Straight-A students have a much higher risk of
developing bipolar disorder than those who get average grades,
according to new
research.
The study, published in the February issue of
the British Journal of
Psychiatry, supports the belief that exceptional
intellectual ability is associated with bipolar disorder.
Historical studies and anecdotal reports of
famous and creative individuals suggest a link between high IQ and
bipolar disorder – but until now, the scientific evidence for such
a connection has been fairly weak. Researchers from the Institute
of Psychiatry, King’s College London, teamed up with researchers at
the Karolinska Institute in Sweden to investigate the association
further.
All children in Sweden take compulsory exams
at age 15-16, and the results are standardised nationally. The team
used the Swedish national school register to obtain the grades of
all students graduating from compulsory education between 1988 and
1997.
The researchers then used the Swedish hospital
discharge register to test associations between the students’
academic achievement and admission to hospital with a diagnosis of
bipolar disorder between the ages of 17 and 31. A total of 713,876
individuals were included in the study.
They found that students with excellent school
performance were almost four times as likely to develop bipolar
disorder as adults, compared to those with average grades. This
increased risk remained after the researchers controlled for other
factors such as parental education and socioeconomic status.
Students with the poorest grades were also at
a moderately increased risk of bipolar disorder. They were almost
twice as likely to develop bipolar compared to those with average
grades.
Lead researcher Dr James MacCabe, Senior
Lecturer at the Institute of Psychiatry, King’s College London,
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 researchers put forward several possible
explanations for the link. First, people in a state of hypomania (a
mild period of mania or elevated mood) can often be witty and
inventive, and able to link ideas in innovative ways. Second,
people with bipolar disorder often experience unusually strong
emotional responses, which may help their talent in art, music and
literature. Third, people with hypomania often have extraordinary
stamina and can keep concentrating for long periods of time.
These types of cognitive style may help
students perform better in creative school subjects – but also
predispose them to bipolar disorder in later life.
Equally, the opposite of this mechanism may
explain the link between poor school performance and bipolar
disorder. Some people who go on to develop bipolar disorder,
particularly those with depressive symptoms, may have cognitive
styles that impair their academic performance. It is also possible
that disturbed behaviour, substance misuse or undiagnosed
depression may affect their studies.
The research also showed that the association
between high grades and risk of later bipolar disorder appears to
be stronger in males than females. But this association was not
statistically significant and more research is needed to determine
if the link is truly stronger in males.
Dr MacCabe concluded: “Our study suggests that
getting A grades increases your chance of bipolar disorder –
although we should remember that the majority of people with A
grades enjoy good mental health.”
For further information, please contact Liz Fox or Deborah
Hart in the Communications Department.
Telephone: 020 7235 2351 Extensions. 6298 or 6127
References:
MacCabe JH, Lambe MP, Cnattinguis S, Sham PC, David AS, Reichenberg A, Murray RM and Hultman CM (2010) Excellent school performance at age 16 and risk of adult bipolar disorder: national cohort study, British Journal of Psychiatry, 196: 109-115