Children with depressed parents are at increased risk for developing mental health problems. Not all children of depressed parents should be categorized as being at-risk. However, both theory and research suggest that a child’s probability for poor adjustment increases as the number of risk factors that the child is exposed to increases.

Risk factors include how severe and chronic the parent’s depression is, whether the parent has anxiety disorders and problems with alcohol, similar disorders in the second parent, and divorce. Parental depression commonly occurs with adverse economic conditions, which is another risk factor.

A family history of depression is the strongest risk factor for depression in children, although how depression is transmitted is not well understood. Diathesis-stress theories suggest that a child’s sensitivity to stressful events depends on their genetic make-up, although how much the transmission of depression from a parent to a child child involves genes versus environmental stressors is unclear. Twin studies of depressive symptoms in children have reported significant genetic effects. Environmental influences are especially important for high depression scores and in children under 11 years of age.

Many researchers have reported an increased risk to children for a wide range of internalizing and externalizing disorders as well as depression. This lack of specificity can be explained, at least in part, by the presence of additional disorders in the parent, and by disorders in the second parent.

Internalizing and externalizing disorders, in addition to depression, are extremely common in children and adolescents. Comorbidity rates for depression and anxiety have been reported to be as high as 50 to 75 percent in clinically-based and community-based studies. Comorbidity rates for conduct disorder or oppositional defiant disorder and attention deficit/hyperactivity disorder have been reported to be 33 to 50 percent, although rates as high as 75 percent have been documented. The number of children and adolescents with diagnosable internalizing and externalizing disorders have been estimated at seven to 22 percent. A substantially higher percentage of children are expected to experience subclinical symptom levels.

— Dr. Patricia Turner, Registered Psychologist, Calgary, Alberta