title: Risk of Suicide Following Deliberate Self-poisoning.
abstract: OBJECTIVE
  Suicide is the tenth leading cause of death in the United States, and its rate has risen by 16% in the past decade. Deliberate self-poisoning is the leading method of attempted suicide. Unlike more violent methods, which are almost universally fatal, survival following self-poisoning is common, providing an opportunity for secondary prevention. However, the long-term risk of suicide following a first episode of self-poisoning is unknown.
  
  
  OBJECTIVE
  To determine the risk of suicide and mortality from other causes following a first self-poisoning episode.
  
  
  METHODS
  Population-based cohort study using multiple linked health care databases. We identified all individuals with a first self-poisoning episode in Ontario, Canada, from April 1, 2002, through December 31, 2010, and followed up all surviving participants until December 31, 2011, or death, whichever occurred first. For each individual with a deliberate self-poisoning episode, we randomly selected 1 control from the same population with no such history, matched for age (within 3 months), sex, and calendar year.
  
  
  METHODS
  The primary analysis examined the risk of suicide following discharge after self-poisoning. The secondary analyses explored factors associated with suicide and examined the risk of death caused by accidents or any other cause.
  
  
  RESULTS
  We identified 65 784 patients (18 482 [28.1%] younger than 20 years) who were discharged after a first self-poisoning episode. During a median follow-up of 5.3 years (interquartile range, 3.1-7.6 years), 4176 died, including 976 (23.4%) by suicide. The risk of suicide following self-poisoning was markedly increased relative to controls (hazard ratio, 41.96; 95% CI, 27.75-63.44), corresponding to a suicide rate of 278 vs 7 per 100 000 person-years, respectively. The median time from hospital discharge to completed suicide was 585 days (interquartile range, 147-1301 days). Older age, male sex, multiple intervening self-poisoning episodes, higher socioeconomic status, depression, and recent psychiatric care were strongly associated with suicide. Patients with a self-poisoning episode were also more likely to die because of accidents (hazard ratio, 10.45; 95% CI, 8.10-13.47) and all causes combined (hazard ratio, 5.55; 95% CI, 5.12-6.02).
  
  
  CONCLUSIONS
  A first self-poisoning episode is a strong predictor of subsequent suicide and premature death. Most suicides occur long after the index poisoning, emphasizing the importance of longitudinal, sustained secondary prevention initiatives.
authors.affiliation: Division of Emergency Medicine, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada2Division of Clinical Pharmacology and Toxicology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada3Child Health.
authors.forename: Yaron
authors.initials: Y
authors.lastname: Finkelstein
authors.affiliation: Department of Chronic Diseases and Pharmacotherapy, The Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.
authors.forename: Erin M
authors.initials: EM
authors.lastname: Macdonald
authors.affiliation: Department of Chronic Diseases and Pharmacotherapy, The Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada.
authors.forename: Simon
authors.initials: S
authors.lastname: Hollands
authors.affiliation: Department of Emergency Medicine, Queen's University, Kingston, Ontario, Canada7Department of Biomedical and Molecular Sciences, Queen's University, Kingston, Ontario, Canada.
authors.forename: Marco L A
authors.initials: ML
authors.lastname: Sivilotti
authors.affiliation: Division of Clinical Pharmacology and Toxicology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Janine R
authors.initials: JR
authors.lastname: Hutson
authors.affiliation: Department of Chronic Diseases and Pharmacotherapy, The Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada8Applied Health Research Centre, Li Ka Shing Knowledge Institute, St Michael's Hospital, Toronto, Ontario, Canada9Dalla Lana School.
authors.forename: Muhammad M
authors.initials: MM
authors.lastname: Mamdani
authors.affiliation: Division of Clinical Pharmacology and Toxicology, The Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada3Child Health Evaluative Sciences, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada4Department of.
authors.forename: Gideon
authors.initials: G
authors.lastname: Koren
authors.affiliation: Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada5Department of Chronic Diseases and Pharmacotherapy, The Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada10Institute of Health Policy, Management, and Evaluation.
authors.forename: David N
authors.initials: DN
authors.lastname: Juurlink
mesh_terms: D000328:Adult; D000368:Aged; D002170:Canada / Q000453:epidemiology; D016022:Case-Control Studies; D002423:Cause of Death; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011041:Poisoning / Q000401:mortality*; D012307:Risk Factors; D013405:Suicide / Q000706:statistics & numerical data*; D055815:Young Adult