Objective: For nearly 5 years a prospective high risk cohort study was carried out in the Netherlands among adolescent offspring of parents with bipolar disorder (BD). The purpose of this study was to determine the prevalence of psychopathology, specifically mood disorders, in adolescents and young adults with a bipolar parent.
Method: At first and second measurement 140 and 132 children of bipolar parents, respectively, were psychiatrically evaluated with a semi-structured psychiatric interview (K-SADS-PL). At follow up (third measurement), nearly 5 years later, lifetime DSM IV diagnoses were obtained from the SCID interview for 129 subjects (aged 16--26 years).
Results: Compared with the first measurement, the lifetime prevalence of BD increased from 3 to 10% at follow up. In addition, the lifetime prevalence of overall mood disorders increased to 40% and of overall psychopathology to 59%. All subjects except for one with BD, debuted with a unipolar mood disorder with a mean of 4.9 (SD 3.4) years prior to the first (hypo)manic episode.
Conclusion: At follow up, we noticed an increase in BD onset, while a further increase could be expected. In addition, we found that a unipolar depression in bipolar offspring is a risk factor for, and at the same time the first sign of, the development of BD.