Risk of emotional disorder in offspring of depressed parents: gender differences in the effect of a second emotionally affected parent.

In offspring of depressed parents a second parent with emotional problems is likely to increase risk of emotional disorder. This effect may however differ between sons and daughters and between offspring of depressed fathers and offspring of depressed mothers. In adolescent and young-adult offspring of parents with major depressive disorder, this study examined the effects of a second affected parent, offspring gender, gender of the depressed parent and their interactions on risk of depression and anxiety disorder. We found that daughters had a higher risk of depression and anxiety than sons and that offspring of depressed mothers had a higher risk of anxiety than offspring of depressed fathers. In addition to these main effects, we found an interaction between parent and offspring gender inasmuch that sons of depressed fathers had the lowest risk of depression and anxiety relative to the other groups. A second affected parent tended to increase risk of depression and significantly increased risk of anxiety. However, this effect of a second affected parent on offspring anxiety was most prominent in daughters when the second affected parent was the father, whereas risk in sons did not increase if the father was affected as well. Our results indicate that paternal and maternal depression similarly and additively increase daughters' risk of emotional disorder, but that sons' risk only increases with maternal depression. Intergenerational transmission of emotional disorder seems strongest when the female gender is involved, either in the form of a daughter or a depressed mother. Copyright 2007 Wiley-Liss, Inc.