Systemic corticosteroid regimens for prevention of bronchopulmonary dysplasia in preterm infants

Corticosteroids for the prevention and treatment of bronchopulmonary dysplasia: an overview of systematic reviews

BACKGROUND

Bronchopulmonary dysplasia (BPD) remains an important complication of prematurity. Pulmonary inflammation plays a central role in the pathogenesis of BPD, explaining the rationale for investigating postnatal corticosteroids. Multiple systematic reviews (SRs) have summarised the evidence from numerous randomised controlled trials (RCTs) investigating different aspects of administrating postnatal corticosteroids. Besides beneficial effects on the outcome of death or BPD, potential short- and long-term harms have been reported.

OBJECTIVES

The primary objective of this overview was to summarise and appraise the evidence from SRs regarding the efficacy and safety of postnatal corticosteroids in preterm infants at risk of developing BPD.

METHODS

We searched the Cochrane Database of Systematic Reviews, MEDLINE, Embase, CINAHL, and Epistemonikos for SRs in April 2023. We included all SRs assessing any form of postnatal corticosteroid administration in preterm populations with the objective of ameliorating pulmonary disease. All regimens and comparisons were included. Two review authors independently checked the eligibility of the SRs comparing corticosteroids with placebo, and corticosteroids with different routes of administration and regimens. The included outcomes, considered key drivers in the decision to administer postnatal corticosteroids, were the composite outcome of death or BPD at 36 weeks' postmenstrual age (PMA), its individual components, long-term neurodevelopmental sequelae, sepsis, and gastrointestinal tract perforation. We independently assessed the methodological quality of the included SRs by using AMSTAR 2 (A Measurement Tool to Assess Systematic Reviews) and ROBIS (Risk Of Bias In Systematic reviews) tools. We assessed the certainty of the evidence using GRADE. We provided a narrative description of the characteristics, methodological quality, and results of the included SRs.

MAIN RESULTS

We included nine SRs (seven Cochrane, two non-Cochrane) containing 87 RCTs, 1 follow-up study, and 9419 preterm infants, investigating the effects of postnatal corticosteroids to prevent or treat BPD. The quality of the included SRs according to AMSTAR 2 varied from high to critically low. Risk of bias according to ROBIS was low. The certainty of the evidence according to GRADE ranged from very low to moderate. Early initiated systemic dexamethasone (< seven days after birth) likely has a beneficial effect on death or BPD at 36 weeks' PMA (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.81 to 0.95; number needed to treat for an additional beneficial outcome (NNTB) 16, 95% CI 10 to 41; I2 = 39%; 17 studies; 2791 infants; moderate-certainty evidence) and on BPD at 36 weeks' PMA (RR 0.72, 95% CI 0.63 to 0.82; NNTB 13, 95% CI 9 to 21; I2 = 39%; 17 studies; 2791 infants; moderate-certainty evidence). Early initiated systemic hydrocortisone may also have a beneficial effect on death or BPD at 36 weeks' PMA (RR 0.90, 95% CI 0.82 to 0.99; NNTB 18, 95% CI 9 to 594; I2 = 43%; 9 studies; 1376 infants; low-certainty evidence). However, these benefits are likely accompanied by harmful effects like cerebral palsy or neurosensory disability (dexamethasone) or gastrointestinal perforation (both dexamethasone and hydrocortisone). Late initiated systemic dexamethasone (≥ seven days after birth) may have a beneficial effect on death or BPD at 36 weeks' PMA (RR 0.75, 95% CI 0.67 to 0.84; NNTB 5, 95% CI 4 to 9; I2 = 61%; 12 studies; 553 infants; low-certainty evidence), mostly contributed to by a beneficial effect on BPD at 36 weeks' PMA (RR 0.76, 95% CI 0.66 to 0.87; NNTB 6, 95% CI 4 to 13; I2 = 14%; 12 studies; 553 infants; low-certainty evidence). No harmful side effects were shown in the outcomes chosen as key drivers to the decision to start or withhold late systemic dexamethasone. No effects, either beneficial or harmful, were found in the subgroup meta-analyses of late hydrocortisone studies. Early initiated inhaled corticosteroids probably have a beneficial effect on death and BPD at 36 weeks' PMA (RR 0.86, 95% CI 0.75 to 0.99; NNTB 19, 95% CI not applicable; I2 = 0%; 6 studies; 1285 infants; moderate-certainty evidence), with no apparent adverse effects shown in the SRs. In contrast, late initiated inhaled corticosteroids do not appear to have any benefits or harms. Endotracheal instillation of corticosteroids (budesonide) with surfactant as a carrier likely has a beneficial effect on death or BPD at 36 weeks' PMA (RR 0.60, 95% CI 0.49 to 0.74; NNTB 4, 95% CI 3 to 6; I2 = 0%; 2 studies; 381 infants; moderate-certainty evidence) and on BPD at 36 weeks' PMA. No evidence of harmful effects was found. There was little evidence for effects of different starting doses or timing of systemic corticosteroids on death or BPD at 36 weeks' PMA, but potential adverse effects were observed for some comparisons. Lowering the dose might result in a more unfavourable balance of benefits and harms. Moderately early initiated systemic corticosteroids, compared with early systemic corticosteroids, may result in a higher incidence of BPD at 36 weeks' PMA. Pulse dosing instead of continuous dosing may have a negative effect on death and BPD at 36 weeks' PMA. We found no differences for the comparisons of inhaled versus systemic corticosteroids.

AUTHORS' CONCLUSIONS

This overview summarises the evidence of nine SRs investigating the effect of postnatal corticosteroids in preterm infants at risk for BPD. Late initiated (≥ seven days after birth) systemic administration of dexamethasone is considered an effective intervention to reduce the risk of BPD in infants with a high risk profile for BPD, based on a favourable balance between benefits and harms. Endotracheal instillation of corticosteroids (budesonide) with surfactant as a carrier is a promising intervention, based on the beneficial effect on desirable outcomes without (so far) negative side effects. Pending results of ongoing large, multicentre RCTs investigating both short- and long-term effects, endotracheal instillation of corticosteroids (budesonide) with surfactant as a carrier is not appropriate for clinical practice at present. Early initiated (< seven days after birth) systemic dexamethasone and hydrocortisone and late initiated (≥ seven days after birth) hydrocortisone are considered ineffective interventions, because of an unfavourable balance between benefits and harms. No conclusions are possible regarding early and late inhaled corticosteroids, as more research is needed.

Effects of postnatal corticosteroids on lung development in newborn animals. A systematic review

BACKGROUND

Postnatal systemic corticosteroids reduce the risk of bronchopulmonary dysplasia but the effect depends on timing, dosing, and type of corticosteroids. Animal studies may provide valuable information on these variable effects. This systematic review summarizes the effects of postnatal systemic corticosteroids on lung development in newborn animals.

METHODS

A systematic search was performed in PubMed and Embase in December 2022. The protocol was published on PROSPERO (CRD42021177701).

RESULTS

Of the 202 eligible studies, 51 were included. Only newborn rodent studies met the inclusion criteria. Most studies used dexamethasone (98%). There was huge heterogeneity in study outcome measures and corticosteroid treatment regimens. Reporting of study quality indicators was mediocre and risk of bias was unclear due to poor reporting of study methodology. Meta-analysis showed that postnatal corticosteroids caused a decrease in body weight as well as persistent alveolar simplification. Subgroup analyses revealed that healthy animals were most affected.

CONCLUSION

In newborn rodents, postnatal systemic corticosteroids have a persistent negative effect on body weight and lung development. There was huge heterogeneity in experimental models, mediocre study quality, unclear risk of bias, and very small subgroups for meta-analysis which limited firm conclusions.

IMPACT

Postnatal corticosteroids reduce the risk of bronchopulmonary dysplasia but the effect depends on timing, dosing, and type of corticosteroids while the underlying mechanism of this variable effect is unknown. This is the first systematic review and meta-analysis of preclinical newborn animal studies reviewing the effect of postnatal systemic corticosteroids on lung development. In newborn rodent models, postnatal corticosteroids have a persistent negative effect on body weight and lung alveolarization, especially in healthy animals.

Outcomes of postnatal systemic corticosteroids administration in ventilated preterm newborns: a systematic review of randomized controlled trials

Introduction

Prolonged mechanical ventilation, commonly used to assist preterm newborns, increases the risk of developing bronchopulmonary dysplasia (BPD). In recent decades, studies have demonstrated that systemic corticosteroids play a significant role in the prevention and management of BPD. In this systematic review of randomized controlled trials (RCTs), we evaluated the association between the administration of systemic corticosteroids in preterm infants and its long-term outcomes, such as neurodevelopment, growth, extubation rate, and related adverse effects.

Methods

We conducted an electronic search in Medline, Scopus, and PubMed using the following terms: "premature infants" and "corticosteroids." We considered all RCTs published up to June 2023 as eligible. We included all studies involving preterm newborns treated with systemic corticosteroids and excluded studies on inhaled corticosteroids.

Results

A total of 39 RCTs were evaluated. The influence of steroids administered systemically during the neonatal period on long-term neurological outcomes remains unknown, with no influence observed for long-term growth. The postnatal administration of systemic corticosteroids has been found to reduce the timing of extubation and improve respiratory outcomes. Dexamethasone appears to be more effective than hydrocortisone, despite causing a higher rate of systemic hypertension and hyperglycemia. However, in the majority of RCTs analyzed, there were no differences in the adverse effects related to postnatal corticosteroid administration.

Conclusion

Dexamethasone administered during the neonatal period appears to be more effective than hydrocortisone in terms of respiratory outcomes; however, caution should be taken when administering dexamethasone. Data derived from current evidence, including meta-analyses, are inconclusive on the long-term effects of the administration of systemic steroids in preterm infants or the possibility of neurodevelopmental consequences.

Factors associated with the response to postnatal dexamethasone use in very low birthweight infants: a nationwide cohort study

BACKGROUND

Dexamethasone is widely used as a systemic corticosteroid to treat and prevent bronchopulmonary dysplasia (BPD) in preterm infants. We evaluated the current epidemiology of dexamethasone use to prevent BPD and analyse the factors associated with the response to dexamethasone in very low birthweight infants using a nationwide database.

METHODS

We included very low birthweight infants born between January 2013 and December 2020 with a gestational age of 23-31 weeks using data from the Korean Neonatal Network registry. Patients were grouped based on their dexamethasone use into 'Dex' or 'No Dex' groups. Clinical variables and data were collected, and the annual trends of dexamethasone use and the proportion of patients who received dexamethasone according to gestational age were analysed. Respiratory outcomes were compared between the groups. Univariate and multivariate analyses were performed to analyse factors associated with the response to dexamethasone in BPD.

RESULTS

Of 11 261 eligible infants, 2313 (20.5%) received dexamethasone, and 1714 (74.1%) of them were diagnosed with moderate-to-severe BPD. The 8-year annual prevalence of dexamethasone use was 17.7-22.3%. The 'Dex' group had more moderate-to-severe BPD, more frequent invasive ventilation use at a postmenstrual age of 36 weeks and longer ventilator duration. Birth weight, 5-minute APGAR score, pulmonary hypertension within the first 28 days, surgical treatment of patent ductus arteriosus, medical treatment of patent ductus arteriosus, pathological chorioamnionitis, hydrocortisone or budesonide use, surgical management of necrotising enterocolitis and fungal sepsis were associated with BPD after dexamethasone use.

CONCLUSIONS

Approximately 20.5% of preterm infants received dexamethasone, and the frequency increased as gestational age decreased. Poor response to dexamethasone was associated with antenatal and postnatal inflammation, low birth weight and early pulmonary hypertension.

Respiratory management and outcomes in high-risk preterm infants with development of a population outcome dashboard

INTRODUCTION

Bronchopulmonary dysplasia (BPD) is associated with adverse long-term respiratory and neurodevelopmental outcomes. No recent studies examined the changing respiratory management and outcomes, particularly severe BPD, across a whole population.

PURPOSE

Evaluate the temporal trends in the respiratory management and outcomes of preterm infants born below 32 weeks gestational age and develop an individualised dashboard of the incidence of neonatal outcome.

METHODS

Using the National Neonatal Research Database, we determined changes in respiratory management, BPD rates, postdischarge respiratory support and mortality in 83 463 preterm infants in England and Wales from 2010 to 2020.

RESULTS

Between 2010 and 2020, antenatal corticosteroids use increased (88%-93%, p<0.0001) and neonatal surfactant use decreased (65%-60%, p<0.0001). Postnatal corticosteroid use increased, especially dexamethasone (4%-6%, p<0.0001). More recently, hydrocortisone and budesonide use increased from 2% in 2017 to 4% and 3%, respectively, in 2020 (p<0.0001). Over the study period, mortality decreased (10.1%-8.5%), with increases in BPD (28%-33%), severe BPD (12%-17%), composite BPD/death (35%-39%) and composite severe BPD/death (21%-24%) (all p<0.0001). Overall, 11 684 infants required postdischarge respiratory support, increasing from 13% to 17% (p<0.0001), with 1843 infants requiring respiratory pressure support at discharge. A population dashboard (https://premoutcome.github.io/) depicting the incidence of mortality and respiratory outcomes, based on gestation, sex and birthweight centile, was developed.

CONCLUSION

More preterm infants are surviving with worse respiratory outcomes, particularly severe BPD requiring postdischarge respiratory support. Ultimately, these survivors will develop chronic respiratory diseases requiring greater healthcare resources.