Behavioural Activation Therapy for Bipolar Disorder

Mood disorders including bipolar disorder and depression are common disabling disorders with depression affecting 11.2 to 16.0% of the general population and the lifetime prevalence of bipolar disorders at an estimated 4.4%. Although treatment with antidepressants medications is common and effective in some patients, 42.7% of patients show inadequate response to treatment with antidepressants and a large proportion (55.3%) continue to have ongoing depressive symptoms. Psychological and behavioural interventions such as cognitive behavioural therapy (CBT) and behavioural activation (BA) are effective treatment for depression alone or in combination with antidepressants. Depression can also occur in the context of bipolar disorder which is characterized by recurrent episodes of depression and mania (DSM-5). The depressive episodes within bipolar disorder may be similar to depressive disorder, however the management of these episodes is fraught with the challenge that antidepressant pharmacotherapy may precipitate manic episodes and lead to further destabilization of bipolar disorder. Therefore, an alternative to antidepressants and additional therapies are needed to support patients' recovery and mood stability, as well as to achieve better treatment response and remission. BA is not currently available in a structured format and has not been tested for its effectiveness in bipolar disorders in a specialized hospital-based program. The evidence for BA has been investigated in depression however the evidence for bipolar disorder is lacking, therefore this study aims to assess the effectiveness of BA as treatment for bipolar disorder.

This study is a pragmatic randomized controlled trial to test the effectiveness of behavioural activation in bipolar disorder. The pragmatic randomized controlled trial study design is a parallel 1:1 allocation comparing behavioural activation plus treatment as usual to waitlist control group plus treatment as usual. For this study the investigators will adopt the following principals simulating naturalistic real life clinical setting to test the study question based on the pragmatic design:

No restrictive inclusion criteria will be used. Adults with bipolar disorder will be asked to participate in this study Clinicians will deliver the BA program to participants randomized to receive the intervention The intervention will be an add-on to treatment as usual The comparison group will receive treatment as usual that may include medications, CBT and other therapies as required and decided by their clinical care The primary outcome is clinically relevant (improvement in depressive and manic symptoms)

Both the intervention and control groups will be assessed as intention to treat analysis with no measures to improve adherence to the study intervention or the comparator.

Patients with a diagnosis of bipolar disorders attending the mood disorders clinic, referred for assessment of bipolar disorder at the clinic or referred from community or other hospital services to the mood disorders clinic will be approached for participation in the study. In addition, family practices in the community will be informed of the study and asked to refer directly to the trial. Following initial screening for eligibility, potential participants will be asked to provide written informed consent prior to any study related procedures.

The investigators will employ a parallel group design to evaluate the effects of behavioural activation intervention to improve bipolar disorder-related outcomes. Eligible and consenting patients will be randomly allocated to the intervention or control arms using a 1:1 allocation ratio. Allocations will be generated using the computerized system. The randomization will use a block randomization system of block sizes of 2, 4 and 6. Allocation will be conducted by a research personnel who is not a clinician and will not know the participant clinical status to maintain allocation concealment.

This trial is an open label trial as blinding is not possible for participants (behavioural activation intervention) or the clinician administering the intervention.

Eligibility Criteria:
Inclusion Criteria:

* Clinical diagnosis of Bipolar Disorder
* Must be able to provide written informed consent
* Must be able to attend program sessions

Exclusion Criteria:

* Inability to understand written and spoken English
* Primary diagnosis other Bipolar Disorder.