Tuesday, July 19, 2011

Personality Disorders - The DSM-5 Has Another Go

On June 21, the DSM-5 workgroup responsible for bringing order to personality disorders substantially changed what it originally posted on the DSM-5 site back in Feb, 2010. Most of us could see this coming. As the workgroup explained in its most recent update: “All parts of the model have been simplified and streamlined in response to comments received and to critiques in the published literature.”

A little background ...

Unlike the rest of the DSM-5, the 2010 roll-out of Personality Disorders was no mere light dusting of the status quo. This was a major home-improvement, a hugely ambitious effort that sought to integrate two different ways of looking at mental illness - categories (as in “which one?”) with dimensions (as in “how much?”) into something workable.

Personality, after all, cannot be easily categorized. Yet, we do need categorical bearings. Dimensionality is far more in sync with clinical reality, yet much more difficult to sort and freeze into comprehensible diagnostic nuggets. The workgroup’s answer to this dilemma was essentially a modular system. (The diagnostic literature refers to “hybrid,” but “modular” - think IKEA - is far more accurate.)

Thus, the DSM-5 retained diagnostic categories such as Borderline and Antisocial, but built them with interchangeable parts. Accordingly, individuals with either illness may have the following hostility “personality trait” in common:

Persistent or frequent angry feelings; anger or irritability in response to minor slights and insults ...

This particular trait is a subset of the antagonism “domain.” But quick comparison between the two categories reveals very different loadings. Those with antisocial have far more antagonism traits (such as callousness) than those with borderline. (The new version lists only one antagonism trait for borderline, down from two in the old version.) Meanwhile, borderline comes heavily loaded in negative affectivity traits (such as emotional lability) while we see nothing of the sort in antisocial.

Thus, a few shared traits, but clearly defined separation, which hopefully results in less diagnostic confusion.

That brings us to the dimensional element. In their initial roll-out, the DSM-5 essentially took apart and reassembled the exact same categorical bits and pieces in a different way to see “how much” of say borderline or antisocial (or avoidant or schizotypy or obsessive-compulsive) one has.

In other words, the real world is not black and white, much less divided into all-or-nothing choices. Imagine: Under the DSM-IV, a person who is one symptom shy for not only borderline, but also antisocial and narcissism is technically normal. How crazy is that? The DSM-5’s solution was to look at the entire gamut of personality as something analogous to blood pressure, from healthy to unhealthy, with an eye on the various loadings.

One may or may not require clinical attention, but a dimensional assessment can be an enormous help in knowing thyself.

Great concept, but the DSM-5’s first draft was monumentally unwieldy, calling for clinicians to rate 37 facets making up six domains on a four-point scale. Who has time for that?

It was back to the drawing board for the DSM-5 work group. Eighteen months later, the blood pressure principle remains the same, but now, in place of version number one, we have a new dimensional entity called Personality Disorder Trait Specified (PDTS).

Oh-oh! Are we in for yet another mouthful of diagnostic alphabet soup, this time looking like a misspelling of PTSD? Or is the DSM-5 about to make life easier for us?

More to come ...

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