Adoption during infancy is associated with a lower rate of adulthood depression compared with adults with a long history of foster care, according to research published in BMJ Paediatrics Open.
To determine whether the risk for adulthood depression differed by care arrangements, researchers conducted a register study using Swedish national cohorts. Participants were divided into groups of children raised in adoptive homes or foster homes before age 2 years and a comparison majority population group. Using Cox regression models, researchers estimated hazard ratios of prescribed antidepressant medication and specialized psychiatric care with diagnosed depression in adulthood.
The findings showed that long-term foster care had the highest hazard ratio for antidepressive medication use (2.07) and psychiatric care for depression in adulthood (2.85), even when adjusted for age and sex.
This is 2-fold the rate of depression indicators among the general population. Adults raised by adoptive parents were more similar to the general population, with antidepressive medication hazard ratios of 1.19 for domestic adoptees and 1.13 for international adoptees.
Early adoption during infancy was associated with a significantly lower risk for adult depression than foster care.
The study was limited by the lack of information about familial risk factors; that is, hereditary, fetal, and early childhood exposures in the study groups, and the reason why children were taken into foster care or adopted.
The researchers concluded, “This study suggests that early adoption can protect children from some or even all of the risk of depression associated with early childhood adversity.”
The study also highlights the importance of educational support for children in foster care. Researchers recommended subsequent studies to examine the foster care group to clarify the protective effect of placement stability.
Hjern A, Palacios J, Vinnerljung B. Can adoption at an early age protect children at risk from depression in adulthood? A Swedish national cohort study. BMJ Paediatr Open 2018;2(1):e000353.