Hypomanic, cyclothymic and hostile personality traits in bipolar spectrum illness: a family-based study

To examine hypomanic, cyclothymic and hostile personality traits in a large, euthymic, family-based group of individuals with bipolar disorder (BPD) and their affectively ill and healthy relatives. To test whether these traits follow a distribution with the most "pathological" scores in the bipolar disorder I (BPD I) group and the least "pathological" scores in the unaffected relatives.

Two-hundred and ninety-six individuals from 47 bipolar disorder families were administered a battery of personality questionnaires (Temperament Evaluation of Memphis, Pisa, Paris, and San Diego; Temperament and Character Inventory; Affective Neuroscience Personality Scale; Hypomanic Personality Scale; Borderline Traits Questionnaire) as well as a self-rating depression (Beck Depression Inventory) and mania (Altman Self-Rating Mania) scale. Out of the 296 participants, 57 were diagnosed with BPD I, 24 with bipolar disorder II (BPD II), 58 with recurrent major depression (MDE-R), 45 had one previous depressive episode (MDE-S), and 86 were unaffected. Twenty six individuals had another DSM-IV diagnosis.

The BPD I group displayed elevated hypomanic, cyclothymic and hostile traits. These traits were also characteristic of the BPD II group but were less salient in the MDE-R group. The MDE-S group did not differ significantly from unaffected relatives. Hypomanic personality characteristics were clearly elevated in both BPD groups and differentiated BPD from major depressive disorder (MDD) individuals.

Our results provide preliminary support for the hypothesis that temperament is a genetically quantitative trait.