Orygen researchers identify new biomarker to predict long-term risk of developing psychosis

Orygen researchers identify new biomarker to predict long-term risk of developing psychosis

30 April 2018

Orygen researchers identify new biomarker to predict long-term risk of developing psychosis

A study undertaken by Orygen researchers has revealed that low blood levels of an antioxidant called glutathione can be used as an indicator for the worsening of symptoms in patients at risk for psychosis.

The study, led by Orygen’s Dr Suzie Lavoie and Professor Paul Amminger, is especially important as, at present, the identification of psychosis risk is solely based on family history and subjective clinical presentation.

The measurement of glutathione levels provides an objective biological measure that could be added to the current set of diagnostic criteria and may improve the identification of individuals who will actually go on and develop a psychotic illness.

Around three in every 100 people will experience psychotic symptoms in their lives. Those symptoms vary, but include detachment from reality, disorganised or confused thinking, hallucinations, delusional thinking and lack of motivation. Finding effective methods of identifying young people at risk of psychosis can ensure treatments are provided early, leading to more favourable outcomes.

Dr Lavoie, a senior researcher at Orygen, said the identification of this new biomarker for psychosis could help inform treatment. The research was published in the journal Translational Psychiatry.

“Glutathione protects brain cells against stress, and can be screened for using a simple blood test,” she said. “This biomarker could be used to help predict people’s transition into psychosis, which is important as at the moment there are some individuals deemed at elevated risk for psychosis based on their clinical presentation who will actually never progress to develop the illness.

“Pharmaceutical intervention may not be necessary in these people, and may in fact be damaging depending on the invasiveness of the treatment strategy.”

Dr Lavoie said objectively distinguishing false positives from true positives based on measurable levels of glutathione could avoid those individuals who would have never developed psychosis having unnecessary exposure to medications.

“The identification of a biomarker for predicting transition to psychosis in ultra-high risk individuals is instrumental for targeting and improving the effectiveness of early detection and intervention,” she said.

Previous studies using a nutraceutical supplement, called N-acetylcysteine (NAC), for improving symptoms when added to conventional antipsychotic medication have shown encouraging results. It is believed that NAC may increase brain glutathione levels.

The ENACT trial at Orygen will investigate whether changes in brain glutathione levels following treatment with NAC in first episode psychosis patients may have a positive impact on symptoms, neurocognition and brain functioning.