Tuesday, February 16, 2010

My DSM-5 Report Card: Grading Depression - Part I

This is the first in a series of report cards that grades the homework turned in last week by the DSM-5 Task Force. Our first assignment: Depression.

First, some background ...

According to statistics cited on the NIMH website, major depression is the leading cause of disability in the US and affects 6.7 percent of Americans in any given year. Plus major depression is a major component to bipolar disorder, affecting another 2.6 percent of the US population each year. In addition, dysthymia (major depression lite) accounts for an additional 1.5 percent.

An illness of this dimension literally comes equipped with its own gravitational field. Thus, few psychiatric diagnoses make sense without some reference to depression, be it anxiety or schizophrenia or borderline personality disorder.

This means that if the people responsible for coming up with a new version of DSM depression get it wrong, then the whole document - together with the whole field of diagnostic psychiatry - is going to be out of alignment.

Fortunately, everyone knows what depression is, right? Um, not exactly. Early versions of the DSM recognized the highly complex nature of the illness at the expense of confusing just about everyone and thus influencing no one. The DSM-III of 1980 and its successors (the DSM-III-R, the DSM-IV, and the DSM-IV-TR) went for simplicity and clarity, which seemed to please just about everyone, except maybe patients.

The major knock on depression as we know it is that it is a catch-all diagnosis for all manner of things going wrong. But this is its major appeal, as well. One one hand, not enough patients are getting better on meds and therapies designed to combat this simultaneously mysterious and obvious entity called depression. On the other hand, just enough are.

At issue for the DSM-5’s Mood Disorders Work Group is how these major contradictions can be reconciled.

Time to start grading ...

The symptom checklist

This was a masterstroke from those who brought us the DSM-III. So much so, that we tend to think of the checklist as something that existed since before the dawn of time and that is based on pure science rather than being pulled out of thin air. Even though the current DSM recognizes several different forms of depression, everything originates from this (five of) nine-item menu.

Critics have identified a number of major problems with the list, namely:
  • It is biased toward identifying depression in women rather than men (such as “appears tearful”).
  • It fails to identify the patient’s predominant state of mind. For instance, it is possible to check off “feeling depressed,” followed by “significant weight loss,” “insomnia,” “psychomotor agitation,” and “fatigue.” Voila! Major depression, but what does that tell us? Is one vague mental symptom followed by four physical ones truly depression?
  • It fails to identify the patient’s predominant state of mind (again). Sad? Agitated? Unmotivated? Feeling hopeless? Overthinking things? Excruciating psychic pain? Yes, we know it’s depression. But what is really going on?
On the other hand, the list has been in service for 30 years. It may not be perfect, but it does give us a reasonable approximation of a condition that so profoundly lays waste to so many. So why change it? This was the approach adopted by the workgroup.

Unfortunately, this was the safe option that gave us nothing to think about, that squelched a conversation that we badly need to be having, and that put the interests of monied stake-holders (such as the insurance industry) over the needs of patients.

Grade: F-minus.
Mixed Anxiety Depression

This is a wholly new and separate diagnosis, distinct from major depression. The workgroup recognized that nearly 60 percent of those with major depression also experience anxiety, which adversely affects patient outcomes.

The new diagnosis would acknowledge that one need not experience full-blown major depression or full-blown anxiety to wind up seriously distressed and incapacitated. A little bit of each will do. Thus, Mixed Anxiety Depression calls for just three or four depression symptoms (one which must include either feeling depressed or loss of pleasure), plus “anxious distress” which involves such things as “irrational worry.”

The recognition of anxious-depression is long-overdue, but since it was already listed in the DSM-IV appendix as deserving of future consideration, one cannot give the current workgroup credit for putting the issue on the table. Moreover, there is no mention of how “agitated depression” and other types of “mixed states” may fit into the picture.

Grade: C.

Mixed Episodes

The current DSM only recognizes mixed depression-mania states as occurring in bipolar I, and only in the ridiculously limited context of full-blown mania combined with full-blown depression. The DSM-5 would restore a measure of sanity by acknowledging that mixed states can occur in bipolar II, as well.

How this fits into unipolar depression is unclear. On one hand, the workgroup expressly rules out unipolar depression if the patient had ever experienced a mixed episode. On the other hand,
with no explanation, the workgroup adds the specifier, “with mixed features.” Huh?

There is good evidence that many individuals with unipolar depression experience mania/hypomania symptoms in their depressions, not enough to rate a diagnosis of bipolar, but enough to raise their levels of distress and make their depressions more difficult to treat.

On this very important issue, the DSM-5 workgroup has not handed in its homework.

Grade: Incomplete.

We’re not finished. Stay tuned for Part II of the Depression Report Card ...

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