Longitudinal Assessment of Hospital Utilization Among Infants with Neonatal Abstinence Syndrome and Mothers with Opioid Use, Florida 1998-2018

Over the past few decades, maternal opioid use and Neonatal Abstinence Syndrome (NAS) have significantly increased. However, few studies have examined prevalence trends by sociodemographic variables. Therefore, the first aim of my dissertation was to determine the prevalence by year for each outcome for the total sample and by maternal race/ethnicity, education level, and insurance type. Prenatal opioid exposure (POE) poses neonatal risks including Neonatal Abstinence Syndrome (NAS) and studies suggest the effects may extend through childhood. However, there are critical gaps in literature on the long-term developmental outcomes of opioid-exposed infants by presence of NAS. Therefore, the second aim of my dissertation was to examine the association between POE and/or NAS and the risk of all-cause, injury, and mental health hospital encounters from birth through 5 years old. The postpartum period presents challenges for women with prenatal opioid use such as experiences of stigma, limited access to healthcare, and adverse health outcomes. However, previous studies were limited to 90-day outcomes and did not examine reasons for encounter. Therefore, the third aim of my dissertation was to examine the association between prenatal opioid use and all-cause, opioid, and mental health hospital encounters through 5-years post-delivery. We conducted a retrospective cohort study using a statewide, population-based administrative dataset of Florida resident live births from 1998 to 2017 (N=3,924,412). Maternal opioid use and NAS were identified using primary or secondary diagnoses including ICD-9-CM (779.5) or ICD-10-CM (P96.1) for NAS and a wide range of CM codes for maternal opioid use including opioid dependence, opioid abuse, opioid use, overdose, and adverse effects of opioid use. We also included maternal, infant, and hospital level covariates. Joinpoint regression was used to identify statistically significant changes in the trends of each opioid-related outcome. To examine the associations of hospital utilization for the infant/mother, modified Poisson regression with robust error variance was used to calculate crude (cRR) and adjusted relative risks (aRR) and 95% confidence intervals (CI) while accounting for clustering by the birth/delivery hospital. Maternal opioid use was identified in 1% (n=23,525) of the total sample, of which, 60% were diagnosed with NAS. There was a significant increase in maternal opioid use from 2001 to 2015 with a 40.4% (95% CI: 21.67, 62.10) annual increase from 2007 to 2010. NAS increased from 2.6 to 70.0 per 10,000 from 1998 to 2018. Maternal opioid use and NAS were most common among non-Hispanic White mothers with Medicaid insurance and less than a high school education for most of the study period. We found significant differences in the risk of all-cause hospital encounter for all infants with POE between 0-30 days and 31-365 days (p We also found significant differences in the risk of all-cause, opioid-related, and mental health related hospital encounters for mothers with prenatal use from delivery through 5 years (p Our study found that maternal opioid use and NAS increased significantly from 1998-2015 and remained prevalent in Florida through 2018. Overall, we found that both mothers and infants affected by prenatal opioid use have high long-term risks of hospitalization, mental health diagnoses, and injury/abuse. Our study highlights the importance of long-term social and clinical support for affected mother-infant dyads through improving postpartum access to healthcare and MOUD, reducing stigma around NAS and maternal opioid use to promote well-child visits and OUD treatment adherence, and targeted social service and parenting interventions. This study provides insight on the consequential epidemiology of prenatal opioid use for mothers and children to inform and support future evidence-based initiatives