Lifetime psychiatric disorders in school-aged offspring of parents with bipolar disorder: the Pittsburgh Bipolar Offspring study.

CONTEXT: Whether offspring of parents with bipolar disorder (BP) are at specifically high risk to develop BP and other psychiatric disorders has not been adequately studied.

OBJECTIVE

To evaluate lifetime prevalence and specificity of psychiatric disorders in offspring of parents with BP-I and BP-II.

DESIGN

Offspring aged 6 to 18 years who have parents with BP and community control subjects were interviewed with standardized instruments. All research staff except the statistician were blind to parental diagnoses.

SETTING

Parents with BP were recruited primarily through advertisement and outpatient clinics. Control parents were ascertained by random-digit dialing and were group matched for age, sex, and neighborhood to parents with BP.

PARTICIPANTS

Three hundred eighty-eight offspring of 233 parents with BP and 251 offspring of 143 demographically matched control parents.

MAIN OUTCOME MEASURES: Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) Axis I disorders.

RESULTS

Adjusting for demographic factors, living with 1 vs both biological parents, both biological parents' non-BP psychopathology, and within-family correlations, offspring of parents with BP showed high risk for BP spectrum disorders (odds ratio [OR] = 13.4; 95% confidence interval [CI], 2.9-61.6) and any mood (OR = 5.2; 95% CI, 2.3-11.4), anxiety (OR = 2.3; 95% CI, 1.3-4.0), and Axis I (OR = 2.2; 95% CI, 1.5-3.3) disorders. Offspring of parents with BP with high socioeconomic status showed more disruptive behavior disorders and any Axis I disorders than offspring of control parents with high socioeconomic status. Families in which both parents had BP had more offspring with BP than families with only 1 parent with BP (OR = 3.6; 95% CI, 1.1-12.2). More than 75.0% of offspring who developed BP had their first mood episode before age 12 years, with most of these episodes meeting criteria for BP not otherwise specified and, to a lesser degree, major depression.

CONCLUSIONS

Offspring of parents with BP are at high risk for psychiatric disorders and specifically for early-onset BP spectrum disorders. These findings further support the familiality and validity of BP in youth and indicate a need for early identification and treatment.