Affective Temperament Traits Measured by TEMPS-A and Their Associations with Cognitive Functions among Offspring of Parents with Bipolar Disorder with and without Subthreshold Symptoms

Background: To our knowledge, there have been no studies that have examined affective temperament traits in offspring of parents with bipolar disorder (BD). The aim of this study was to identify affective temperamental characteristics and their relationships with cognitive functions in BD offspring. Methods: A group of BD offspring were enrolled in this study. Subthreshold symptoms were used to categorize participants as either symptomatic offspring (SO) (n=60) or asymptomatic offspring (AO) (n=52). Healthy controls (HCs; n=48) were also enrolled for comparison. We used the Chinese Short Version of Temperament Evaluation of Memphis, Pisa, Paris, and San Diego, Auto-questionnaire (TEMPS-A) to measure temperament traits, and MATRICS Consensus Cognitive Battery (MCCB) to measure cognitive functions. Results: We observed higher cyclothymic, irritable, depressive and anxious temperament scores in SO than AO when compared to HCs. In BD offspring (SO and AO), cyclothymic individuals performed better in processing speed and verbal learning than depressive individuals and better in attention/vigilance than irritable and anxious individuals; hyperthymic individuals performed better in processing speed than depressive individuals. We also observed that a higher cyclothymic score was associated with better verbal learning and verbal fluency, a higher hyperthymic score was associated with better processing speed and verbal learning; while a higher depressive score was associated with worse processing speed, verbal learning and verbal fluency and a higher irritable score was associated with worse attention/vigilance. Conclusions: The relationships between cognitive functions and measures of temperament suggest that these features may share neurobiological substrates and appear to be heritable.