Blood test can predict risk of suicide

LONDON — A blood test that can predict whether someone may attempt suicide has been developed by scientists in a breakthrough which could prevent hundreds of deaths.

American researchers have found that variations in a single gene can be used to predict if someone is likely to take their own life. Those mutations can be spotted through a simple blood test which could allow therapists or doctors to intervene before it is too late.

It could be useful for screening soldiers before they enter war zones, or checking their risk of suicide on their return, the scientists say.

Researchers at John Hopkins University, in Baltimore, Maryland, found that the gene SKA2 stopped functioning correctly in people at risk of suicide. The gene, found in the prefrontal cortex of the brain, is responsible for keeping levels of cortisol — the stress hormone — under control. It is also involved in preventing negative thoughts and controlling impulsive behaviour.

If there is insufficient SKA2, or it is altered in some way, the body cannot control levels of cortisol. Previous research has shown that people who attempt suicide or take their own lives have large amounts of cortisol in their systems.

“Suicide is a major preventable public health problem, but we have been stymied in our prevention efforts because we have no consistent way to predict those who are at increased risk of killing themselves,” said study leader Dr Zachary Kaminsky, an assistant professor of psychiatry and behavioural sciences.

“With a test like ours, we may be able to stem suicide rates by identifying those people and intervening early enough to head off a catastrophe.”

The blood test managed to predict those with the most severe risk of suicide with 90 per cent accuracy.

The scientists could also spot if someone had already attempted suicide with 96 per cent accuracy, simply by looking at the levels of SKA2.

A test could allow doctors or psychologists to place patients on “suicide watch” and restrict their access to drugs or equipment which they could use to end their own life. Dr Kaminsky said it could also help doctors know whether to give medications which are linked to suicidal thoughts.

“We have found a gene that we think could be really important for consistently identifying a range of behaviours from suicidal thoughts to attempts to completions,” Dr Kaminsky said. “We need to study this in a larger sample, but we believe that we might be able to monitor the blood to identify those at risk of suicide.”

The research was reported in the American Journal of Psychology.