Risk of Suicide Following Deliberate Self-poisoning

Abstract

; for the Canadian Drug Safety and Effectiveness Research Network (CDSERN) IMPORTANCE 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. DESIGN, SETTING, AND PARTICIPANTS 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. MAIN OUTCOMES AND MEASURES 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 AND RELEVANCE 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.

Risk of suicide after a concussion

“…Our findings are congruent with the results of past studies indicating that suicide attempts are the single most important long-term predictor of subsequent risk of suicide. 72,73 Additional long-term predictors confirmed in this analysis included male sex, low socioeconomic status and prior psychiatric history. 74,75 Past studies have cautioned that individual risk factors have low accuracy for predicting individual events.…”

Suicide Attempt as a Risk Factor for Completed Suicide: Even More Lethal Than We Knew

“…Nearly all have focused on cohorts assembled from convenience samples, thus failing to accurately characterize the risk for the general population, let alone the subset with psychiatric illness. Examples of these restrictions of convenience include cohorts comprised solely of patients admitted to the hospital after attempts (4–6), patients who have used a particular method of attempt (e.g., self‐poisoning) (5, 7, 8), or patients initially seen in emergency departments (9–14). …”

Risk of re-attempts and suicide death after a suicide attempt: A survival analysis

“…A history of previous suicide attempt is the strongest predictor for future suicidal ideation and behaviour (SIB), including suicide ideation, suicide attempts, and suicide [2–5]. For instance, in a 5 years follow-up of 302 individuals admitted to an inpatient psychiatric unit for medically serious suicide attempts, 37% of them made at least one further suicide attempt, and 6.7% eventually died by suicide [6].…”