A 3-Year Longitudinal Study of Risk for Bipolar Spectrum Psychopathology.

Current clinical and epidemiological research provides support for a continuum of bipolar psychopathology: a bipolar spectrum that ranges from subthreshold characteristics to clinical disorders. The present research examined risk for bipolar spectrum psychopathology at a 3-year follow-up assessment in a nonclinically ascertained sample of 112 young adults identified by the Hypomanic Personality Scale (HPS). Participants completed diagnostic interviews assessing bipolar psychopathology, borderline personality traits, substance use disorders, impulsivity, and psychosocial functioning. At the original assessment, 18 of the 112 participants met criteria for a bipolar spectrum disorder. At the follow-up, an additional 13 had developed bipolar spectrum disorders. A total of 58% of participants scoring in the upper quartile of the HPS qualified for bipolar spectrum disorders at the follow-up, including 27% with DSM–IV–TR disorders. The HPS predicted new cases and total number of cases of bipolar spectrum disorders, as well as total number of DSM–IV–TR bipolar disorders. The HPS also predicted hyperthymic temperament or history of hypomania, grandiose traits, impulsivity, substance use disorders, psychosocial impairment, and borderline traits. The majority of these effects were significant after removing participants with DSM–IV–TR bipolar disorders from the analyses, suggesting that the results were not driven by a subset of participants with clinical disorders. Overall, these results offer further support for the bipolar spectrum construct and the predictive validity of the HPS as a measure of bipolar spectrum psychopathology.