Twenty percent to 40% of infants exposed to in utero opioid were delivered preterm. There is currently no neonatal abstinence syndrome (NAS) scoring tool known to accurately evaluate preterm opioid-exposed infants. This can lead to difficulties in titrating pharmacotherapy in this population.
To describe NAS symptoms in preterm opioid-exposed infants in comparison with matched full-term controls.
This was a retrospective cohort study from a single tertiary care center of methadone-exposed infants born between 2006 and 2010. Using modified Finnegan scale scores recorded every 3 to 4 hours beginning at 6 hours of life until 24 to 48 hours after medication discontinuation, NAS symptoms was compared between 45 preterm infants and 49 full-term matched controls. Concurrent neonatal medical diagnoses were also compared.
The median gestational age in the preterm group was 35 weeks (interquartile range [IQR] = 33-36) versus 39 weeks (IQR = 38-40) in the term group. Preterm infants scored less frequently for many items including sleep disturbance (24.4% vs 46.2%), tremors (77.9% vs 89.7%), muscle tone (87.9% vs 97.4%), sweating (2.1% vs 9.4%), nasal stuffiness (11.9% vs 20.5%), and loose stools (7.0% vs 14.3%) than full-term controls. Preterm infants scored more frequently for hyperactive moro reflex (26.4% vs 5.5%), tachypnea (19.3% vs 16.1%), and poor feeding (24.6% vs 11.8%).
Provider awareness of differences in manifestations of preterm and term infants with NAS, as well as concurrent prematurity diagnoses that can influence NAS scoring, is needed. These findings mandate the development of a modified NAS scoring tool for the preterm NAS population.
A preterm NAS scoring tool needs to be developed and validated to more accurately evaluate and treat preterm opioid-exposed infants.
Department of Obstetrics & Gynecology, University of Massachusetts, Worcester, Massachusetts (Dr Allocco); Department of Pediatrics, Boston Medical Center, Boston, Massachusetts (Ms Melker and Dr Wachman); Boston University School of Medicine, Boston, Massachusetts (Ms Rojas-Miguez); Department of Neonatology, Children's Hospital Boston, Boston, Massachusetts (Ms Bradley); and Department of Epidemiology, Boston University School of Public Health, Boston, Massachusetts (Dr Hahn).
Correspondence: Elisha M. Wachman, MD, Department of Pediatrics, Boston Medical Center, 771 Albany St, Dowling 4103, Boston, MA 02118 (Elisha.Wachman@bmc.org).
This study was conducted at Boston Medical Center.
The authors have no conflicts of interest to report.