Cumulative risk factors for injuries and poisoning requiring hospital care in youth with prenatal substance exposure: A longitudinal controlled cohort study

Aim: To investigate whether the youth with prenatal substance exposure (PSE) (aged 15-24 years, n = 615) had been in hospital care more often due to injuries and poisoning in comparison with unexposed matched controls (n = 1787). Methods: Data from medical records (exposure) and national health and social welfare registers (outcome and confounders) were combined and youths were monitored from birth until either outpatient or inpatient hospital care for injury or poisoning, death or the end of the study period (December 2016). Cox regression models were used in the analyses accounting for associated child and maternal risk factors. Results: Half (50.4%) of the exposed group and 40.6% of controls had been in hospital care due to injury or poisoning during the follow-up (p < 0.001). The difference between groups was diminished after controlling for postnatal child and maternal risk factors (hazard ratio [HR] = 0.88, 95% confidence interval [CI] 0.72-1.07, p > 0.05). Cumulative adversity, especially out-of-home care in combination with a diagnosed attention or behavioural dysregulation problem, posed the highest risk in both groups (exposed: HR = 1.65, 95% CI 1.24-2.19, p < 0.001; controls: HR = 1.84, 95% CI 1.33-2.56, p < 0.001). Conclusion: Hospital care for injury and poisoning is more common in youth with PSE, but this is largely explained by the related postnatal child and maternal factors. Long-term support to families with maternal substance abuse problems could prevent injury and poisoning among youth with PSE.