The lifetime risk of an unexpected and sudden death from a cardiovascular cause in the absence of pre-existing heart disease-;known as sudden cardiac death-;is more than 4 times higher for people with schizophrenia than it is for the general population, indicates Danish research published online in the journal Heart . The risk is still around twice as high for those with other types of mental ill health, such as depression, whatever their age, indicate the findings, which suggest that an 18 year old can expect to live around 10 fewer years than someone of the same age without mental health issues. The research to date indicates that young people with a psychiatric illness are at heightened risk of sudden cardiac death, but it's not clear if that risk extends across the lifespan or if particular mental health disorders are associated with greater risk.

To find out, the researchers systematically reviewed all deaths occurring in 18 to 90 year old Danish residents over the course of 2010, drawing on information from death certificates and post mortem reports. Mental health disorders within the previous 10 years were defined according to International Classification of Diseases criteria or by prescriptions for psychotropic drugs filled within the preceding year. During the course of 2010, 45,703 people between the ages of 18 and 90 died.

In all, 6002 of these deaths were classified as sudden cardiac deaths: 3683 in the general population and 2319 among those with a mental illness.