METHODS: A cross-sectional analysis of all inpatient hospital births for newborns with a NAS (ICD9 CM code: 779.5) and drug use code (ICD9 CM codes: 760.72, 760.75), extracted for 2008 to 2013 time-period from the Arizona (AZ) and New Mexico (NM) Hospital Inpatient Discharge Data (HIDD)
RESULTS: During 2008-2013 there were a total of 1,472 NAS cases in AZ and 888 in NM. The overall NAS rate during 2008-2013 was 2.83 (95% CI, 2.68- 2.97) per 1000 births in AZ and 5.64 (95% CI, 5.28 -5.99) per 1000 births in New Mexico. NAS newborns were more likely to be low birth weight, have respiratory complications, more likely to have feeding difficulties, and more likely to be on state Medicaid insurance. NAS rates for the AZ border region (4.06 per 1000 births [95% CI, 3.68-4.44]) was significantly higher than the state rate (2.83 [95% CI, 2.68- 2.97]). In NM, the border region rate (2.22 per 1000 births [95% CI, 1.60-2.85]) was significantly lower than the state rate (5.64 [95% CI, 5.28-5.99]).
CONCLUSIONS: The dramatic increase in the incidence of NAS in both AZ and NM Southwest border states poses critical challenges to population health infrastructure for provision of services for newborn infants with regards to ongoing care as well as infrastructure for prevention, surveillance, and developing evidence-based strategies through applied research.