Adverse childhood experiences among children of parents who are refugees affected by trauma in Denmark: a register-based cohort study.

Background: Children in families who are refugees might experience more adversities than their peers. Adverse childhood experiences (ACEs) are well known risk factors for poorer adulthood health and adjustment. The risk of ACEs for children with a parent who is a refugee affected by trauma is unknown. We aimed to estimate the hazard of individual and cumulative ACEs using a unique sample of children with parents who are refugees affected by and seeking treatment for trauma and population level data.

Methods: This was a register-based cohort study carried out in Denmark. All children aged 0-15 years, residing in Denmark between Jan 1, 1990, and Dec 31, 2016, were followed up from birth or migration into the country to their 15th birthday. We linked data from the Danish Civil Registration System, the Danish National Patient Register, the Danish Psychiatric Central Research Register, the Employment Classification Module, the Register of Causes of Death, and the Income Statistics Register to investigate ten ACE categories (parental: natural and unnatural death, serious mental illness, substance use disorder, somatic illness, and disability; child: residential instability, family disruption, poverty, and stressors) and the cumulative number of ACE categories for children with a parent from a refugee-sending country and children with a parent who is a refugee in treatment for trauma. The main outcome was the hazard ratio (HR) of the individual and cumulative ACEs among children with a parent from a refugee-sending country and children with a parent who is a refugee affected by trauma, compared with the general population of children in Denmark, both adjusted and unadjusted for parental country of origin.

Findings: 2 688 794 children were included in the study, 252 310 of whom had parents from refugee-sending countries. 11 603 children had parents affected by trauma and seeking treatment, of whom 1163 (10%) migrated to Denmark before their second birthday and 10 440 (90%) were born in Denmark. Compared with the general population of children in Denmark, the hazard for most ACEs was significantly higher for both children with parents from a refugee-sending country and children with parents who are refugees affected by trauma. For children with a parent from a refugee-sending country, the highest HR was related to the child living in relative poverty for 3 years (3·62 [95% CI 3·52-3·73]). After adjusting for parental country of origin, the hazards for five ACEs were significantly greater for children of parents who are refugees affected by trauma compared with the remaining children of parents from the same countries. The highest HR for this child group was for parental serious mental illness (1·98 [1·85-2·12]). The hazard for experiencing multiple ACEs was significantly higher for both child groups compared with the general population.

Interpretation: Our findings suggest that children with parents from refugee-sending countries have a higher rate of several ACEs compared with the general population. Furthermore, having a parent who is a refugee affected by trauma and seeking treatment seems to be an independent risk factor for poorer health and adjustment in adulthood. This study informs decision makers and caregivers that there might be much added value in addressing needs within the whole family, as opposed to only attending to the parent who is seeking treatment.

Funding: The Lundbeck Foundation.