Child and adolescent anxiety as a risk factor for bipolar disorder: A systematic review of longitudinal studies

Abstract

Objectives: Several studies have suggested that anxiety disorders in childhood and adolescence often precede the onset of bipolar disorder. We therefore systematically reviewed the relationship between child and adolescent anxiety and later bipolar disorder. Methods: Online databases (Medline [for Ovid], EMBASE and PsychINFO) were searched for original, peer-reviewed studies examining the relationship between child and adolescent anxiety and later bipolar disorder. Studies in both community samples and bipolar offspring samples were included. Results: A total of 16 studies were included in the review. The results were broadly consistent and revealed that child and adolescent anxiety disorders are associated with later bipolar disorder in community samples. In bipolar offspring, child and adolescent anxiety disorders are a marker of increased risk and predict the onset of bipolar disorder and other major mood disorders. Conclusions: There is evidence that anxiety disorders in childhood and adolescence increase the risk of later bipolar disorder. Anxiety disorders may be a useful target for early intervention in those at high-risk of bipolar disorder.