Perinatal Factors Associated with Successful Pharmacologic Closure of the Patent Ductus Arteriosus in Premature Infants.

The patent ductus arteriosus (PDA) is associated with significant morbidity and mortality in preterm infants. While pharmacologic closure of the PDA is common and effective, it can be difficult to identify which patients will respond. As such, the objective of this study was to identify factors associated with successful pharmacologic closure of the PDA. We hypothesized that clinical factors such as gestational age, birth weight, and hypertensive disorders of pregnancy would be associated with successful closure. We performed a retrospective cohort study of preterm infants who received pharmacologic treatment for a PDA at two large neonatal intensive care units in Boston, MA between January 2016 and December 2021. Infants were excluded if they received prophylactic indomethacin, had early termination of therapy, did not have an echocardiogram prior to therapy, or had congenital heart disease. The primary outcome was closure after initial course. Relevant perinatal data were collected on enrolled infants. Of the 215 enrolled infants, 131 (61%) had successful closure. Older gestational age (OR, 1.23; 95% CI,1.03-1.47), male sex (OR, 2.17; 95% CI,1.18-3.99), and maternal preeclampsia (OR, 2.75; 95% CI,1.07-7.02) were associated with successful closure. Infants who received postnatal steroids (OR, 0.49; 95% CI,0.25-0.96) were less likely to have had successful closure. In this study, we identified previously established associations of gestational age and male sex with successful pharmacologic closure. However, the associations with maternal preeclampsia and postnatal steroids are novel. While further investigation is warranted, these associations can help inform decision-making around management of the PDA.