Association between out-of-home care and mortality in children with prenatal drug exposure: a retrospective population-based cohort study

Objective: To determine if out-of-home care (OOHC) reduces the risk of death in children with prenatal drug exposure (PDE). Design: Population-based cohort study. Setting: New South Wales, Australia. Patients: Children with PDE, born between 2001 and 2020 and discharged alive after birth. Exposure: PDE was defined as intrauterine exposure to maternal use of drugs of addiction, categorised into (1) neonatal abstinence syndrome (NAS) (n=5978); (2) exposure to maternal drugs of addiction, but not meeting diagnostic criteria for NAS (n=12 162); and (3) exposure to maternal exclusive tobacco smoking (n=187 827). Subanalyses by type of maternal drug use (opioids, stimulants and cannabis) were conducted. Main outcome measures: Multivariate regression analyses of linked administrative data were used to determine the primary outcome of death after birth hospital discharge. Causal mediation analyses assessed the mediating effect of OOHC between PDE and mortality. Results: Compared with no exposure, PDE was associated with a higher risk of childhood death. Risks were highest for infants with NAS (HR=4.20, 95% CI=3.23 to 5.44), followed by infants with PDE but no NAS diagnosis (HR=2.53, 95% CI=2.01 to 3.18). Mediation analyses demonstrated a natural indirect protective effect of OOHC in reducing risk of death (NAS: OR=0.5, 95% CI=0.5 to 0.5; PDE but no NAS diagnosis: OR=0.8, 95% CI=0.8 to 0.8). Subanalyses demonstrated a protective effect of OOHC for three types of maternal drug use (opioids: OR=0.7; stimulants: OR=0.8; cannabis: OR=0.9). Conclusions: Any OOHC intervention was associated with reduced risk of death for children with PDE, emphasising the importance of strengths-based, culturally-sensitive support for this vulnerable population.