Affective instability, family history of mood disorders, and neurodevelopmental disturbance.

The association between affective instability and both family history of mood disorders and signs of neurodevelopmental disturbance was examined in a sample of 303 adults. Affective instability was measured using the borderline personality disorder "affective instability due to a marked reactivity of mood" diagnostic criterion as assessed dimensionally using the Personality Disorder Interview--IV. Participants were interviewed concerning family history of mood disorders, with family history coded using the Family History Research Diagnostic Criteria. Minor physical anomalies, inconsistent hand use, and dermatoglyphic asymmetries were used to index neurodevelopmental disturbance. Affective instability was associated with elevated rates of family history of mood disorders, particularly among individuals who exhibited inconsistent hand use and greater minor physical anomalies. These associations could not be accounted for by shared variance with age, gender, negative affect, or personal history of mood disorders.