|August 26, 2013|
Suicide occurs in all cultures and more than 1 million individuals die worldwide by suicide die annually. It is clearly a major public health issue. Forty to 80 percent of individuals who commit suicide are identified (retrospectively) as experiencing a major mental illness at the time of the suicide and 30-50% either had an active substance use disorder or die with a significant blood alcohol level at the time of their suicide.
In the current issue of the journal Molecular Psychiatry, Le-Niculescu and colleagues show that a combination of genetic markers and clinical symptoms retrospectively correlate with suicidal ideation, and that the genetic markers are present in individuals who died by suicide. There are many scales and predictive models for suicide but all fall afoul of the paradox that the symptoms are so prevalent in the population that their ability to prospectively predict who is suicidal is very low. The same may be true for the combined genetic/symptom model of Le-Niculescu and colleagues, but this new approach, combining biomarkers with other symptoms, certainly bears replication and further study.
Suicide is a good example of a behavior in which empirical data should inform the ethical considerations raised by the behavior. The issues discussed in the first paragraph above suggest that most suicides are not voluntary, that is, the result of a free choice by an informed individual. Furthermore, people who survive suicide often report that they are happy they survived. Multiple studies in recent years support the hypothesis that dying by suicide runs in families and has a genetic diathesis. Nonetheless, suicide rates vary by country and culture, age, sex and socioeconomic status, suggesting that societal and individual beliefs and values also influence who attempts suicide.
Many of the facts listed above support the conclusion that suicide prevention is ethically justifiable. Furthermore, the high prevalence of suicide supports makes it a high priority. The high prevalence also supports the view that a public health approach based on population-based screening is ethically justifiable. However, intervening sometimes requires transiently limiting a person’s freedom. Thus, an ethical analysis also requires that any suicide prevention program have in place legal safeguards which assure that each individual is assessed individually by an expert clinician and that an independent legal review confirms that the person’s choice has been significantly restricted by a clinical condition that has the characteristics of a freedom-impairing disease. At this time, however, no screening protocol, including that of Le-Niculescu and coworkers, meets established scientific criteria of very low false positive rates (negative predictive value) and good positive predictive value, but further work in this area remains imperative.
Peter Rabins, PhD, MPH, is a faculty member of the Johns Hopkins Berman Institute of Bioethics and director of the Division of Geriatric Psychiatry at the Johns Hopkins University School of Medicine.