A new Deakin University and Barwon Health study has found an old treatment for bipolar is much more effective than a newer medication.

The study tested the effects of lithium, a mood stabiliser introduced in the 1970s, compared with those of quetiapine, now a more commonly prescribed alternative, on patients who had had a manic episode for the first time.

Lead researcher Professor Michael Berk, Director of Deakin's Centre for Innovation in Mental and Physical Health and Clinical Treatment at Barwon Health, said lithium seemed to be better than quetiapine in protecting the brain after a first episode of illness.

Professor Berk said it was important to independently test the effectiveness of mental health medications, as sometimes their popularity was affected by factors outside of successful treatment.

"Mood stabilisers are the mainstay of treatment of bipolar disorder and are essentially used to keep people well," he said.

"The oldest drug we have is lithium, but there are some new contenders, principally medicines called atypical antipsychotics, which are usually used for schizophrenia, and quetiapine is one of the best examples.

"Lithium has a lot of side effects and the newer agents have gained traction such that they have become first-line and widely used treatments.

"Because of its side effects and because of marketing, lithium has gradually fallen out of favour, despite the fact that most guidelines recommend it as a first-line treatment."

The study was completed with the support of Orygen, The National Centre of Excellence in Youth Mental Health, The University of Melbourne, Southern Health, and Monash University.

Professor Berk said it evaluated people who had a first episode of mania, half were treated with lithium and the other half with quetiapine. Their symptoms and brain scans at the start of the trial, after three and then 12 months were compared.

"At the beginning of the study the patients with first episode mania showed reduced grey and white matter in some brain areas compared to the control group," Professor Berk said.

"Brain scans on first episode mania patients at three and 12 months showed that lithium was more effective than quetiapine at slowing the progression of white matter volume reduction.

"Grey and white matter are the two major compartments of brain tissue. Essentially grey matter are the cells and white matter are the fibre tracts that connect these cells.

"The volume of these brain areas is important because there is research that says that some people with psychiatric disorders can lose brain volume and hence, tissue. So, any drug that protects the brain has major theoretical and clinical benefits.

"This data therefore supports the continuing use of lithium from the earliest stages of disorder, ideally from the first manic episode, something that challenges some guidelines that propose lithium only for use after several episodes."

Professor Berk's paper 'Neuroprotection after a first episode of mania: a randomized controlled maintenance trial comparing the effects of lithium and quetiapine on grey and white matter volume' was published in Translational Psychiatry.

Article: Neuroprotection after a first episode of mania: a randomized controlled maintenance trial comparing the effects of lithium and quetiapine on grey and white matter volume, M Berk et al., Translational Psychiatry, doi:10.1038/tp.2016.281, published online 24 January 2017.