Brain-derived neurotrophic factor and suicidal behavior in patients with posttraumatic stress disorder

Abstract

Posttraumatic stress disorder (PTSD) is a severe illness affecting a substantial part of the population in both Western and developing countries. Many individuals suffering from PTSD display suicidal behavior. The association between PTSD and suicidal behavior has been observed both in clinical and in general population samples and is irrespective of the type of trauma that led to PTSD. The neurobiology of suicidal behavior in individuals of PTSD is not clear and is subject of research. Brain-derived neurotrophic factor (BDNF) may be involved in the neurobiology of suicidal behavior in PTSD because of its potential role in the pathophysiology of stress-related disorders. BDNF is one of mammalian neurotrophins which are homodimeric proteins. Multiple lines of evidence suggest that BDNF function is dysregulated in PTSD. Postmortem brain studies in suicidal subjects with or without depression, studies of levels of BDNF in blood cells/plasma of suicidal patients, and genetic association studies linking BDNF to suicide suggest that suicidal behavior may be associated with a decrease in BDNF functioning. It is not clear whether abnormal BDNF function is a marker of PTSD itself, or a marker of a neural vulnerability to PTSD. It is reasonable to hypothesize that reduced BDNF function increases vulnerability to PTSD and traumatic stress further decreases BDNF function. If BDNF dysregulation contributes to the pathophysiology of PTSD and suicidal behavior, it may underlie both conditions. If BDNF dysregulation is mostly a result of traumatic stress, it is logical to suggest that BDNF abnormalities mediate the effect of PTSD on suicidal behavior. Future studies of the role of BDNF function in the neurobiology of PTSD and suicidal behavior may lead to the development of new treatment modalities. It is interesting to hypothesize that treatment-induced enhancements of BDNF can facilitate neural integrity and recovery of function in PTSD, and consequently prevent suicidal behavior. This may be an important step in the direction of preventing suicide in individuals with PTSD. (PsycINFO Database Record (c) 2016 APA, all rights reserved)