BACKGROUND: Nationwide opioid abuse or dependence during pregnancy has doubled since 1998 from 1.7 to 3.9 per 1000 delivery admissions in 2011. Neonatal abstinence syndrome (NAS) is a withdrawal syndrome in newborns following birth and is caused by maternal opiate use during pregnancy. The study examines trends, maternal and infant characteristics, and neonatal outcomes in Delaware using linked Hospital Inpatient Discharge Data (HDD) and Birth Certificate (BC) data for 2010-2013.
METHODS: A retrospective case-cohort analysis of linked HDD and BC data was utilized to examine the incidence and costs of NAS in Delaware (HDD) and describe birth outcomes and characteristics of mothers delivering infants with NAS (BC). All Delaware hospital births for newborns with an NAS (779.5) diagnosis using International Classification of Diseases – Ninth Revision Clinical Modification (ICD9 CM) codes were extracted for 2010 to 2013. Chi-square comparisons that are significant (p<.05) are presented.
RESULTS: During 2010-2013 there were a total of 41,038 hospital births and a total of 639 NAS cases identified in Delaware using HDD. The overall NAS rate during 2010-2013 was 15.57 (95% CI: 14.36 – 16.77) per 1000 births. There was a substantial increase (~56%) in NAS rates, from 11.86 per 1000 births per year in 2010 to 18.47 in 2013 in comparison to the 2012 U.S. rate of 5.8 per 1000 births per year. NAS newborns were significantly more likely to be low birth weight, born premature, or small for gestation. The median charges billed for an NAS newborn were approximately $14,000 with a median length of stay of nine days as compared to a non-NAS newborn with a median cost of approximately $2,500 and a median length of stay of two days. Maternal characteristics from the birth certificate data indicated that over 70 percent of mothers who delivered NAS infants smoked during pregnancy compared to 11 percent who did not deliver a NAS infant. Further, over seven percent (n = 46) of these mothers tested positive for Hepatitis C during this time-period.
CONCLUSIONS: The relatively high rate of NAS in Delaware coupled with high smoking rates among mothers delivering NAS infants poses critical challenges for the care of women and children. Delaware currently utilizes home visiting programs, such as the Nurse Family Partnership (NFP), to identify and enroll high risk women of child-bearing age and connects them to preconception and interconception services through the Healthy Women and Healthy Babies program.