Early Precursors of Mood Disorders in Young Children of Parents with Bipolar or Unipolar Disorder
At the 2020 meeting of the International Society for Bipolar Disorders, researcher Caroline Vandeleur presented findings from a 13-year study of children in Switzerland who have a parent with bipolar disorder or major depressive disorder. In contrast to findings from the US presented by Danella Hafeman, Vandeleur and colleagues found no evidence of psychopathology in 4 year-olds. They did find that in 7-year-olds, children of a parent with major depressive disorder were four times more likely to have a separation anxiety disorder. In an overall sample of 449 children with a mean age of 10 who were followed up for 13 years, major depression tended to be preceded by anxiety disorders. Participants who went on to be diagnosed with bipolar disorder had earlier symptoms of depression, subthreshold hypomania, conduct disorders, and drug abuse. These were especially common in those who had a parent with bipolar disorder.
Editor’s Note: These data indirectly confirm other observations in which children at high risk for mood disorders in the US showed earlier signs of psychopathology than those in other countries including the Netherlands and Canada.
Anxiety and Depressive Disorders Often Precede the Onset of Bipolar Disorder in Those At High Risk Due to Family History
At the 2012 meeting of the American Academy of Child and Adolescent Psychiatry (AACAP) meeting, Anne Duffy and Gabrielle A. Carlson sponsored a symposium on the association between anxiety and minor mood disorders and subsequent bipolar disorder in those at high risk. Researchers presenting at the symposium consistently found that there is a sequence in which young people at high risk for bipolar disorder develop increasingly severe illnesses: first anxiety, then mood disorders, then bipolar illness.
One difference: the incidence of childhood-onset bipolar disorders in those at high risk because a parent has the disorder was lower in Canada, Switzerland, and the Netherlands than it was in the US.
Duffy, a professor of psychiatry in Calgary, noted that bipolar disorder is highly heritable even though most adults with bipolar illness do not have a family history of bipolar illness among their first-degree relatives. She shared estimates that if one parent has bipolar disorder their offspring have a 5% lifetime risk of developing bipolar disorder. If both parents have bipolar disorder their offspring have a 25% risk of developing bipolar disorder and a 35% incidence of developing any affective disorder (although other data by Lapalme et al. suggest it may be as high as 60%).
Duffy found that when parents responded well to lithium, their children tended to do the same. Lithium-responsive patients tended to be those without anxiety disorder and substance abuse and who had classic bipolar episodes and clear well intervals between episodes. Read more
