Previous research into bipolar disorder and violent crime has found that those with the condition are more likely to engage in acts of violence. However, it is unclear whether the disorder itself, or some of the problems that go with it are behind the link. Researchers from the Karolinska Institutet in Sweden and Oxford University carried out research in Sweden where the state keeps a huge amount of information about people. They compared 3,700 patients with bipolar disorder, cared for in Swedish hospitals between 1973 and 2004, with 37,000 unaffected people from the general public. They found that the number of people committing violent crime was about the same in people with bipolar disorder and no substance-abuse problem and unaffected people (5% vs 3%). However, people with bipolar disorder and a substance-abuse problem were much more likely (21%) to commit violent crimes. The findings mirror similar research into schizophrenia which also found that it was schizophrenic's drug problems not their condition in itself that lead to an increased risk of violence.
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