'Does Ketamine Have Rapid Anti-Suicidal Ideation Effects?'

Suicide is defined as an act of violence toward oneself with the intention to die. Suicide completion is a prominent cause of worldwide mortality and its prevention poses a major challenge to the psychiatric and world health communities. The Centers for Disease Control and Prevention (CDC) reported that as of 2013, suicide was the 10th major cause of death – totaling 41,149 deaths in the United States (US) (Centers for Disease Control and Prevention, CDC)[1]. Despite a growing armamentarium of the psychiatric medications to treat mood disorders, effective pharmacologic interventions for suicidality continue to elude us. Statistics demonstrate no meaningful decrease in the rate of suicide [2, 3]. In fact, within the US, there has been an alarming 28.4% increase in the age-adjusted suicide rates (from 13.7 to 17.6 per 100, 000) for adults aged 35–64 years between 1999 and 2010 (CDC [4]), as well as a 2.4% increase in the age-adjusted death rate due to suicide in 2012 compared to 2011[5]. Suicide is a multi-factorial phenomenon and our current nosology addresses it within symptom components of other psychiatric conditions exclusively. Almost 90% of suicide cases are associated with some form of psychiatric illness, chiefly Major Depressive Disorder (MDD), Psychotic Disorders, or Borderline Personality Disorder [2]. The new DSM-5 Task Force and work groups recognized an emerging need for the investigation of suicidality as an independent phenomenon. To stimulate thinking along these lines, a new category “suicidal behavior disorder” was added to the manual under “Conditions for Further Study”[6]. Recent guidelines from the National Alliance for Suicide Prevention Research Task Force outline priority questions to guide current and future research on suicide. Paramount among this research agenda is defining the etiology of suicide with the aim of increasing detection and accurately predicting suicide risk to provide effective preventive services and interventions. In this review, we will describe current treatment approaches to suicidality and summarize the existing literature on ketamine as a potential treatment candidate. We will consider clinical trial data concerning the rapid antidepressant effects of ketamine in mood disorders, as well as the strength of evidence for ketamine’s anti-suicidal effect beyond its antidepressant actions. The neurobiology of suicide, including the role of glutamate, will be discussed.