A Lifetime Prevalence of Comorbidity Between Bipolar Affective Disorder and Anxiety Disorders: A Meta-analysis of 52 Interview-based Studies of Psychiatric Population

BACKGROUND Bipolar affective disorder has a high rate of comorbidity with a multitude of psychiatric disorders and medical conditions. Among all the potential comorbidities, co-existing anxiety disorders stand out due to their high prevalence. AIMS To determine the lifetime prevalence of comorbid anxiety disorders in bipolar affective disorder under the care of psychiatric services through systematic review and meta-analysis. METHOD Random effects meta-analyses were used to calculate the lifetime prevalence of comorbid generalised anxiety disorder, panic disorder, social anxiety disorder, specific phobia, agoraphobia, obsessive compulsive disorder and posttraumatic stress disorder in bipolar affective disorder. RESULTS 52 studies were included in the meta-analysis. The rate of lifetime comorbidity was as follows: panic disorder 16.8% (95% CI 13.7-20.1), generalised anxiety disorder 14.4% (95% CI 10.8-18.3), social anxiety disorder13.3% (95% CI 10.1-16.9), post-traumatic stress disorder 10.8% (95% CI 7.3-14.9), specific phobia 10.8% (95% CI 8.2-13.7), obsessive compulsive disorder 10.7% (95% CI 8.7-13.0) and agoraphobia 7.8% (95% CI 5.2-11.0). The lifetime prevalence of any anxiety disorders in bipolar disorder was 42.7%. CONCLUSIONS Our results suggest a high rate of lifetime concurrent anxiety disorders in bipolar disorder. The diagnostic issues at the interface are particularly difficult because of the substantial symptom overlap. The treatment of co-existing conditions has clinically remained challenging.