A blood test to determine a patient's suicide risk may be within reach.
Scientists at the University of New South Wales in Australia and colleagues in Sweden believe they've come up with a viable diagnostic biomarker: higher-than-normal levels of the neurotransmitter quinolinic acid. Through their work with an unnamed biotech, they expect to debut a working blood test for human clinical trials within the next year, the Australian Times reports. Ideally, such a test would process results with a day or two, enabling targeted personalized medicine-style treatments specific to reducing levels of quinolinic acid.
Why quinolinic acid? In small amounts, it's a good thing, researcher Gilles Guillemin explains to the Australian Times, enabling energy production and DNA repair. But higher-than-normal levels are essentially a neurotoxin, he told the news service.
In their previous research, the team found that individuals with high levels of the substance in their brain appeared severely depressed or suicidal, apparently because the higher-than-normal levels of quinolinic acid overly excite a patient's brain chemistry. So logic suggests that the substance could indicate suicide risk. They used a technique called a gas chromatography-mass spectrometry to quantify the levels of quinolinic acid in samples from suicidal patients.
Typically, researchers have zeroed in on the connections between the brain chemical serotonin and depression. Some see this new research as opening the door to a new avenue for both diagnosis and treatment of severely depressed or suicidal patients. But the Australian Associated Press notes that the test might be more viable as a research tool, one that could help researchers investigate how quinolinic acid may affect conditions beyond depression and suicidal states, including Alzheimer's disease and schizophrenia.