Anxiety disorders and childhood maltreatment as predictors of outcome in bipolar disorder

Background
Comorbid anxiety disorders and childhood maltreatment have each been linked with unfavourable outcomes in people with bipolar disorder. Because childhood maltreatment is associated with anxiety disorders in this population, their respective predictive value remains to be determined.
Methods
In 174 adults with bipolar disorder, we assessed childhood maltreatment using the Childhood Trauma Questionnaire and lifetime anxiety disorders with the MINI International Neuropsychiatric Interview. We constructed an overall index of severity of bipolar disorder as a sum of six indicators (unemployment, psychotic symptoms, more than five manic episodes, more than five depressive episodes, suicide attempt, and hospital admission). We tested the relationship between childhood maltreatment, the number of anxiety disorders and the overall severity index using ordered logistic regression.
Results
The number of lifetime anxiety disorders was associated with the overall severity index (OR = 1.43, 95%CI = 1.01–2.04, p = 0.047). This relationship was only slightly attenuated when controlled for childhood maltreatment (OR = 1.39, 95%CI = 0.97–2.00, p = 0.069). The relationship between childhood maltreatment and the overall severity index was not statistically significant (OR = 1.26, 95%CI = 0.92–1.74, p = 0.151). Secondary analyses revealed that childhood maltreatment was associated with suicide attempts (OR = 1.70, 95%CI = 1.15–2.51, p = 0.008) and obsessive compulsive disorder was associated with the overall severity index (OR = 9.56, 95%CI = 2.20–41.47, p = 0.003).
Limitations
This was a cross-sectional study with a moderate-sized sample recruited from a specialist program.
Conclusions
While comorbid anxiety disorders are associated with the overall severity of bipolar disorder, childhood maltreatment is specifically associated with suicide attempts. Clinicians should systematically assess both factors. Interventions to improve outcomes of people with bipolar disorder with comorbid anxiety disorders and history of childhood maltreatment are needed.