481 - Association between Antenatal Corticosteroids and Neonatal Outcomes among Very Preterm Infants Born to Mothers with Hypertensive Disorders of Pregnancy: A Multicenter Cohort Study

Poster Number: 481
Publication Number: 481.2820

Background: The relationship between antenatal corticosteroids (ACS) and preterm infants born to mothers with hypertensive disorders of pregnancy (HDP) has been a subject of controversy.

Objective: This study aimed to ascertain the association between the use of ACS prior to delivery and neonatal outcomes in very preterm infants born to mothers with HDP.

Design/Methods: This multicenter cohort study included all infants with gestational ages ranging from 24+0 to 31+6 weeks, admitted to tertiary NICUs within the Chinese Neonatal Network (CHNN) from 2019 to 2021. Infants with severe congenital malformations, those administered steroids for other medical conditions, cases with missing information on maternal hypertensive disorders of pregnancy, and those born to mothers without HDP were excluded. The use of ACS was categorized as either any treatment or no treatment. The primary outcome was the utilization of surfactant and/or invasive mechanical ventilation within the first 72 hours of life (to define severe RDS, sRDS for short). Univariate and multivariable logistic regression analyses assessed the relationship between ACS and neonatal outcomes. Subgroup analysis was used to assess whether different uses of ACS and the severity of HDP affected the relationship between ACS and neonatal outcomes. Sensitivity analysis was performed using propensity score matching (PSM) with caliper matching to account for potential confounders to validate the robustness of the outcomes.

Results: Of the 4,582 infants included in the study, 3,806 (83.1%) were exposed to ACS. Infants' gestational age exposed to ACS was 30.3, higher than infants who weren't exposed to ACS (P=0.0009). ACS use was associated with a decrease in sRDS (67.8% vs. 76.7%, P < 0.0001). Multivariable logistic regression analyses revealed a 40% reduction in sRDS, a 46% reduction in mortality, and a 38% reduction in BPD among infants born to mothers with HDP exposed to ACS (aOR = 0.60, 95% CI 0.49–0.74; aOR = 0.54, 95% CI 0.42–0.70; and aOR = 0.62, 95% CI 0.52–0.74, respectively). The Single complete course of ACS had the most significant impact (aOR = 0.58, 95% CI 0.47–0.72) during different uses of ACS. PSM analysis, matching 646 pairs of very preterm infants born to mothers with HDP, demonstrating a 33% reduction in sRDS among those exposed to ACS (aOR = 0.67, 95% CI 0.52–0.87).

Conclusion(s): The administration of ACS was significantly associated with reduced respiratory diseases and mortality in very preterm infants born to mothers with HDP. For mothers with HDP at risk of preterm delivery, ACS should be administered to improve neonatal outcomes.