CANADIAN TASK FORCE ON PREVENTIVE HEALTH CARE
Please note: In 2003, the CTF updated its Grades of Recommendations to include an "I Recommendation" for situations where insufficient evidence exists to allow a recommendation to be made. (Formerly, these situations were captured under a "C Recommendation".) This change is not retroactive, and all "C Recommendations" made prior to 2003 have not been reevaluated in light of the new "I" recommendation grade. For a discussion of these recommendation grades, please link to the 2003 article in the Canadian Medical Association Journal here.
Prevention of Suicide
Prepared by Jane E. McNamee, MA, Research Associate, Department of Psychiatry, Chedoke McMaster Hospitals and David R. Offord, MD, FRCPC, Professor of Psychiatry, McMaster University, Hamilton, Ontario
To make recommendations regarding routine evaluation of suicide risk in individuals from high-risk groups, and interventions to prevent suicide in these individuals. This updates a 1990 report.
Burden of Suffering
Suicide has accounted for about 2% of annual deaths in Canada since the late 1970s. Eighty percent of all suicides reported in 1991 involved men. The male:female ratio for suicide risk was 3.8:1. In both males and females, the greatest increase between 1960 and 1991 occurred in the 15-to-19-year age group, with a four-and-a-half-fold increase for males, and a three-fold increase for females. The potential years of life lost (PYLL) to age 75 in 1986 due to suicide were 122,908 per 100,000 population, 97,613 among males and 25,295 among females in Canada.
Suicide rates in the Canadian Native population are more than twice the sex-specific rates, and three times the age- specific rates of non-Native Canadians (56.3 for Native males and 11.8 for Native females). Suicide rates in federal and provincial prisons vary from 8 to 47 times rates in the general population. People with family member who committed suicide are nine times more likely than others to kill themselves. The mentally ill (those with affective disorder, schizophrenia, neurosis, personality disorder or organic brain syndrome) and people with drug and alcohol problems are at greater risk (by a factor of 2.4 to 23 times) than the general population.
To evaluate or not to evaluate, on a routine basis, suicide risk in members of high-risk groups. Treatment options were medication; psychiatric consultation, referral or hospital admission; psychosocial or psychotherapeutic interventions (provision of social support, counselling); and environmental interventions (patient and family education, development and use of social support networks).
Rates of completed suicides and repeat suicide attempts, feelings of depression or suicidal urgency, number of suicidal thoughts and actions, psychological test results, student attitudes, and physician knowledge about and recognition of suicide risk.
MEDLINE was searched from January 1967 to November 1993 using the keywords "suicide", "attempted suicide", "parasuicide", "epidemiology", "at-risk populations", "prevention", "intervention", and "postvention". Study results were synthesized in table or graphic format only.
The 13-member Task Force of experts in family medicine, geriatric medicine, pediatrics, psychiatry and epidemiology used an evidence-based method for evaluating the effectiveness of preventive health care interventions. Recommendations were not based on cost-effectiveness of options. Patient preferences were not discussed.
Background papers providing critical appraisal of the evidence and tentative recommendations prepared by the chapter author were pre-circulated to the members. Evidence for this topic was presented and deliberated upon in 1- to 2-day meetings, 2 to 3 times per year from January 1993 to June 1993. Consensus was reached on final recommendations.
Benefits, Harms, and Costs
Effectiveness of routine evaluation of suicide risk in high-risk individuals by primary caregivers has not been evaluated. While experts suggest that individuals who commit suicide provide signals of their intentions, there is fair evidence that family practitioners are poor at recognizing psychiatric disorders and suicide risk. However, evidence from 2 pre-post studies suggests that physician education programs can increase knowledge and decrease suicide rates.
Curriculum or school-based programs which focus on increasing awareness, risk identification and community resources are not effective, and may, in fact, stimulate imitative suicidal behaviour. No studies evaluating Canadian curriculum-based programs were identified.
Community-based programs (suicide prevention centres, crisis centres and telephone hotlines) do not have a significant effect on suicide incidence, although they do attract high-risk individuals. The 97 Canadian suicide prevention and crisis centres have not been systematically evaluated due to non-comparability of data from different centres.
The effects of medical treatment were considered for patients with suicidal ideation and diagnosed depression. A 1971 cohort study reported fewer subsequent attempts among hospitalized attempters who received psychiatric counselling compared with those discharged before counselling. Data from a meta-analysis and a descriptive study suggest that certain antidepressant medications are effective in reducing suicidal behaviour and thoughts in persons with depression.
An RCT of parasuicides found no significant differences in psychological test results or subsequent attempts at 1 week follow-up between patients randomized to hospital admission and those discharged to home. This study lacked sufficient power to detect clinically significant differences between groups. A Canadian RCT randomized attempters to intensive follow-up or usual care and found a 2% decrease (not statistically significant) in subsequent attempts among the intensive group during the first 2 years.
Recommendation grade [A, B, C, D, E] and level of evidence [I, II-1, II-2, II-3, III] are indicated after each recommendation. Citations in support of individual recommendations are identified in the guideline text.
There is poor evidence to support inclusion or exclusion (from the PHE) of routine evaluation of suicide risk in individuals at high risk (those with a history of psychiatric illness, depression, substance abuse, particularly those living in isolation, those with chronic terminal illness, Native and Aboriginal young men, those with a family history of suicide and first generation immigrant women) [C, III]. However, evaluation is recommended for persons at high risk because of the high burden of suffering.
There is fair evidence for the benefit of physician education programs on
suicide prevention, and for reduction of suicide rate in
selected groups [B, II-3].
There is insufficient evidence to recommend referral to curriculum or school-based intervention/prevention and postvention programs [C, II-2, III] or to recommend for or against referral to community-based suicide prevention programs, crisis centres, and help lines [C, III].
There is fair evidence for medical treatment of suicidal
ideation [B, II-2, III], and good evidence for
treatment of diagnosed depression [A, I, III].
For patients with a history of suicide attempts, there is insufficient evidence for or against hospital admission or discharge to home [C, I], or intensive psychosocial follow-up with the Suicidal Risk Scale [C, I].
This report was externally peer-reviewed. Recommendations and background papers were sent for external peer review.
The 1989 U.S. Preventive Services Task Force recommended against routine evaluation of suicidal risk, but suggested that physicians be alert to signs of suicidal intention in patients at high risk.
The Canadian Task Force on Preventive Health Care developed this guideline with funding from Health Canada.
McNamee JE, Offord DR. Prevention of suicide. In: Canadian Task Force on the Periodic Health Examination. Canadian Guide to Clinical Preventive Health Care. Ottawa: Health Canada, 1994; 456-67.
Canadian Task Force on the Periodic Health Examination. The periodic health examination, 1990 update: 2. Early detection of depression and prevention of suicide. Can Med Assoc J. 1990; 142(11): 1233-8.
McNamee JE, Offord DR. Prevention of Suicide Can Med Assoc J. 1990; 142(11): 1223-30.