Children of Parents With Bipolar Disorder at Risk of ADHD and Early Onset Bipolar, Study Suggests

Children who have a parent with bipolar disorder are more likely to develop attention-deficit/hyperactivity disorder (ADHD) during their preschool years than children with no family history of bipolar disorder, reports a study in Journal of the American Academy of Child and Adolescent Psychiatry. The study also found that these children were more likely to develop symptoms of bipolar disorder as they grew older.

“[Bipolar disorder] symptoms were scarce during the preschool years and increased throughout [early adolescence],” wrote Boris Birmaher, M.D., of the University of Pittsburgh School of Medicine and colleagues. “Developing early interventions to delay or, ideally, prevent [bipolar disorder] onset are warranted.”

Birmaher and colleagues recruited 116 children who had a parent with either bipolar I or II disorder (BD-I/II parents), 53 children of parents with a non-bipolar psychiatric disorder (non-BD parents), and 45 children of parents with no psychiatric disorder (healthy parents) for the study. All children were between the ages of 2 and 5 years at the start of the study and were periodically assessed for about 10 years using the Schedule for Affective Disorders and Schizophrenia for School-Age Children, Present and Lifetime Version (KSADS-PL).

The researchers found that the children of BD-I/II parents were significantly more likely to have ADHD by age 5 (21.6% of children) than children of non-BD parents (3.8%) and children of healthy parents (2.2%). After age 5, children of BD-I/II parents and non-BD parents showed no statistical difference in rates of non-bipolar psychiatric disorders. However, compared with children of healthy parents, children of BD-I/II parents had elevated rates of anxiety, ADHD, and behavior problems after age 5.

During the study period, 17 of the children of parents with BD-I/II (about 15%) were diagnosed with bipolar disorder; four children developed BD-I/II and 13 developed BD-Not-Otherwise-Specified (BD-NOS), with an average age of onset of 11.4 and 7.4 years, respectively. (BD-NOS is typically diagnosed in people who show bipolar mood swings but the timing and/or intensity do not meet the full criteria of BD-I or BD-II.) None of the children in the other groups received a diagnosis of bipolar disorder during the study.

“Given that youth with BD-NOS exhibit as much psychosocial impairment, suicide risk, substance abuse, comorbid disorders, and family history of BD as youths with BD-I/II, and are at very high risk to transition into BD-I/II (particularly if they have family history of BD), the diagnosis of BD-NOS warrants significant clinical consideration,” Birmaher and colleagues wrote.

The researchers looked over the data to see which factors might help predict the youth who would develop bipolar disorder; the only significant risk factors they identified were an ADHD diagnosis before age 6 and having parents with early onset bipolar disorder.

To read more on this topic, see the Psychiatric News article “Study Sheds Light on Trajectory of Developing Bipolar Disorder.”