A SIMPLE IQ test developed by Scottish scientists will be able to predict whether people are likely to suffer schizophrenia up to three years in advance.

Researchers at Edinburgh University believe their test — which measures IQ, memory, motor skills and verbal learning — can be used to take action against the illness, which typically strikes people aged between 17 and 30, from being triggered.

Although schizophrenia cannot be cured, early treatment has been shown to improve recovery rates.

The study, published in the British Journal of Psychiatry, is part of the Edinburgh High-Risk Study led by Professor Eve Johnstone at the university’s department of psychiatry. Over a 10-year period the team examined 163 people, aged 16-24, with a family history of schizophrenia and did brain scans on them.

The results were compared with a group who had no family history of the illness. While 45% of the high-risk group showed symptoms of schizophrenia, only 12% went on to became sick. The differences were identified between two and three years before they fell ill.

“We can now very accurately identify those who do not have to worry, despite having a family history of schizophrenia,” said Johnstone.

“The people who went on to develop schizophrenia were very normal, charming, impressive people but we found that they had personality factors that were different. They were more anxious, inclined to be more shy and to be oversensitive. Their IQs were normal but their memories were not quite so good. One part of their brain, the thalamus, was smaller.

“What this shows is that these people inherit a vulnerability to the condition that may switch into schizophrenia. If we could hold them in this state of vulnerability it would be a wonderful thing.

It is estimated that up to 20,000 people in Scotland suffer from the disorder. The greatest risk they pose is to themselves, with about 5% committing suicide.

Ian Harper, of National Schizophrenia Fellowship (Scotland), said: “Even though it will initially benefit a small number of people who have a family history of schizophrenia, it is still a step forward. Getting treatment as early as possible is the best course of action as there is no cure for schizophrenia.”

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