and behavior of EPT children aged 6 to 7 years; a second objective was to examine the association between high screen time and rates of structured physical activity and weight.

Design, Setting, and Participants

This cohort study was a secondary analysis from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Surfactant Positive Airway Pressure and Pulse Oximetry Randomized Trial Neuroimaging and Neurodevelopmental Outcomes school-aged cohort and includes 414 EPT children born between February 1, 2005, and February 28, 2009, and evaluated in between 2012 and 2016 at ages 6 years 4 months to 7 years 2 months. The study was conducted from July 7, 2012, and August 15, 2016, and data were analyzed between December 10, 2018, and April 1, 2021.

Exposures

Cohorts included children exposed to low (≤2 hours per day) vs high (>2 hours per day) amounts of screen time and by the presence (no vs yes) of a television/computer in the bedroom.

Main Outcomes and Measures

In addition to growth parameters, assessments included the Wechsler Intelligence Scale for Children-IV, the Behavior Rating Inventory of Executive Function, the Developmental Neuropsychological Assessment, the Conners 3rd Edition-Parent Short-Form, and the Social Communication Questionnaire.

Results

Of the 414 children included in the analysis, 227 (55%) were boys; mean (SD) birth weight was 870.6 (191) g. A total of 238 children (57%) had high screen time and 266 (64%) had a television/computer in their bedroom. In multivariable linear regressions adjusted for center, male sex, gestational age, and social determinants of health, high screen time was independently associated with the following mean (SE) test score changes: lower full-scale IQ (-3.92 [1.64]; P = .02); an increase in association with deficits in executive functions, including metacognition (8.18 [3.01]; P = .007), global executive function (7.49 [2.99]; P = .01), inhibition (-0.79 [0.38]; P = .03), and Conners 3rd Edition-Parent Short-Form inattention (3.32 [1.67]; P = .047). A television/computer in the bedroom was associated with an increase in inhibition (-0.80 [0.39]; P = .04) and hyperactivity/impulsivity (3.50 [1.75]; P = .046) problems.

Conclusions and Relevance

The findings of this study suggest that high screen time contributes to adverse cognitive, executive function, and behavior outcomes at ages 6 to 7 years in children born at less than 28 weeks. These findings support the need for clinicians to have heightened awareness of the risks for EPT children and discuss both the benefits and risks of screen time with families.

Neurodevelopmental outcomes in preterm infants with retinopathy of prematurity

Over the past decade there has been a paradigm shift in the treatment of retinopathy of prematurity (ROP) with the introduction of antivascular endothelial growth factor (anti-VEGF) treatments. Anti-VEGF agents have the advantages of being easier to administer, requiring less anesthesia, having the potential for improved peripheral vision, and producing less refractive error than laser treatment. On the other hand, it is known that intravitreal administration of anti-VEGF agents lowers VEGF levels in the blood and raises the theoretical concern of intraocular anti-VEGF causing deleterious effects in other organ systems, including the brain. As a result, there has been increased attention recently on neurodevelopmental outcomes in infants treated with anti-VEGF agents. These studies should be put into context with what is known about systemic comorbidities, socioeconomic influences, and the effects of extreme prematurity itself on neurodevelopmental outcomes. We summarize what is known about neurodevelopmental outcomes in extremely preterm infants with ROP, discuss the implications for determining the neurodevelopmental status using neurodevelopmental testing as well as other indicators, and review the existing literature relating to neurodevelopmental outcomes in babies treated for ROP.

The relationship between intermittent hypoxemia events and neural outcomes in neonates

This brief review examines 1) patterns of intermittent hypoxemia in extremely preterm infants during early postnatal life, 2) the relationship between neonatal intermittent hypoxemia exposure and outcomes in both human and animal models, 3) potential mechanistic pathways, and 4) future alterations in clinical care that may reduce morbidity. Intermittent hypoxemia events are pervasive in extremely preterm infants (<28 weeks gestation at birth) during early postnatal life. An increased frequency of intermittent hypoxemia events has been associated with a range of poor neural outcomes including language and cognitive delays, motor impairment, retinopathy of prematurity, impaired control of breathing, and intraventricular hemorrhage. Neonatal rodent models have shown that exposure to short repetitive cycles of hypoxia induce a pathophysiological cascade. However, not all patterns of intermittent hypoxia are deleterious and some may even improve neurodevelopmental outcomes. Therapeutic interventions include supplemental oxygen, pressure support and pharmacologic drugs but prolonged hyperoxia and pressure exposure have been associated with cardiopulmonary morbidity. Therefore, it becomes imperative to distinguish high risk from neutral and/or even beneficial patterns of intermittent hypoxemia during early postnatal life. Identification of such patterns could improve clinical care with targeted interventions for high-risk patterns and minimal or no exposure to treatment modalities for low-risk patterns.

Hyperoxia-activated circulating extracellular vesicles induce lung and brain injury in neonatal rats

Hyperoxia-induced lung injury plays a key role in the development of bronchopulmonary dysplasia (BPD), characterized by inflammatory injury and impaired lung development in preterm infants. Although BPD is a predictor of poor neurodevelopmental outcomes, currently it is uncertain how lung injury contributes to brain injury in preterm infants. Extracellular vesicles (EVs) are a heterogeneous group of cell-derived membranous structures that regulate intercellular and inter-organ communications. Gasdermin D (GSDMD) has emerged as a key executor of inflammasome-mediated cell death and inflammation. In this study, we utilized a neonatal rat model of BPD to assess if hyperoxia stimulates lung release of circulating EVs and if these EVs induce lung and brain injury. We found that hyperoxia-exposed rats had elevated numbers of plasma-derived EVs compared to rats maintained in room air. These EVs also had increased cargos of surfactant protein C, a marker of type II alveolar epithelial cells (AEC), and the active (p30) form of GSDMD. When these EVs were adoptively transferred into normal newborn rats via intravenous injection, they were taken up both by lung and brain tissues. Moreover, EVs from hyperoxic animals induced not only the pathological hallmarks of BPD, but also brain inflammatory injury in recipient rats, as well as inducing cell death in cultured pulmonary vascular endothelial cells and neural stem cells (NSC). Similarly, hyperoxia-exposed cultured AEC-like cells released EVs that also contained increased GSDMD-p30 and these EVs induced pyroptotic cell death in NSC. Overall, these data indicate that hyperoxia-activated circulating EVs mediate a lung to brain crosstalk resulting in brain injury and suggest a mechanism that links lung injury and neurodevelopmental impairment in BPD infants.

[Clinical significance of amplitude-integrated electroencephalography in preterm infants with bronchopulmonary dysplasia]

OBJECTIVE

To study the changes and clinical significance of amplitude-integrated electroencephalography (aEEG) in preterm infants with bronchopulmonary dysplasia (BPD).

METHODS

A total of 156 preterm infants with a gestational age of ≤ 32⁺⁶ weeks who were diagnosed with BPD were enrolled as the BPD group, and 156 preterm infants without BPD who were hospitalized during the same period of time were enrolled as the control group. The aEEG scoring system for preterm infants was used to compare aEEG results between the two groups during hospitalization. A stratified analysis was conducted based on the examination time (at the corrected gestational age of ≤ 28⁺⁶ weeks, 29-30⁺⁶ weeks, 31-32⁺⁶ weeks, 33-34⁺⁶ weeks, 35-36⁺⁶ weeks, and 37-38⁺⁶ weeks).

RESULTS

Compared with the non-BPD group, the BPD group had a significantly lower total aEEG score at the corrected gestational age of 33-34⁺⁶ weeks (P < 0.001). The mild BPD group had a significantly lower total aEEG score than the non-BPD group at the corrected gestational age of 33-34⁺⁶ weeks (P < 0.05); the moderate BPD group had a significantly lower total aEEG score than the non-BPD group at the corrected gestational ages of 31-32⁺⁶ weeks, 33-34⁺⁶ weeks, and 35-36⁺⁶ weeks (P < 0.05); the severe BPD group had a significantly lower total aEEG score than the non-BPD group at all corrected gestational ages except ≤ 28⁺⁶ weeks and 29-30⁺⁶ weeks (P < 0.05).

CONCLUSIONS

Preterm infants with BPD (especially moderate to severe BPD) have a lower aEEG score than those without BPD, suggesting that their nervous system development may lag behind that of non-BPD preterm infants with the same gestational age. Therefore, early nervous system evaluation and intervention are necessary for preterm infants with BPD.

[Clinical significance of amplitude-integrated electroencephalography in preterm infants with bronchopulmonary dysplasia]

OBJECTIVE

To study the changes and clinical significance of amplitude-integrated electroencephalography (aEEG) in preterm infants with bronchopulmonary dysplasia (BPD).

METHODS

A total of 156 preterm infants with a gestational age of ≤ 32+6 weeks who were diagnosed with BPD were enrolled as the BPD group, and 156 preterm infants without BPD who were hospitalized during the same period of time were enrolled as the control group. The aEEG scoring system for preterm infants was used to compare aEEG results between the two groups during hospitalization. A stratified analysis was conducted based on the examination time (at the corrected gestational age of ≤ 28+6 weeks, 29-30+6 weeks, 31-32+6 weeks, 33-34+6 weeks, 35-36+6 weeks, and 37-38+6 weeks).

RESULTS

Compared with the non-BPD group, the BPD group had a significantly lower total aEEG score at the corrected gestational age of 33-34+6 weeks (P < 0.001). The mild BPD group had a significantly lower total aEEG score than the non-BPD group at the corrected gestational age of 33-34+6 weeks (P < 0.05); the moderate BPD group had a significantly lower total aEEG score than the non-BPD group at the corrected gestational ages of 31-32+6 weeks, 33-34+6 weeks, and 35-36+6 weeks (P < 0.05); the severe BPD group had a significantly lower total aEEG score than the non-BPD group at all corrected gestational ages except ≤ 28+6 weeks and 29-30+6 weeks (P < 0.05).

CONCLUSIONS

Preterm infants with BPD (especially moderate to severe BPD) have a lower aEEG score than those without BPD, suggesting that their nervous system development may lag behind that of non-BPD preterm infants with the same gestational age. Therefore, early nervous system evaluation and intervention are necessary for preterm infants with BPD.

Neonatal Adverse Outcomes, Neonatal Birth Risks, and Socioeconomic Status: Combined Influence on Preterm Infants' Cognitive, Language, and Motor Development in Brazil

BACKGROUND

This study extended previous research by investigating the combined effects of neonatal birth risks, neonatal adverse outcomes, and socioeconomic status on preterm neurodevelopment.

METHOD

A total of 184 preterm infants were assessed using the Bayley Scales of Infant Development III in a follow-up clinic in southern Brazil. Structural equation modeling was conducted with 3 latent variables (neonatal birth risks, neonatal adverse outcomes, and socioeconomic status) and 3 outcomes (cognitive, language, and motor development).

RESULTS

The analyses showed that neonatal adverse outcomes were associated with infants' cognitive (b = -0.45, P < .001), language (b = -0.23, P = .001), and motor (b = -0.51, P < .001) development. Socioeconomic status also explained the variances (cognitive: b = 0.20, P = .006; language: b = 0.28, P = .001; and motor: b = 0.21, P = .004), whereas neonatal birth risks remained significant only in the motor development (b = 0.15, P = .040).

CONCLUSION

This study suggests that the most evident contributors to poor neurodevelopment were adverse outcomes and socioeconomic risk factors.

Impact of inhaled corticosteroids on the neurodevelopmental outcomes in chronically ventilated extremely low birth weight preterm infants

BACKGROUND

Few studies have assessed the long-term impact of inhaled corticosteroids (ICS) in preterm infants. This study evaluated the neurodevelopmental outcomes of chronically ventilated extremely low birth weight (ELBW) preterm infants exposed to ICS.

METHODS

The medical records of ELBW preterm infants admitted to two tertiary-level neonatal intensive care units from 2008 to 2014 were reviewed. Infants intubated for more than 28 days were included. The neurodevelopmental outcomes were compared at 24 months corrected age, between those with ICS exposure (inhaled group, IH) and those without it (non-inhaled group, NIH), by using the Bayley-Scale-of-Infant-and-Toddler Development-III (BSID-III).

RESULTS

Out of the 115 infants included, 64 had an ICS exposure. The incidence of the morbidities at the time of discharge, was comparable between the two groups, except for the duration of oxygen and mechanical ventilation dependence (IH 124.8 ± 40.3 days vs. NIH: 101.0 ± 28.6 days, p < 0.001 and IH 60.0 ± 25.8 days vs. NIH: 42.3 ± 14.2 days, p < 0.001, respectively). Multiple logistic regression analysis at 24 months corrected age revealed no significant differences in the BSID-III scores and in the incidence of cerebral palsy and neurodevelopmental impairment.

CONCLUSION

The late ICS exposure was not associated with neurodevelopmental impairment at 24 months corrected age in chronically ventilated ELBW infants; however, it did not reduce the duration of their dependence on oxygen and mechanical ventilation.

Language, Motor, and Cognitive Outcomes of Toddlers Who Were Born Preterm

Purpose The purpose of this study was to examine the language, motor, and cognitive abilities of children born preterm in four categories: (a) healthy preterm infants, (b) infants of diabetic mothers, (c) infants with respiratory distress syndrome, and (d) infants with chronic lung disease when the children were 30 months, uncorrected age. Comorbidity of language, motor, and cognitive skills was examined, along with predictor variables. Method A total of 148 children who were born preterm participated and were assessed using bivariate tests and logistic regression on standardized assessment scores. Results Controlling for the children's gestational age (GA), overall language ability was significantly lower in the infants of diabetic mothers group compared to the healthy preterm infant group, and expressive language skills were significantly lower for the chronic lung disease group than the respiratory distress syndrome group. The children with language delays on at least one measure were significantly more likely to have cognitive, motor, or both delays. Lower maternal education was a significant predictor for language and cognitive delays, and younger GA was a significant predictor for language, motor, and cognitive delays. Conclusion Assessment of the preterm infant from a biosystems approach allows the speech-language pathologist to take into consideration maternal education, diagnosis at preterm birth, and GA, which were found to impact the language, motor, and cognitive outcomes of children born preterm. Our findings further reinforce the concept of the whole child in that children born preterm who display language delays should be screened for co-occurring motor and/or cognitive delays.

Postnatal steroid therapy is associated with autism spectrum disorder in children and adolescents of very low birth weight infants

BACKGROUND

This study evaluates the association between major neonatal morbidities and autism spectrum disorder (ASD) in children and adolescents born of very low birth weight (VLBW).

METHODS

Historical cohort study using the Israel national VLBW infant database linked with the Maccabi Healthcare Services (MHS) medical records. The study cohort comprised 4963 VLBW subjects born from 1999 to 2012, >1 year of age. Multivariable logistic regression analyses were used to assess factors associated with ASD.

RESULTS

The diagnosis of ASD was confirmed in 113 children (2.3%). Infants with major neonatal morbidities had higher rates of ASD; however, in the multivariable analyses these were not significantly associated with ASD: severe intraventricular hemorrhage (OR 1.21 [95% CI 0.60-2.45]), post-hemorrhagic hydrocephalus (OR 1.77 [0.73-4.29]), periventricular leukomalacia (OR 1.02 [0.42-2.51]), severe retinopathy of prematurity (OR 1.91 [0.995-3.67]), and bronchopulmonary dysplasia (OR 1.44 [0.84-2.45]). Postnatal steroid therapy when included separately was associated with an OR of 1.97 [1.18-3.29] for ASD. This association remained significant when postnatal steroid therapy was included with each of the neonatal morbidities (ORs ranging from 1.91 to 2.11).

CONCLUSIONS

This study suggests a significant association between postnatal steroid therapy and ASD in VLBW infants. This possible association should be considered in future studies evaluating potential risk factors for ASD in preterm infants.