Gestational Age Alters Assessment of Neonatal Abstinence Syndrome

Neonatal abstinence syndrome (NAS) due to maternal opioid use affects both term and preterm infants; however, the relationship between gestational age and clinical symptomatology is still poorly understood. In this study, we compared the clinical features and outcomes of NAS in infants admitted to a neonatal intensive care unit (NICU) based on gestational age groups: preterm (32-36 6/7 weeks) and term (37 weeks or older). A retrospective data analysis was conducted using the medical records of infants with a diagnosis of NAS admitted to a regional perinatal center between 2014 and 2020. A modified Finnegan scoring system was used based on three different symptom categories, including Central Nervous System (CNS), Gastrointestinal (GI) and Other. In total, 166 infants with a diagnosis of NAS were included, with 52 (31%) who were preterm and 114 (69%) who were term. The highest NAS score was significantly lower for the preterm group than for the term group. Preterm infants were less likely to require first-line pharmacotherapy with morphine (52% versus 75%) and to experience GI symptoms during their hospitalization. Newer NAS assessment modalities, such as eat, sleep, console (ESC), may overcome the existing challenges of traditional scoring systems, but will require validation in preterm infants.