Diagnosed depression linked to violent crime, says Oxford University study

People diagnosed with depression are roughly three times more likely than the general population to commit violent crimes such as robbery, sexual offences and assault, according to psychiatric experts.

A study based on more than 47,000 people in Sweden, emphasised that the overwhelming majority of depressed people are neither violent nor criminal and should not be stigmatised.

“One important finding was that the vast majority of depressed people were not convicted of violent crimes, and that the rates ... are below those for schizophrenia and bipolar disorder, and considerably lower than for alcohol or drug abuse,” said Seena Fazel, who led the study at University of Oxford’s psychiatry department.

The researchers found that 3.7% of men and 0.5% of women committed a violent crime after being identified as clinically depressed. This compared with 1.2% of men and 0.2% of women in the general population.

The study tracked the medical records and conviction rates of 47,158 people diagnosed with depression over a period of about three years. It then compared th e data with the records of 898,454 people with no history of diagnosed depression.

Violent crime was defined as a conviction for any of the following: homicide or attempted homicide, aggravated or common assault, robbery, arson and sexual offences (including indecent exposure, and illegal threats or intimidation).

When the researchers took account of previous histories of violence, self-harm, psychosis and substance misuse, they still found a link between depression and violent crime. Marjorie Wallace, chief executive of the mental health charity Sane, said: “The majority of people with depression are never violent, yet people receiving a diagnosis can feel frustrated, angry and initially desperate.

“It is also very rare for anyone with depression to commit crime. This study does, however, show how important it is for professionals not to ignore those strong feelings and make clear people can come to terms with how they feel and recover.”

Depression is one of the most common forms of mental illness, affecting more than 350 million people worldwide. Treatment usually involves either medication or psychotherapy, or a combination of both.

Andrea Cipriani, a clinical researcher and consultant psychiatrist at Oxford who was not directly involved in the study, said the results show the importance of talking to depressed patients about how violent thoughts and behaviour can be part of their illness. “It’s relieving for patients to talk about what they feel,” he said. “It’s relieving to know there’s a way out and it’s treatable.”

Fazel noted that in guidelines for doctors treating major depression, there is considerable focus on whether a patient is likely to self-harm or attempt suicide, yet little attention is given to violence.

“Quite understandably, there is considerable concern about self-harm and suicide in depression. We demonstrate that the rates of violent crime are at least as high, but they don’t receive the same level of attention in clinical guidelines or mainstream clinical practice.” He added that the next step in the research would be to examine the links between depression and violence.