Many of us know that once we start talking about our experiences with a Perinatal Mood and Anxiety Disorder, those around us begin to hear reflections of their own journeys in our words. Sometimes, that may even be a family member such as a sister or a mother. But is a Perinatal Mood & Anxiety Disorder a heritable illness? A recent study’s results claims that yes, it is.
Dr. Ruta Nonacs at Massachusetts General Hospital’s Center for Women’s Mental Health covers it quite well in her blog post here.
What is heritability? If you want to get into the research aspect of it, the University of Colorado has a nifty short and simple explanation here (complete with activities). For a simple and straight forward definition, heritability, according to Merriam Webster, is the proportion of observed variation in a particular trait (as height) that can be attributed to inherited genetic factors in contrast to environmental ones.
The study referenced by Dr. Nonacs is, as she puts it, “to date, the largest genetic epidemiological study of perinatal depression.”
A quick look at the numbers, according to Dr. Nonac’s post:
Using data from the twins, the heritability of perinatal depression was estimated at 54% (95% CI=35%?70%), with the remaining variance attributable to non-shared environmental factors (46%; 95% CI=31%?65%). Using data from the siblings, the heritability of perinatal depression was estimated at 44% (95% CI=35%?52%) and the heritability of non-perinatal depression at 32% (95% CI=24%?41%). The authors estimated that about one-third of the genetic contribution was unique to perinatal depression and not shared with non-perinatal depression, suggesting only partially overlapping genetic etiologies for perinatal depression and non-perinatal depression.
What does all of this mean exactly?
It means a shift in research should occur, one which focuses on the genetics of those who struggle with perinatal mood and anxiety disorders instead of those who do not.
Hopefully this is something that will happen much sooner rather than later. For now, though, it’s a huge step closer to understanding the nuances and complexities of a very difficult illness which strikes new mothers and sends ripples through their entire families.
{pic source: pixbay}
I am a broken record to those who know me, but pregnancy complications will create a dynamic to increase risk. For example, Hyperemesis Gravidarum and its longterm malnutrition and frequent dehydration increase risk of PMADs…and HG moms have a VERY high incidence of PTSD. When it comes to environmental factors, HG and other complications need to be considered.
Thank you for summarizing and linking research, Lauren. Worth investigating would be whether the University of Minnesota Twin Studies look at PMADs.