Leo Sher, M.D.

Suicidal behavior among war veterans may frequently be related to depression and/or PTSD (1-5). The risk of suicide attempts among the PTSD population is six times greater than in the general population (2) and even higher among treatment seeking war veterans with PTSD (3). Several years ago, I proposed that some or all individuals diagnosed with comorbid PTSD and MDD have a separate psychobiological condition that can be termed “posttraumatic mood disorder” (PTMD) (4,5). This idea was based on the fact that a significant number of studies suggested that patients suffering from comorbid PTSD and MDD differed clinically and biologically from individuals with PTSD alone or MDD alone.Individuals with comorbid PTSD and MDD are characterized by greater severity of symptoms, increased suicidality and the higher level of impairment in social and occupational functioning compared to individuals with PTSD alone or MDD alone. Neurobiological evidence supporting the concept of PTMD includes the findings from neuroendocrine challenge, cerebrospinal fluid, neuroimaging, sleep and other studies.

I have recently proposed a model of suicidal behavior in war veterans with PTMD (6). The model consists of the following components: (1) genetic factors: converging evidence from multiple studies supports a role for genetic influences in the etiology of PTSD, depression and suicidal behavior; (2) prenatal development: antenatal factors may affect the psychological development of offspring; (3) biological and psychosocial influences from birth to mobilization/deployment: various biological and psychological factors may affect the sensitivity of a person to traumatic events and play a role in the development of PTSD, depression and suicidal behavior; (4) mobilization/pre-deployment stress; (5) combat stress, traumatic brain injury, and physical injury; (6) post-deployment stress, including interpersonal, family and occupational difficulties; (7) biological and psychosocial influences after the deployment such as perceived social support, stressful situations, ongoing threat to safety, the state of health, nutrition, alcohol and drug use; (8) triggers (precipitants) of a suicidal acts including interpersonal losses or conflicts, financial trouble, and job problems; and (9) suicidal act. The first four components determine predisposition to combat stress. The first seven components determine vulnerability to suicidal behavior, a key element that differentiates PTMD patients who are at high risk from those at lower risk. Suicidal behavior in PTMD can be attributed to the coincidence of a trigger with a predisposition for suicidal behavior.

References

1. Panagioti M, Gooding P, Tarrier N. Post-traumatic stress disorder and suicidal behavior: A narrative review. Clin Psychol Rev. 2009;29(6):471-482.
2. Kessler RC. Posttraumatic stress disorder: the burden to the individual and to society. J Clin Psychiatry. 2000;61 Suppl 5:4-12.
3. Zivin K, Kim HM, McCarthy JF, Austin KL, Hoggatt KJ, Walters H, Valenstein M. Suicide mortality among individuals receiving treatment for depression in the Veterans Affairs health system: associations with patient and treatment setting characteristics. Am J Public Health 2007;97(12):2193-2198.
4. Sher L. The concept of post-traumatic mood disorder. Med Hypotheses 2005;65(2):205-210.
5. Sher L. Posttraumatic mood disorder: a new concept. Can J Psychiatry 2005;50(2):127-128.
6. Sher L. A model of suicidal behavior in war veterans with posttraumatic mood disorder. Med Hypotheses 2009;73(2):215-219.