Modern antidepressants may reduce risk of depressive relapse for patients with bipolar disorder

Dr Lakshmi Yatham, professor and head of the Department of Psychiatry at the University of British Columbia (UBC), stated: "Treating depression in bipolar disorder is challenging and the depressive episodes can be quite devastating for patients and their families."

"Reducing the risk of relapse is important because it can provide patients with a great deal of stability that ultimately lets them get back to the activities they enjoy and can greatly improve their quality of life," Dr Yatham continued.

This outlook of medical concern is arguably what inspired the recent study carried out by UBC researchers, led by Dr Yatham, respectively, into how effective modern antidepressants truly are when treating patients with bipolar disorder.

Patients with bipolar disorder will commonly experience intense changes in their emotional states, ranging from extreme highs and lows, thus resulting in strong feelings of depression.

During these depressive episodes, patients can also experience feelings of sadness and hopelessness, along with disinterest, or even a complete loss of pleasure and interest, in doing the things they used to enjoy.

A common type of therapy for bipolar patients is antidepressant adjunctive therapy, which is when antidepressants are prescribed with mood stabilisers and antipsychotic drugs.

However, the duration of this form of therapy has been widely debated, primarily due to a lack of evidence and genuine concerns that antidepressants may exacerbate the situation by inducing mania, and rapid changes in emotional states.

But now, in the world's first randomised clinical trial that assesses the effectiveness of antidepressant adjunctive therapy, the results suggest that extending the treatment period beyond current guidelines may actually help with preventing depressive relapses.

This trial involved a total of 178 patients with bipolar I disorder and was conducted at sites in Canada, India and South Korea.

The patients, all of whom were in remission from a depressive episode following treatment from modern antidepressants, were randomly assigned to either continue the same treatment for 52 weeks or switch to a placebo after eight weeks of treatment.

Over the course of a year, 46 per cent of patients from the placebo group were shown to have experienced a relapse of a mood event, when compared to only 31 per cent of the group who continued the treatment of antidepressants.

During an analysis of week six and onwards, researchers found that patients who continued antidepressant treatment were 40 per cent less likely to experience a relapse of a mood event, and 59 per cent less likely to experience a depressive episode.

It was ultimately found that there was no significant difference in the rate of manic episodes, nor the rate of adverse events between both groups.

As a result, the researchers discovered that patients with bipolar I disorder will experience depressive symptoms up to three times more frequently than manic symptoms.

Dr Yatham commented on these results, saying: "From the point where the two groups began receiving different treatments, we see a significant benefit for patients who continued treatment with antidepressants."

"Future revisions of bipolar guidelines will incorporate the evidence from this study and contribute to changes in clinical practice on how antidepressants will be used to manage patients with bipolar disorder," he concluded.