The investigators have gone on to validate this approach in more than 108,000 subjects in 21 countries participating in the World Health Organization mental health project (J. Clin. Psychiatry 2010;71:1617-28).
Simple addition of suicidality risk factors, while a big step forward in risk assessment, is still a relatively crude predictive tool. More recently, Dr. Kessler, collaborating with Dr. Nock and others, has developed a much more sophisticated actuarial risk algorithm and applied it to more than 54,000 U.S. Army soldiers hospitalized for psychiatric disorders. They found that subjects who scored in the top 5% in terms of predicted suicide risk accounted for 53% of all suicides that occurred within the next 12 months. The suicide rate in this highest-risk group was massive: 3,624 per 100,000 per year as compared to a background rate of 18.5/100,000/year in the Army overall.
Moreover, nearly one-half of soldiers with a risk score in the top 5% had a 12-month composite adverse outcome, defined as another suicide attempt, death by suicide, accidental death, or psychiatric rehospitalization (JAMA Psychiatry 2015;72:49-57).
The need for data on imminent risk: Dr. Nock called this the biggest unmet need in suicidology; it’s what clinicians and family members desperately want but don’t have. At present there is “approximately zero data” on how to predict suicidal behavior in the hours, days, or weeks before it occurs, Dr. Nock said. Indeed, Dr. Franklin’s meta-analysis showed that in the past 50 years more than three-quarters of studies examining suicide risk have looked at risk a year or more in the future. Only 2% of studies have looked at risk during the window of the next month or so.
Numerous groups are now looking at real-time patient monitoring using cell phones and smart watches as a means of developing short-term risk predictors. These tools enable investigators to monitor changes in mood, thoughts, behavior, and physiology in large populations in order to see what leads up to a suicide attempt. Dr. Nock’s group is collaborating with information scientists at Massachusetts Intitute of Technology on such projects.
This technology also shows promise for therapeutic intervention. Dr. Franklin and coworkers have developed a brief, game-like mobile app to administer what he calls Therapeutic Evaluative Conditioning. In three soon-to-be-published randomized controlled trials, he has shown that this simple intervention – essentially, playing a game on a cell phone – resulted in reductions of 42%-49% in self-cutting and other nonsuicidal self-injury, 21%-64% reductions in suicidal planning, and 20%-57% decreases in suicidal behaviors, according to Dr. Nock.
Dr. Nock’s research is funded chiefly by the National Institute of Mental Health, the World Health Organization, and the Department of Defense; he reported having no financial conflicts. Dr. Klonsky’s research is largely supported by the American Foundation for Suicide Prevention.