I want to discuss what I’ve learned, and share some of my thoughts on what a mental health diagnosis is and what value it provides.

Diagnosis: The nature of a disease; the identification of an illness. -medicinenet.com

When I began to pen my thoughts for this post, my original intent was to begin the conversation on Posttraumatic Stress Disorder (PTSD) as I’d promised a couple of weeks ago. To get my definitions straight I went to what is often referred to as the “bible of psychiatry”: The Diagnostic and Statistical Manual of Mental Disorders. Specifically I went to the most recent version, the fifth edition, DSM-5. This is the standard reference manual for categorizing and diagnosing mental health disorders.

PTSD was first introduced in the third edition of the manual in 1980. The criteria for its diagnosis have evolved quite dramatically since that time. This isn’t terribly surprising as we should expect our understanding of the condition to have grown and in turn the ability to identify and characterize its symptoms. In fact, in the DSM-5, a new diagnostic category, “Trauma and Stressor Related Disorders” was created, and PTSD found its place there. It had previously been categorized as an “Anxiety Disorder”. The rationale for this move, as I understand it, is that PTSD also includes disruptions of other emotional states outside of the fear/anxiety spectrum. As I said it doesn’t surprise me that the diagnostic criteria have changed, but the fact that an entirely new category was created to accommodate the disorder is curious to me.

Even more peculiar to me is that the first diagnostic criterion in the DSM-5 is not a characteristic of the disorder. It is the identification of an external event that could have caused the disorder; “Exposure to actual threatened death, serious injury or sexual violence…”. I believe PTSD may be unique in the manual in this regard, i.e., the identification of a presumptive cause is a requirement for the diagnosis.

Approximately 15% of veterans of recent wars, that is those who served in the Vietnam War, the Gulf War, Iraqi Freedom or Enduring Freedom, suffer or have suffered from Posttraumatic Stress Disorder (PTSD). This observation has brought a lot of attention to the realness of this disorder. It would be easy to take this information and assume that PTSD is uniquely a combat veteran’s issue. The truth is though, an estimated 8% of Americans will suffer from PTSD at some point in their lifetime.

It was in the 1970s when the diagnosis PTSD first gained acceptance. It was the observation that a great many veterans returning from Vietnam were suffering from a condition connected to their combat experiences that demanded that a diagnosis be recognized. It was in 1980 that the condition was included in the Diagnostic and Statistical Manual for Mental Disorders. There’s been a huge amount of observational research on the effects of psychological trauma since that time. That research has certainly shed considerable light on the common behavioral symptoms and prevalence of the disorder, but the specifics of what external factors and personal characteristics result in the disorder, and how it manifests in different individuals remain elusive. The current diagnostic criteria are summarized as follows: 1) Exposure to a life-threatening event, serious injury or sexual violence. 2) Recurring memories or flashbacks. 3) Avoidance of trauma reminders. 4) Changes in mood or cognition. 5) Attention problems, easily startled or violent outbursts.

Most people don’t develop PTSD following a life-threatening or otherwise violent traumatic event. For the general population, the statistical probability of developing PTSD following trauma exposure is consistent with those figures above related to combat exposure, somewhere between 10-20%. That is a wide range, and its uncertainty reflects our limited understanding of the condition, but it clearly illustrates that PTSD is not the normative response.

So who are those, let’s just say 15%, and what makes them susceptible? How much, if any, does one’s genetic makeup influence their susceptibility? What roles do environment and experience play? Of course, these are standard questions we want to answer in order to understand any non-normative behavior, be it a disorder or an extraordinary capability such as elite athleticism or intellectual or artistic genius. In any case, the answers lie in the physiological mechanisms that drive all the behaviors that define our individuality.

It was the afternoon of February 12, 2010, at the University of Alabama in Huntsville. There was a biology department staff meeting in progress when professor Amy Bishop stood up from the meeting table, pulled out a gun, and began to shoot her colleagues. She shot six people, three fatally, before the gun malfunctioned and she was forced out of the room. I remember the day very clearly. Most of the people at that meeting were friends of mine. I had worked in some capacity in the past with everyone in that room including Amy Bishop.

The lives of each of the survivors of that horrific experience were drastically changed, their life views, their very constitutions, were forever reshaped. This may seem to be a statement of the obvious, as we can all imagine that witnessing such violence and loss of life, particularly of those close to us, would necessarily cause psychological distress that could persist and change how we think and feel. But in truth, the toll that this kind of experience can take on an individual is beyond the imagination, because how it manifests is unpredictable, extremely complex, and very particular to the individual.

One of the survivors of the UAH shooting, biology professor Dr. Joe Ng, made this very observation, that is that each of the survivors responded and coped differently with the trauma of that experience. He recognized and acknowledged that he, like everyone involved, had been undeniably changed by this event, and those changes weren’t simply explainable by psychological factors alone. It made him ask the question “…why are certain people resilient to PTSD while some are very sensitive?” As he looked into the scientific literature he discovered a growing body of research documenting incidences of physical manifestations of disease associated with Post Traumatic Stress. Many of these reports described symptoms that could be associated with immunological factors. To explore this connection, Dr. Ng collaborated with psychologist Dr. Eric Seemann to look for blood-based indicators associated with PTSD. The results of the pilot study provided compelling evidence that there is indeed a connection between the symptoms of Posttraumatic Stress Disorder and our immune system.