Trends of Neonatal Abstinence Syndrome Epidemic and Maternal Risk Factors in Florida.

OBJECTIVE: This study aimed to examine secular trends of (i) maternal prescription opioid use in late pregnancy, (ii) neonatal abstinence syndrome (NAS) stratified by late maternal prescription opioid use, and (iii) maternal risk factors among NAS deliveries.

METHODS: Women with a live birth who were enrolled 90 days before and 30 days after delivery in Florida Medicaid Analytic Extract billing records linked to birth certificates from 2000 to 2010 were identified for the study. Changes in the annual prevalence of prescription opioid use during pregnancy were tested with use of the Cochran-Armitage trend test. Temporal trends of NAS deliveries were estimated with the use of Poisson regression and stratified by prescription opioid exposure in the last 90 days of pregnancy in the study period. To identify contributors to the increase in NAS cases, variations in prevalence of opioid dispensing, tobacco use, antidepressant use, and substance use disorder among NAS and non-NAS deliveries were examined.

RESULTS: There were 41,968 (9.4%) deliveries exposed to at least one opioid prescription in late pregnancy, and this rate remained stable from 2000 to 2010. Among prescription opioid-exposed deliveries, frequency of NAS increased from 1.6 to 25.2 per 1000 live births during the study period (p<0.05). Although the prevalence of maternal use of prescription opioid, tobacco, and antidepressants remained stable among NAS deliveries from 2000 to 2010, the prevalence of substance use disorder diagnoses increased substantially from 38.9% in 2000 to 67.9% in 2006 (p<0.05).

CONCLUSIONS: The prevalence of NAS increased dramatically whereas the prevalence of major risk factors, including maternal prescription opioid use, remained stable in Florida between 2000 and 2010. The increase in substance use disorder may be responsible for the sharp increase in NAS deliveries.