People with bipolar disorder are more than twice as likely to have suffered serious childhood adversity, such as physical or sexual abuse, a new study has found.

UK researchers assessed 19 studies published between 1980 and 2014, which contained data on millions of patient records, as well as interviews and assessments.

They found a strong link between bipolar disorder and childhood adversity.

Bipolar disorder, previously known as manic depression, results in a person experiencing periods of elation or mania, alternating with periods of deep depression.

The researchers noted that there is an urgent need to better understand the risk factors for this condition, as this would help improve detection and treatment.

For the purpose of the study, childhood adversity was defined as neglect, emotional, physical or sexual abuse, bullying or the loss of a parent before the age of 19.

The researchers found that those with bipolar were more than twice as likely (2.6 times) to have suffered emotional, physical or sexual abuse. In fact, there was a particularly strong link between emotional abuse and the condition, with those abused in this way more than four times more likely to develop bipolar.

However, the loss of a parent did not appear to increase the risk of bipolar significantly.

"Much research into bipolar has focused on bio-genetics, but following previous work on schizophrenia, we felt that a similar effect could be found in bipolar. The link between experiencing a troubled childhood and subsequently being diagnosed with this serious condition is extremely strong," commented one of the study's authors, Dr Filippo Varese, of the University of Manchester.

The researchers believe that these findings have implications for professionals working in this field, as they can factor in these childhood experiences when developing therapy plans for individuals.

"Handled sensitively, enquiries about a person's childhood experiences can make a significant difference to how treatment proceeds and the types of support that can be put into place," commented the study's lead author, Dr Jasper Palmier-Claus.

Details of these findings are published in the British Journal of Psychiatry.