Brightest more likely to suffer mental illness

Scientists found that pupils at the top of their class were four times more likely to develop bipolar disorder than children with average grades.

The condition is characterised by extreme mood swings alternating between depression and mania.

Previous research and anecdotal evidence from famous and creative individuals have suggested a link between high IQ and bipolar disorder. But until now, the evidence for such an association has been weak.

The new study looked at 713,876 individuals in Sweden, where all children take exams when they are 15 and 16.

Hospital records and school reports were studied to assess the chances of having bipolar disorder between 17 and 31.

Students with excellent exam results were almost four times more likely to be diagnosed with the condition than those whose performance was average.

Children with the poorest grades were also more at risk, the research showed. They were almost twice as likely to develop bipolar disorder as average achievers.

The findings are reported today in the British Journal of Psychiatry.

Lead researcher Dr James MacCabe said: "We found that achieving an A grade is associated with increased risk for bipolar disorder, particularly in humanities and to a lesser extent in science subjects.

"A-grades in Swedish and Music had particularly strong associations, supporting the literature which consistently finds associations between linguistic and musical creativity and bipolar disorder."

The scientists point out that people in elevated mood states can often be witty and inventive, and able to link ideas in innovative ways. They may also tend to be highly emotional, which may be an advantage in the arts. Thirdly, people who are mildly manic often have extraordinary stamina and can maintain concentration for long periods of time.