335: Does race affect late preterm neonatal respiratory morbidity?

Abstract

Differences in respiratory disease by race are well described in early preterm infants, but largely unknown for late preterm infants. Our objective was to determine whether neonatal respiratory morbidity differs by race in neonates born late preterm. Secondary analysis of a randomized trial of women at high risk for late preterm delivery. Our study was limited to women with non-anomalous, singleton gestations delivering between 34+0 to 36+6 weeks. Women were categorized into 4 groups by race: Black, White, Asian, or other/mixed. Primary outcome was a neonatal composite of treatment in the first 72 hours (CPAP or high flow nasal cannula >2 hours, oxygen >4 hours, ECMO or mechanical ventilation) or stillbirth or neonatal death before 72 hours. Secondary outcomes include major respiratory morbidity (MRM, the primary outcome, extending CPAP or high-flow nasal cannula to >12 continuous hours and oxygen to at least 24 continuous hours) and other outcomes listed in Table 1. The primary and secondary outcomes were assessed in the active and placebo groups separately, and the full cohort was assessed for treatment interaction with race. We fit a logistic regression model to adjust for confounders related to respiratory morbidity. Of 2,331 included women, 26.9% (n= 627) were Black/African American, 57.1% White (n=1333), 3.56% Asian (n=83) and 12.36% (n=288) were other/mixed. In the placebo group the rate of the primary outcome was significantly higher in Whites (18.6%) and Asians (22.8%) compared to the African American/Black group (12.3%) (p 0.03) (table 1). Adjusting for confounders, Black infants still had lower but non-significant rates of the primary outcome. The primary predictor for respiratory morbidity was a prior pregnancy with neonatal respiratory morbidity. Findings were similar in the steroid group (Table 1), but MRM was less common in black compared with white infants (aOR 0.45, 95%CI 0.24, 0.83) (table 2). However, a prior pregnancy with neonatal respiratory complications was no longer associated with respiratory morbidity after receipt of betamethasone. Assessing the full cohort, there were no significant interactions between steroids and race. Late term respiratory morbidity is lower in black infants and reduced further by steroid administration. While history of pregnancy with previous neonatal respiratory disease is the strongest risk factor for recurrence, this risk factor was mitigated by receipt of steroids.View Large Image Figure ViewerDownload Hi-res image Download (PPT)