P3.P310: Predictors of positive urine toxicology screen in infants are minimally related to race

Background: Social determinants of health (SDoH) are nonmedical factors influencing health outcomes. Screening newborns for exposure to maternal substance use has legal, social and privacy implications, beyond affecting health outcomes. We previously reported that, among neonatal intensive care unit (NICU) admissions, infants of Black mothers were more likely to be screened that those of non-Black mothers, but this was explained by more infants meeting risk criteria for screening. This study is a focused review of the infants who received substance exposure screens at this institution.

Methods: Maternal and infant records for NICU admissions from 1/2021 to 12/2022 and all non-NICU admission inborn infants from 1/2021 to 12/2021 were reviewed for documented evidence of meeting substance use screening criteria. Basic demographic data including NICU admission, inborn status, gender, race/ethnicity, home zip code, insurance status, gestational age and birth weight were collected on all infants. At our institution, “mandatory” criteria expected to trigger screening in all affected infants were maternal illicit substance use, limited prenatal care ( < 5 visits), and placental abruption without preeclampsia. We assessed whether infants had a urine drug screen for illicit substances performed, whether they met criteria, and evaluated limited SDoH. The charts of the 206 infants who received screens were then analyzed for additional factors that may have affected the decision to obtain a screen or correlated with a positive result. Data were analyzed using Fisher exact test with relative risk and confidence intervals. Positive predictive value of various screening criteria were calculated.

Results: We assessed 4196 infant-mother pairs, among whom 206 infants received substance exposure screens. Infants screened were more likely to be admitted to the NICU, be Black, have public insurance, or have a home address in one of the 5 poorest zip codes in the metropolitan area (Table 1). All infants screened for abruption only had a negative screen. All cocaine positive infants had a birth parent with documented polysubstance use. These parents often also had limited or no prenatal care, housing instability, and previous Child Protective Services involvement (Table 2)

Conclusion: SDoH are correlated with which infants receive a substance exposure screen, even in the setting of being indicated by meeting screening guidelines. Black infants are screened more frequently but with a lower relative risk than public insurance or lower income, with marginalization as the underlying SDoH that likely drives much of who is selected for screening. Abruption and limited prenatal care in isolation are not correlated with positive infant screens but birth parent polysubstance use in combination with other factors is present in every infant that screened cocaine positive. This suggests that given a goal of screening includes identifying families at high risk for social instability, history may be sufficient.