Increasing rates of premature death and violence in people with schizophrenia
New research from Karolinska Institutet and Oxford University shows that rates of premature death and violent crime in people with schizophrenia are increasing, compared to the general population. The study, published in The Lancet Psychiatry journal, analyses long-term adverse outcomes between 1972 and 2009 in nearly 25,000 people in Sweden diagnosed with schizophrenia or related disorders.
For the first time, the researchers compared adverse outcomes – including conviction for a violent crime, premature death (before the age of 56), and death by suicide – in people with a diagnosis of schizophrenia to both the general population and to unaffected siblings. This allowed the research team to account for risk factors within families, such as parental criminality or violence, which might be expected to affect the risk of suicide or violent behaviour in siblings.
The results show that within five years of diagnosis, around one in 10 (10.7%) of men and around one in 37 (2.7%) of women with schizophrenia were convicted of a violent offence; around 1 in 50 men and women with schizophrenia (2.3% of men and 1.7% of women) died by suicide within five years of diagnosis. Overall, men and women with schizophrenia were eight times more likely to die prematurely than the general population. Although the prevalence of violent crime in people with schizophrenia was higher than that of death by suicide, statistical analysis showed that the link between schizophrenia and suicide is substantially stronger than that between schizophrenia and violence.
Decreasing levels of inpatient care
Analysing the changing rate of adverse outcomes across the study period (1972 – 2009), the researchers found that the risk of premature death, suicide, and conviction for a violent offence has increased for men and women with schizophrenia in the last 38 years, compared with both the general population, and their unaffected siblings. The analysis also shows that these increased rates of adverse outcomes appear to be associated with decreasing levels of inpatient care for these patients.
“When reporting about the very intricate links between schizophrenia and these adverse outcomes, we should remember that most people with schizophrenia and related disorders are neither violent nor suicidal. It is important that these findings are not used to further stigmatize an already burdened group of patients”, says Professor Paul Lichtenstein at Karolinska Institutet’s Department of Medical Epidemiology and Biostatistics, who led the study.
The research was funded by the Wellcome Trust, and the Swedish Research Council.
Violent crime, suicide, and premature mortality in patients with schizophrenia and related disorders: a 38-year total population study in Sweden
Seena Fazel, Achim Wolf, Camilla Palm, Paul Lichtenstein
The Lancet Psychiatry, online 4 June 2014, doi:10.1016/S2215-0366(14)70223-8