P1.188: Longitudinal Assessment of Developmental Outcomes in Infants with Neonatal Opioid Withdrawal Syndrome at 6 and 12 Months

Background: Infants treated for neonatal opioid withdrawal syndrome (NOWS) require close monitoring, partially due to the potential for long-term effects of prenatal and postnatal opioid exposure on brain development. Current primary therapy of NOWS is morphine sulfate (MS), an opioid. However, clonidine, a non-opioid, is another possible treatment for NOWS. The objective of this study was to investigate if there is a difference in developmental outcomes at 6 and 12 months in infants diagnosed with NOWS who were treated with MS versus clonidine as the primary therapy.

Methods: Follow-up study of a double blinded, randomized clinical trial evaluating neonates diagnosed with NOWS, between 2/2018 and 10/ 2024. Subjects were randomized to NOWS treatment with either MS or clonidine as primary therapy. Majority of the subjects consented for the study did not require pharmacological management (No-Tx group) and were treated with supportive therapies. Subjects' guardians completed the 6 and 12 months Ages and Stages Questionnaires (ASQ-3) over the phone. Differences in ASQ results in those treated with MS versus clonidine and those in the treated versus non-treated groups were compared using chi-square analysis.

Results: Of the 149 consented neonates, 69 (46%) received pharmacological treatment (Tx group) and of the 69 treated patients, 34 (49%) received MS and 35 (51%) clonidine.  There was no significant difference in gestational age (38.1 versus 38.5 weeks), birth weight (2904 versus 3067 grams), gender (males 55% versus 52%), or race in the Tx and No-Tx groups, or between MS and clonidine group.  There was no difference in developmental outcomes between the Tx and No-Tx groups at 6 or 12 months (p = 0.835, p = 0.64, respectively).  There was, also, no difference in development between subjects treated with MS vs clonidine therapy at 6 months or 12 months (p = 0.4). However, twice as many patients who were treated with MS had an abnormal ASQ at 12 months, compared to the clonidine group (66% versus 33%, p = 0.4).

Conclusion: There were no differences in developmental outcomes between children treated versus not treated for NOWS, and those treated with MS versus clonidine.  However, those treated with morphine may have a higher chance of abnormal development at 12 months compared to those treated with clonidine, which needs to be further evaluated with larger studies.