Sunday, March 28, 2010

PTSD and DSM: Science and Politics -- Again

With the ongoing war in Iraq, Post Traumatic Stress Disorder -- PTSD is much in the news nowadays.  We can expect that to continue.

Nancy Andreasen, author of The Broken Brain, traces the social history of this mental illness in a 2004 American Journal of Psychiatry article.  The features of what we call PTSD have long been noted in the annuls of warfare.  More recently, in World War I it was called shell shock, and those who had it were shot for cowardice in the face of the enemy.  In World War II it was recognized as a mental illness and called battle fatigue.  Afflicted soldiers were removed from the front and given counseling designed to return them to battle within the week -- though there is one infamous story about General Troglodyte Patton who, while touring a hospital, cursed and slapped one such soldier for his "cowardice."

The DSM I, from the post-WWII era, recognized battle fatigue as Gross Stress Disorder.  It was removed from the DSM II in the early 1960s , when U.S. society was not regularly confronted with this cost of war.

Andreasen had the task of addressing Gross Distress Disorder again in the 1980s for DSM III, when veterans' groups wanted its return as Post-Vietnam syndrome.  Given her experience with burn victims, Andreasen pressed for a more inclusive description of the illness.  Post Traumatic Stress Disorder entered the new edition, described as a stress reaction to a catastrophic stressor that is outside the range of usual human experience.

In both DSM III and IV, the first criterion for PTSD is not a symptom, but an event.  The DSM IV widened the application to include events that are not necessarily out of range of usual human experience:  The person experienced, witnessed, or was confronted with an event or events that involved actual or threatened death or serious injury, or a threat to the physical integrity of self or others. In addition, The person's response involved intense fear, helplessness, or horror.  This criterion has been applied to a wider assortment of events, the traumas of rape, child abuse, auto accidents, earthquakes and even witnessing events not experienced directly.  David Conroy argues that being suicidal fits the description, and that those who have been suicidal may exhibit the symptoms of PTSD, as well.  The literature on suicidality, depression and PTSD notes that these three sometimes co-concur, but I have found no one else who considers that the threat of death may come from ones own self.

The DSM V tightens the criteria, though some would say not enough.  The traumatizing event now is described this way: The person was exposed to the following event(s): death or threatened death, actual or threatened serious injury, or actual or threatened sexual violation.  It also identifies specific means of exposure to the event, and eliminates others.

Andreasen expresses a conservative approach, Giving the same diagnosis to death camp survivors and someone who has been in a motor vehicle accident diminishes the magnitude of the stressor and the significance of PTSD.  Sally Satel, also a psychiatrist and a Fellow at the American Enterprise Institute puts it more provocatively, "We've dumbed down PTSD."  There is a false assumption, she added, that ''if something bad happens, people are damaged unless they talk about it.''

Perhaps the confusion about what we now call PTSD arises from the focus on the traumatic event.  The world has long known that war messes with soldiers' minds.  Other traumas are more individual and not so easily observed by the general public.  So similarities are obscured.  Common sense says that a death camp and an auto accident are of a different magnitude of trauma.  However, the differences become less obvious when viewed from the perspective of symptoms.  Each edition of the DSM has struggled with the differences and similarities, and each lurched from one direction to another.

Focus on some precipitating event for PTSD runs counter to diagnostic criteria for other mental illnesses, where the symptoms are given priority.  In some illnesses, such as depression, it is widely accepted that experiences and environment play a role in causation.  Past attempts to diagnose depression by its source (reactive, meaning in response to an event, or endogenous, meaning arising from biological sources) have been abandoned as unhelpful, since biological processes are part of any depression.

People with similar circumstances do not necessarily develop the same illness.  And most people who experience even a significant trauma do not develop PTSD, or they have symptoms that are easily resolved.  So why do some experience intrusive memories, feel numb and avoid triggers for years after the original event?

As it happens, the same therapies, antidepressants, anti-anxiety medications and cognitive behavioral therapy are used to treat both depression and PTSD, suggesting that these illnesses may be similar in other ways.

In fact, the brain science supports the comparison.  Stress plays a significant role in both.  Neuroscientists are studying three biochemical changes in the brain that occur under severe stress and persevere past the stress.
  • The locus ceruleus (marked in pink to the right) becomes over-active and releases too much of hormones called catecholamines, used to respond to an emergency, even when there is no emergency.
  • Pathways that connect the hypothalamus, pituitary gland and amygdala (HPA axis) fail to regulate another hormone used in crisis, called corticotropin-releasing factor (CRF).  (The hippocampus is green in the graphic, the amygdala blue and the pituitary gland yellow. -- Yes, I did have fun with the airbrush in my paint program!)
  • The opioid system of the brain also becomes overactive, releasing more endorphins, which cause a higher tolerance for pain, accounting for the numbed feelings of PTSD, and which eventually become depleted, causing loss of interest, one of depression's core symptoms.
In addition, each of these systems feeds into the others.

These hormones are necessary to help the body deal with potential pain and danger.  Under smaller stress, feedback systems tell the brain to back off when the danger has passed.  However, an intense enough stressor changes these underlying brain functions.  It destroys the feedback systems and dis-regulates processes that otherwise right themselves and return the brain to a stable state when the stress has passed.

But what is intense enough?  It depends on the individual.  Those who perceive they have some control over the traumatic event are at less risk.  For example, a fire fighter has more resources and so more control than somebody else caught in a burning building.  The fire fighter would be at less risk for PTSD.

Adults who were abused, or who faced many extreme stresses in their early lives, are at greater risk for developing PTSD following later trauma than others who do not have the same history.  The brain science demonstrates that their brains have been primed, by damage to these critical areas of the brain.

Another finding reveals the original insight behind calling it shell shock.  Explosions send out waves of energy that can cause concussions, traumatic brain injuries or TBIs.  These physical injuries create the same neurological stresses as what are thought of as psychological stresses.  Even minor TBIs, in which there is only short or no loss of consciousness, set up the brain conditions for developing PTSD.  TBIs also result from blows to the head, as in an assault, flying debris or a motor vehicle accident.

These findings explain why individuals vary by the trauma threshold that can cause the brain changes and consequent symptoms, and why an event that most are able to shake off is devastating to a smaller portion of the population.  Just as "reactive depression" became an obsolete notion, perhaps it is time to stop defining the exact nature of the trauma behind PTSD and focus instead on the biology. 

In fact, a Walter Reed Army Institute study of 2,525 U.S. Army infantry soldiers discovered that minor TBIs are more likely to result in PTSD than severe TBIs with loss of consciousness for ten or more hours.  The theory is that PTSD comes from recording memories in a malfunctioning hippocampus.  Those who go in and out of consciousness, or remain conscious but are dazed, have more memories to be recorded, hence more memories to become intrusive at a later date.

At stake are billions of dollars, as diagnosis has increased exponentially, as the illness is asserted in personal injury lawsuits, as Viet Nam vets present themselves for treatment of "reactivated" PTSD, and as the war in Iraq produces more soldiers with more problems.

The scope of the problem from the Iraqi war is enormous.  From the Washington Post report of the Walter Reed study: Head and neck injuries have been reported in one quarter of troops evacuated from [Iraq and Afghanistan.]  The proportion of soldiers with concussion may be as high as 18 percent... Almost 44 percent of soldiers reporting an injury involving loss of consciousness met the criteria for PTSD versus only 27.3 percent of those reporting an injury involving altered mental status, 16.2 percent of those with other injuries and 9.1 percent of those with no injury.  A 2008 RAND Corporation study put the incidence of PTSD in soldiers who have served in Iraq at 13.8%.  Other studies claim much higher numbers.

Debate continues about how inclusive or restrictive the criteria for diagnosis should be, with the proposed DSM V drifting toward the more restrictive criteria, where the economics of PTSD converge with the politics.  Repeating Andreasen from above, Giving the same diagnosis to death camp survivors and someone who has been in a motor vehicle accident diminishes the magnitude of the stressor and the significance of PTSD.

There is, of course, another way to honor those whose mental illness is the result of war, in line with Andreasen's original insight.  Instead of their own diagnosis, we might give them a Purple Heart.

Next up: Treatment and Prevention.

U.S. Army Soldiers attached to 3rd Squadron,
2nd Cavalry Regiment patrol and search for weapons
or Improvised Explosive Devices (IED) during a clearing mission
photo in public domain

5 comments:

  1. Hey, Willa. Very interesting piece. Question for you: why should the significance of the event matter? Isn't it more about the vulnerability of the brain? Yes, the event is the proximate cause. But some brains are resilient to even the worst event.

    I think you can see where I'm going with this ...

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  2. Readers: Here is the context to this discussion: Since the DSM V turned out to be a piss-poor job, John has been writing the People’s DSM. It’s a work in progress at http://knowledgeisnecessity.blogspot.com/ It begins on the post for March 15, and I recommend it to your reading.

    John: You’re going in one of two directions. The simpler is to keep it under Anxiety Disorders, but to rewrite that section in a more general way. The more radical is to subsume PTSD under Anxious Depression. The really radical is to subsume the whole of anxiety disorders under anxious Depression. I await further installments. :-)

    While I would eliminate the specificity of the traumatizing event, there IS reason to retain its significance. There are three reasons: symptoms, treatment, politics.

    Okay -- that's where I started in response to your comment. After I expanded on each, I then wanted to add research as a fourth, and realized it was time to turn it into a future post.

    So just one more specific answer: Most brains ARE more resilient. But the vulnerability of the brain isn't enough to account for the illness. For those with PTSD, it is the event that makes the brain's vulnerability a problem. Now the most traumatic event may have been in the past, but for a diagnosis of PTSD, the more recent event is the trigger.

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  3. Hey, Willa. How about blowing the categories wide open? Why not come up with something called "Stress Disorders," and see what we can fit into it? Think of this as a mind exercise for right now.

    Here goes:

    Anxiety
    PTSD
    Some other version of trauma
    Stress-induced depression (I have this down in the People's DSM as "reactive depression)
    Stress-induced psychosis
    Stress-induced substance/alcohol abuse
    Borderline personality disorder
    Antisocial behavior

    In many ways, this goes back to the DSM-I of 1952 with "schizophrenic reaction" and "manic-depressive reaction," but now we have some brain science to lend support to this.

    Do you want to take it from there?

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  4. Nope -- That's your blog, not mine, and I'm not helping you with your homework. I dropped that class after paradigm-shifting in the church for the last five years. You might even say I changed my major and am now in the intro classes of the new one.

    Best of luck!

    ReplyDelete
  5. What? You're not up to a little light paradigm-shifting? :)

    ReplyDelete