Sudden death in patients with serious mental illness

Sudden death is used to define a death under suspicious circumstances, where there is no clear indication of existing medical illness (natural cause) that accounts for the death or clear indication for the cause of death. This includes all deaths from suicide, unintentional poisoning, drowning, falls and violence. Sudden death contributes to the increased mortality in people with serious mental illness (premature mortality) but is far less frequently studied and understood. This study analyses data of all sudden deaths of patients who had been under the care of the Canterbury District Health Board's Specialist Mental Health Service, New Zealand's second-largest population region. The study identifies key sociodemographic, diagnostic, legal and causative factors in the study population. This study aims to identify targeted interventions to mitigate premature mortality in this population.

Data was obtained from the clinical files and the coroner's findings for all sudden death patients with established contact with Specialist Mental Health Services in the Canterbury region of New Zealand, between 2005 and 2009.

A total of 313 patients were identified. The median age at the time of death was 42 years (IQ Range 32.5-53 years). Of these, 65% (n=203) were male. Seventy-six percent (n=239) were of European descent and 9% Māori (n=29); 68% (n=280) were under care at the time of their death and 15% (n=32) were under the Mental Health Act. The sudden death rate was 0.36% for those under voluntary care and 0.7% for those under compulsory care. The most common primary diagnoses were alcohol or other drug abuse (29%); depression (25%); psychotic disorders (18%); BPAD (9%) and personality disorder (5%). The most common cause of death was suicide (51.8%) followed by motor vehicle crashes and falls, (23.3%) medical causes (17.6%) and homicide (1.3%). Of those that died by suicide, 75% were male. Hanging was the most common method (48%) followed by carbon monoxide poisoning (9.3%); medication overdose (5.8%) and falls from a height (3.5%).

The most common cause of sudden death was suicide, which was overwhelmingly the leading cause of sudden death in patients discharged or lost to follow up. The most potent predisposing factor appeared to be drug and alcohol problems. Mental health services should therefore advocate for comprehensive and evidence-based alcohol and drug policies, including access and availability to treatment programmes.