Children and teens of parents with bipolar disorder appear to have an increased risk of early-onset bipolar disorder, mood disorders and anxiety disorders, according to a report in the March issue of Archives of General Psychiatry, one of the JAMA/Archives journals.

As many as 60 percent of patients with bipolar disorder experience symptoms before age 21, according to background information in the article. Identifying the condition early may improve long-term outcomes, potentially preventing high psychosocial and medical costs. Having family members with bipolar disorder is the best predictor of whether an individual will go on to develop the condition, the authors note. "Therefore, carefully evaluating and prospectively following the psychopathology of offspring of parents with bipolar disorder and comparing them with offspring of parents with and without non-bipolar disorder psychopathology, are critical for identifying the early clinical presentation of bipolar disorder," they write.

Boris Birmaher, M.D., of Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center, and colleagues compared 388 offspring (ages 6 to 18) of 233 parents with bipolar disorder to 251 offspring of 143 demographically matched control parents. Parents were assessed for psychiatric disorders, family psychiatric history, family environment and other variables, and were also 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 control parents, children of parents with bipolar disorder had an increased risk of having a bipolar spectrum disorder (41 or 10.6 percent vs. two or 0.8 percent) and having any mood or anxiety disorder. Children in families where both parents had bipolar disorders also were more likely than those in families containing one parent with bipolar disorder to develop the condition (four of 14 or 28.6 percent vs. 37 of 374 or 9.9 percent); however, their risk for other psychiatric disorders was the same as offspring of one parent with bipolar disorder.

"Consistent with the literature, most parents with bipolar disorder recollected that their illness started before age 20 years and about 20 percent had illness that started before age 13 years," the authors write. "In contrast, most of their children developed their first bipolar disorder episode before age 12 years, suggesting the possibility that parents were more perceptive of their children's symptoms early in life or perhaps that bipolar disorder has more penetrance and manifests earlier in new generations."

The findings have important clinical implications, they note. "Clinicians who treat adults with bipolar disorder should question those who are parents about their children's psychopathology to offer prompt identification and early interventions for any psychiatric problems that may be affecting the children's functioning, particularly early-onset bipolar disorder," they continue. 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 offspring of those with bipolar disorder.

This work was supported by a grant from the National Institute of Mental Health. Dr. Birmaher has participated in forums sponsored by some pharmaceutical companies (Solvay, Abcomm Inc. and Jazz Pharmaceuticals Inc.). Co-author Dr. Kupfer has served on the advisory boards of Pfizer Inc., Eli Lilly and Co., Forest Pharmaceuticals Inc., F. Hoffman-La Roche Ltd. and Solvay/Wyeth Pharmaceuticals and has been a consultant to Servier Amerique.