Affective lability in offspring of parents with major depressive disorder, bipolar disorder and schizophrenia.

Affective lability, defined as the propensity to experience excessive and unpredictable changes in mood, has been proposed as a potential transdiagnostic predictor of major mood and psychotic disorders. A parental diagnosis of bipolar disorder has been associated with increased affective lability in offspring. However, the association between affective lability and family history of other mood and psychotic disorders has not been examined. We measured affective lability using the self- and parent-reported Children's Affective Lability Scale in a cohort of 320 youth aged 6-17 years, including 137 offspring of a parent with major depressive disorder, 68 offspring of a parent with bipolar disorder, 24 offspring of a parent with schizophrenia, and 91 offspring of control parents. We tested differences in affective lability between groups using mixed-effects linear regression. Offspring of a parent with major depressive disorder (β = 0.46, 95% CI 0.17-0.76, p = 0.002) or bipolar disorder (β = 0.47, 95% CI 0.12-0.81, p = 0.008) had significantly higher affective lability scores than control offspring. Affective lability did not differ significantly between offspring of a parent with schizophrenia and offspring of control parents. Our results suggest that elevated affective lability during childhood is a marker of familial risk for mood disorders.