Children of people with bipolar disorder at higher risk to develop ADHD, new study says

From Reuters:

NEW YORK -- Your preschool child is throwing a fit: is it just a temper tantrum, or could it be an early sign of something more serious, such as attention deficit hyperactivity disorder (ADHD) or oppositional defiant disorder? The answer may lie in your own mental health.

According to a new study, young children whose parents have bipolar disorder -- a mental illness marked by severe mood swings from depression to mania -- have an eight-fold higher risk of ADHD relative to young children of mentally healthy parents. They also have a six-fold high risk of having two or more mental disorders.

The study, led by Dr. Boris Birmaher of the Western Psychiatric Institute and Clinic in Pittsburgh, Pennsylvania compared 121 children ages 2 to 5 from 83 parents with bipolar disorder with 102 children of the same age from 65 comparison group parents with no history of bipolar disorder.

The researchers excluded parents who had ever been diagnosed with schizophrenia, mental retardation, or mood disorders stemming from substance abuse, medications, or medical conditions.

Their results, published in the American Journal of Psychiatry, point to an elevated risk for ADHD and other psychiatric disorders among children of parents with bipolar disorder.

And while only three children of bipolar parents had mood disorders, children of parents with bipolar disorder, especially those with ADHD and oppositional defiant disorder, had significantly more severe manic and depressive symptoms than comparison children.

While diagnosing a preschooler with mania is a controversial endeavor, the investigators point to previous studies showing that preschoolers can indeed be diagnosed reliably with a psychiatric disorder, including bipolar disorder, as young as age 2.

They acknowledge in their report that parents with bipolar disorder may witness behaviors in their own children that remind them of their own symptoms. Such watchful anxiety may be justifiable, as "The single largest risk factor for the development of bipolar disorder is a positive family history of the disorder," the investigators note.

As with most medical issues, there is a benefit of early detection, Birmaher and colleagues note. Psychosocial interventions aimed at helping preschool children regulate their mood, they point out, have been found to be useful in preschoolers with disruptive behavior disorders and in older children with signs of mood disorders.

And effective treatment of mental health problems in parents "may diminish the severity of, and perhaps delay or prevent the new onset of," similar problems in preschool children of parents with bipolar disorder.