Preschool Children of Bipolar Parents Have Eightfold Increase in Risk for ADHD, Pitt Study Finds

Issue Date: 
February 15, 2010
Boris BirmaherBoris Birmaher

Preschool children of parents with bipolar disorder have an eightfold increase in the risk for attention deficit hyperactivity disorder (ADHD) and significantly higher rates of multiple psychiatric disorders compared with children of parents who don’t have the mental illness, according to a University of Pittsburgh School of Medicine research study to be published in the March issue of the American Journal of Psychiatry.

“Studies already have shown that the children of bipolar parents are far more likely to develop the disease, although typically not in the preschool years. By identifying ADHD and other developmental issues in this group, we can treat them early and potentially prevent full-blown development of bipolar disorder,” said Boris Birmaher, lead author of the study and Endowed Chair in Early Onset Bipolar Disease and professor of psychiatry in the University of Pittsburgh School of Medicine. Birmaher is also codirector of Child and Adolescent Bipolar Services at Western Psychiatric Institute and Clinic of UPMC.

The study is currently available online at

According to previously published results from the Pittsburgh Bipolar Offspring Study (BIOS), having parents with bipolar disorder is the best predictor of whether those parents’ children will develop the condition. However, until now, little has been known about the effects of parents’ bipolar disorder on their preschool-age children.

For the current study, the Pitt researchers compared two groups of children and parents. The first group had 121 children, ages 2 to 5, of 83 parents with bipolar disorder. (Of those parents, only two families had both a mother and father with bipolar disorder.) The second group was a demographically matched control group comprising 102 offspring of 65 parents without bipolar disorder.

Parents were assessed for psychiatric disorders, family mental health history, family environment, and exposure to negative life events. They also were interviewed about their children. Children were assessed directly for bipolar disorder and other psychiatric disorders by researchers who did not know their parents’ diagnoses.

Compared with the offspring of parents in the control groups, children with bipolar parents had an eightfold increase in the risk of having ADHD, as well as a sixfold increase in the risk of having two or more other psychiatric disorders. Although only three children had clinically certified full-blown mood disorders, children of bipolar parents, particularly those with ADHD or ODD (oppositional defiant disorder) had more subclinical manic and depressive symptoms when compared with children in the control group.

“Because BIOS is prospectively following all of these children, we will be able to address their developmental issues and delineate the types and severity of symptoms that may predict a possible conversion to bipolar disorder,” said Birmaher. “Also, because almost 70 percent of the children of parents with bipolar disorder in our study did not have any diagnosable psychiatric illnesses and very few appeared to be on the cusp of developing mood disorders, we believe there is a window of opportunity for prevention in the high-risk group of kids.”

The researchers note that these findings have important implications. “Clinicians who treat adults with bipolar disorder should question them about their children’s psychopathology to offer prompt identification and early interventions for any psychiatric problems that may be affecting the children’s functioning,” noted Birmaher. “Further studies are needed to help determine the clinical, biological, and genetic risk factors that may be modified to prevent the development of psychiatric disorders in the children of those with bipolar disorder.”

The Pittsburgh Bipolar Offspring Study was supported in part by funding provided by the National Institute of Mental Health.