Understanding the causes and triggers of bipolar disorder

Bipolar disorder, also known as manic depression, refers to severe episodes of mood disturbance ranging from depression to elation that affect a person's ability to function normally.

It is thought to affect one in every 100 adults at some time during their life and men and women appear to be affected equally. One in six people with the illness are thought to die by suicide. It is now well established that bipolar disorder runs in families and that genes play a role in influencing an individual's susceptibility to the illness. This hereditary factor has been portrayed in the TV show EastEnders: in a 2009 episode, the character Stacey Slater was diagnosed with the condition; Stacey's mother was known to be affected by the condition.

As part of the Wellcome Trust Case Control Consortium - a major study looking at the genetics of common, complex diseases - researchers at Cardiff University, led by Professor Nick Craddock, are trying to identify the many genes involved in bipolar disorder.

"Improving the lives of those with bipolar disorder requires an understanding of the causes and triggers of illness," says Professor Craddock. "Research is vital. It is fantastic that we have already seen 3,000 people but we urgently need more volunteers to get to the 6,000 people we know are needed to understand this complex, serious and often fatal illness."

The Wellcome Trust study aims to recruit volunteers who suffer from the condition to describe their experiences of illness and donate a DNA sample for analysis. They have already had help from Stephen Fry and Kerry Katona, both of whom have talked openly in recent years about their struggle with the condition.

Speaking about his involvement in the study, Stephen Fry has said: "If you took time to participate in this study, you've no idea how much good you will be doing. It would be a wonderful, a kind, a graceful and a noble thing to do. So much good for so little effort. How you will glow. By choosing to assist one of the greatest problems facing human happiness you will have done your bit to help remove stigma, shame and hidden pain as well as hastening the day when we all understand the operations of mind and brain a little better."

Professor Craddock and colleagues have now reached a major milestone in their recruitment: the half-way mark. The three thousandth volunteer is Kate Wilkinson, who was diagnosed four years ago, after completing her degree at the University of Oxford. She had been treated for anorexia and depression before being diagnosed as having bipolar disorder. Although she now takes lithium to manage her condition - which she refers to as "fire-fighting" - her life is still severely affected by the condition.

"Bipolar disorder has had a devastating effect on my life, triggering potentially life-threatening episodes of anorexia, mania and depression," says Kate. "Being diagnosed with bipolar has meant taking various medications to manage my condition but there is no magic pill and it is largely a case of trial and error. I cannot express strongly enough how important it is for anyone who has ever been affected by the condition to help with this research. With your support, we can enable Professor Craddock and colleagues to move closer to understanding what causes and triggers bipolar disorder and to help find better treatments in the future."

Professor Craddock would like to hear from individuals who have experienced one or more episodes of high mood (called mania or hypomania) at any time during their life. Volunteers will be visited at home by a researcher who will ask about their experiences and symptoms as well as taking a small blood sample. Any information give would be in strict confidence.

"Bipolar disorder, as with all mood spectrum disorders, can be a very distressing condition, but very little is known about the biology underlying it," says Sir Mark Walport, Director of the Wellcome Trust. "We know that there are likely to be many dozens of genes implicated which increase the risk of developing the condition. By taking part, volunteers will contribute to an improved understanding of the condition and, in time, potential new treatments."

For further information, including details of how to take part, visit the Bipolar Disorder Research Network.