When Moms Get Depressed, Part Two: The Environmental Influence on Kids
In my last post, I discussed a recent study that provided new evidence on how kids with depressed moms are at risk for depression. Another study (from the same issue of the Journal of the American Academy of Child and Adolescent Psychiatry) has provided novel evidence that some of this risk is environmental. First I’ll explain what they found — and then discuss why it’s important.
The researchers examined families in which children were conceived by assisted reproduction. In some families, the mom was biologically related to her child; in others, she wasn’t. From the scientific perspective, this is a modern twist on the adoption study method. The study could then look at the links between maternal depression and symptoms of depression in their kids when there was — and wasn’t — a genetic relationship between them.
They found significant associations between moms’ levels of depressive symptoms and those in their children, both in childhood and in early adolescence. These associations were not influenced by the genetic relationship — they were similar whether or not the mom was the biological mom. The conclusion is that there is an enviromental effect of being exposed to mom’s depression.
I feel that it is really important to highlight environmental pathways these days. So much of the scientific climate has been directed to genetic effects (on nearly everything). Certainly genes will play a role in determining which children and adolescents go on to suffer from recurrent or severe depression. There is also a long history of interest in “gene-environment” interaction — some youth may be genetically resilient to exposure, whereas others may be highly sensitive to it. All that said, there have been a number of studies over the last two decades that demonstrate purely environmental effects on depressive symptoms in children and young adolescents (I’ve done some of this work myself). And the important thing about that replicated finding is that is suggests there may be immediate ways of changing the environment to improve the emotional well-being of kids who have a depressed mom.
In my next post, I will focus on research that shows what happens to kids when their moms get treated for depression. Teaser: it’s a good thing for them.