Importance: Neonatal abstinence syndrome (NAS) is a medical condition among neonates experiencing substance withdrawal due to the mother's substance use during pregnancy. While previous studies suggest that the overall incidence and annual costs of NAS are increasing, to date, the long-term costs have yet to be demonstrated in Medicaid populations.
Objective: To examine the demographic differences and long-term costs of care for neonates diagnosed with vs not diagnosed with NAS.
Design, setting, and participants: This cohort study used claims data from the Alabama Medicaid Agency for neonates born to Medicaid-eligible mothers between January 1, 2010, and December 31, 2020. Data were analyzed in June 2022.
Exposure: A diagnosis of NAS within 30 days of birth.
Main outcomes and measures: Rate of NAS by demographic and birth characteristics, long-term costs attributable to NAS status and demographic and birth characteristics, and distribution of this expenditure over the enrollment period.
Results: A total of 346 259 neonates with Medicaid eligibility were born during the study period (mean [SD] gestational age, 38.4 [2.2] weeks; 50.5%, male), 4027 (1.2%) of whom had an NAS diagnosis within 30 days of birth. A larger percentage of neonates with an NAS diagnosis were male (52.7%) than in the group without NAS (50.5%). Neonates with NAS also weighed less at birth (mean difference, -212.0 g; 95% CI, -231.1 to -192.8 g) and had older mothers (mean difference, 3.4 years; 95% CI, 2.6-4.2 years). An NAS diagnosis had an estimated additional cost of $17 921 (95% CI, $14 830-$21 012) over the enrollment period, and this cost was not evenly distributed over that period.
Conclusions and relevance: In this cohort study of neonates born into the Alabama Medicaid population, those with an NAS diagnosis had a different demographic profile and a higher cost to state Medicaid agencies than those without NAS. These findings warrant further effort to reduce the occurrence of NAS.