Adjunctive treatments needed for anxiety co-morbidity in bipolar disorder

Co-morbid anxiety is a clinically relevant factor in bipolar disorder and adjunctive treatments for such co-morbidity are greatly needed, say the authors of a recent study.Previous research has shown that depressed patients with co-morbid anxiety have more severe and chronic illness than those without. In addition, there is some evidence to suggest that co-morbid anxiety is also relevant in bipolar disorder.Researchers in the US conducted a study to evaluate whether co-morbid anxiety in bipolar illness is associated with increased severity, historical chronicity and a poorer response to pharmacological treatment (administered alone or in combination with family intervention). Another study goal was to evaluate the role of depression in the relationship between bipolar illness and co-morbid anxiety.Patients aged 18 to 75 years with diagnosis of bipolar I disorder (current episode manic, depressed or mixed) were recruited to the study. Severity of depressive and manic symptoms was assessed at baseline and then monthly for 28 months, using the Modified Hamilton Rating Scale for Depression (MHRSD) and the Bech-Rafaelsen Mania Scale (BRMS), respectively.Following baseline assessment, patients were randomised to one of three treatment groups: medication alone (n=29); medication plus family psychoeducational group (n=30); or medication plus family therapy (n=33).Patients with current or past history of anxiety disorder (28%) were included in the co-morbid anxiety group.The researchers observed higher levels of current depressive and manic symptoms in the co-morbid anxiety group than in the bipolar only group, even after controlling for current depression.Predictors of co-morbid anxiety identified in the study, included female sex and greater depression severity.Co-morbid anxiety was shown to have a detrimental effect on response to all treatment types, principally with respect to depressive symptoms. Further analyses showed that depression but not mania mediated the relationship between co-morbid anxiety and treatment outcome.The researchers recommend further research to examine whether variables other than depression (eg, psychotic severity) also mediate the relationship between co-morbid anxiety and severity.They add that although co-morbid anxiety is clearly associated with greater severity and poorer outcome in bipolar patients, further research is needed to establish the exact mechanisms of action. Reference...