Characterizing suicide in Toronto: an observational study and cluster analysis.
OBJECTIVE
To determine whether people who have died from suicide in a large epidemiologic sample form clusters based on demographic, clinical, and psychosocial factors.


METHODS
We conducted a coroner's chart review for 2886 people who died in Toronto, Ontario, from 1998 to 2010, and whose death was ruled as suicide by the Office of the Chief Coroner of Ontario. A cluster analysis using known suicide risk factors was performed to determine whether suicide deaths separate into distinct groups. Clusters were compared according to person- and suicide-specific factors.


RESULTS
Five clusters emerged. Cluster 1 had the highest proportion of females and nonviolent methods, and all had depression and a past suicide attempt. Cluster 2 had the highest proportion of people with a recent stressor and violent suicide methods, and all were married. Cluster 3 had mostly males between the ages of 20 and 64, and all had either experienced recent stressors, suffered from mental illness, or had a history of substance abuse. Cluster 4 had the youngest people and the highest proportion of deaths by jumping from height, few were married, and nearly one-half had bipolar disorder or schizophrenia. Cluster 5 had all unmarried people with no prior suicide attempts, and were the least likely to have an identified mental illness and most likely to leave a suicide note.


CONCLUSIONS
People who die from suicide assort into different patterns of demographic, clinical, and death-specific characteristics. Identifying and studying subgroups of suicides may advance our understanding of the heterogeneous nature of suicide and help to inform development of more targeted suicide prevention strategies.
Psychiatrist, Department of Psychiatry, Sunnybrook Health Sciences Centre, Toronto, Ontario; Assistant Professor, Department of Psychiatry, University of Toronto, Toronto, Ontario.
Mark
M
Sinyor
Head, Mood and Anxiety Disorders Program, Department of Psychiatry, Sunnybrook Health Sciences Centre, Toronto, Ontario; Associate Professor, Department of Psychiatry, University of Toronto, Toronto, Ontario.
Ayal
A
Schaffer
Professor, Department of Psychiatry, University of Toronto, Toronto, Ontario; Professor, Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario.
David L
DL
Streiner
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D016000:Cluster Analysis; D003644:Death Certificates; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D013405:Suicide / Q000145:classification / Q000523:psychology / Q000706:statistics & numerical data*; D055815:Young Adult
Toronto; cluster analysis; coroner records; suicide