Bipolar disorder and anxiety disorders.

BACKGROUND Anxiety disorders are common in patients with bipolar disorder and show considerable influence on the course of the disease and response to treatment. METHOD We conducted a series of literature searches using key words, such as bipolar disorder and anxiety disorders, as items in indexed fields. The studies were obtained through a MEDLINE search from 1970 to 2012. We also examined additional studies cited in articles from these searches or our previous studies. RESULTS Several studies have shown poorer outcomes for patients with bipolar and comorbid anxiety disorders. Some studies have indicated worse outcomes in patients with bipolar disorder and associated anxiety disorders. Shorter periods of euthymia, increased suicidal thoughts and an increased number of suicide attempts were observed. Whether the effective treatment of anxiety reduces suicide and the severity of bipolar disorder or improves the response to treatment remains unknown. There are no well-designed intervention studies in bipolar patients with anxiety symptoms. CONCLUSION Further studies concerning the influence of anxiety on the course of bipolar disorder would be useful.