WIP 53 - Dose-related cardiopulmonary outcomes associated with systemic postnatal steroids at near term corrected age in extremely preterm infants.

Publication Number: WIP 53.7427

Katherine McKee, University of Oklahoma College of Medicine, Oklahoma City, OK, United States; Marjorie Makoni, Oklahoma University Health Sciences Center, Oklahoma Coty, OK, United States; Jamie L.. Miller, University of Oklahoma College of Pharmacy, Oklahoma City, OK, United States; Mohanageetha Ardhanari, Oklahoma Childrens Hospital at OU Health, Oklahoma City, OK, United States; Holden C. Bulbow, University of Oklahoma College of Medicine, Oklahoma City, OK, United States; Samba Ceesay, The university of Oklahoma HSC, Norman, OK, United States; Michael Anderson, The University of Oklahoma Health Science Center, Oklahoma City, OK, United States; Trassanee Chatmethakul, University of Oklahoma Health Science Center, Oklahoma City, OK, United States

Background: Postnatal steroid exposure has been linked to alteration of cardiac architecture in extremely premature infants. The underlying mechanisms remain unclear and proposed mechanisms include induction of apoptosis in cardiac myocytes, reduced collagen synthesis, and changes in cardiac growth regulation and indirect reduction of cardiac workload. Previous studies have explored the impact of postnatal steroids on cardiac architecture with short term effects of increased blood pressure and ventricular hypertrophy. However, there is a gap in research regarding the total cumulative exposure to postnatal steroids and its effects on the rapidly evolving cardiac geometry during near term postmenstrual age (PMA).

Objective: This study aims to describe the relationship between altered ventricular geometry, measured by echocardiography, and cumulative postnatal steroid exposure in extremely premature infants.

Design/Methods: This descriptive retrospective cohort study includes preterm infants born < 32 weeks gestational age admitted to a level IV NICU from January 1, 2021 to May 31, 2023. Exclusion criteria include discharge before 36 weeks PMA, lack of echocardiographic data at 2 target time points (within first 14 days of life and 36 weeks PMA/prior to discharge), known genetic disorders or congenital heart defects (except for PDA, ASD/PFO, and small VSD less than 1 mm), and receipt of Extracorporeal Membrane Oxygenation (ECMO) therapy. Demographic and echocardiographic data (assessment of LV and RV performance/geometry, pulmonary hemodynamics, and characteristics of shunts) will be collected.
Descriptive statistics will be used with categorical variables reported as frequencies and continuous variables as means or medians. Linear regression will assess potential dose-response relationships between steroid exposure and heart size, while analysis of covariance will control for confounding variables such as gestational age, birth weight, and sex. Multivariable regression will evaluate the independent effects of cumulative steroid dose and other relevant factors on heart size.