Is mental illness categorical or dimensional?

In my last post I discussed the politics of psychiatric nosology and the revision of the Diagnostic and Statistical Manual of Mental Disorders (DSM).  While the machinations behind specific disorders are fascinating, it is easy to miss the forest for the trees.  The basic idea of dividing mental distress and disability into diagnostic categories is itself controversial.

The DSM takes the stance that there are discrete "bins" (disorders) that individual patients can be sorted into.  For over 25 years there has been discomfort in the professional community about this, particularly in the case of personality disorders (Axis II of the DSM).  One of the architects of Axis II, Theodore Millon, PhD, objected to purely categorical personality diagnosis.  His website says:

It is Millon's view that there are few pure variants of any personality prototype. Rather, most persons evidence a mixed picture, that is, a personality that tends to blend a major variant with one or more subsidiary or secondary variants.

Statistics on Axis II disorders seem to bear this out.  Many studies show great overlap between categories, and many patients fit into more than one.  Clinical experience concurs: The patients I see are rarely "classic" cases of anything; everyone is unique.  Even everyday life experience suggests that personality features exist on a continuum:  One person is a bit detail-oriented, another is mildly obsessive, and another has serious problems with obsessiveness.  Yet the current DSM-IV-TR only defines "obsessive-compulsive personality disorder" (and allows mention of "obsessive compulsive personality traits," but this doesn't count as a disorder).  No nuance, no matter-of-degree.  Why do we have such ham-handed tools to describe psychiatric problems?

One reason is that psychiatry is a branch of allopathic Western medicine.  Unlike, say, traditional Eastern healing, we think in terms of disease categories.  And this fits fairly well for the most severe Axis I psychiatric disorders, such as schizophrenia.  The German psychiatrist Emil Kraepelin founded contemporary scientific psychiatry in the late 1800s by distinguishing the pattern of symptoms in schizophrenia ("dementia praecox") from that in manic depression.  In the early-to-mid 20th century, Freudian theory deflected such categorization, but it re-emerged as the dominant paradigm since the publication of DSM-III in 1980.  The 1990s "Decade of the Brain" heralded intensive research efforts to understand mental disorders from a medical perspective.  Today the vast majority of published psychiatric research is biomedical in nature, facilitated by the DSM's categorical framework.

In contrast to the medical psychiatric tradition, psychology has long pursued dimensional features of personality using empirical data.  Perhaps best known is the Five Factor Model.  Such models capture the variability and nuance of personality, but do not make sharp normal-versus-abnormal distinctions.  Each person exhibits one factor to a certain degree, the next factor to another degree, and so forth.  The combinations are nearly infinite.

The good news is that organized psychiatry is waking up to the value of dimensional assessment.  Position papers (e.g., here, here, and here) have long argued for this with respect to Axis II.  As working groups now meet to plan DSM-V, dimensional adjuncts are being considered for all traditional categorical diagnoses.

Is mental illness categorical or dimensional?  The "real" answer, I suspect, is that some psychiatric disorders will eventually be understood to have biological origins.  Schizophrenia will likely go the way of general paresis (syphilis) and Alzheimer's Disease:  When the medical cause of a psychiatric condition is finally understood, it is no longer considered a psychiatric condition.  It becomes the province of neurology, infectious disease, or another branch of medicine.  Psychiatry is left with conditions that defy medical explanation.  This is why I feel that, ultimately, dimensional factors are an irreducible feature of psychiatry.  Whether understood using Freudian psychodynamics, learning theory, or another psychological paradigm, human emotions and behavior will always be more subtle and nuanced than a categorical nosology can describe.

Laws, Sausages, and Psychiatric Nosology

Laws are like sausages. It's better not to see them being made.

Otto von Bismarck, German Prussian politician (1815 - 1898)

The Diagnostic and Statistical Manual of Mental Disorders (DSM), published periodically by the American Psychiatric Association (APA), aims to catalog all recognized mental disorders.  As the name implies, it is used both for clinical diagnosis and for various statistical (population) uses.  I previously posted how social judgments are inevitable in such a catalog; little wonder DSM has long served as a lightning rod for social debates over what is normal versus abnormal.

The fourth edition (DSM-IV) was published in 1994, followed by a minor "text revision" (DSM-IV-TR) in 2000.  Groups of psychiatrists are now drafting sections of DSM-V, due out in 2012.

It would be nice to imagine that the process of creating and updating DSM is scientific and unbiased.  However, like laws and sausages, psychiatric nosology (disease classification) is more palatable the less one notices how it is made.  As reported in today's New York Times, putative disorders such as compulsive shopping, sexual fetishes, and binge eating have their advocates and detractors.  Transgender people have a personal stake in whether "strong and persistent cross-gender identification" remains a mental disorder.  (Interestingly, the stigma of this diagnosis is offset by its utility in obtaining insurance coverage for gender-reassignment surgery and other treatment.)  This recalls debates over the inclusion of homosexuality as a mental disorder in earlier editions of DSM.  Homosexuality was dropped as a diagnosis in 1973. It was replaced by “sexual orientation disturbance” and then “ego-dystonic homosexuality” before those, too, were dropped in 1987.

Anyone who imagines that these debates are coolly scientific is dreaming.  As social norms change, our notions of mental illness change with them.  The long-term trend has been an expansion of DSM, both in terms of dividing syndromes more finely, and also widening the scope of behaviors considered disordered.  Stakeholders include the APA itself, sole publisher of the 800,000+ copies of this essential tome; pharmaceutical companies who stand to gain or lose fortunes based on whether a particular human deviance is treatable with medication; insurers who cover treatment for disorders but not non-disorders; patients who either have a mental illness or don't; and scientists trying to collect data and make sense of the whole thing.

It is good to bear in mind that some disorders in DSM-IV-TR, like "nicotine dependence," do not seem very much like mental disorders — and that one is bound to stay.  Meanwhile, other maladies of the human spirit, like living a life devoid of meaning or purpose, are not listed in the current DSM, and are not likely to appear anytime soon.  In my next post, I'll discuss one aspect of psychiatric nosology, categorical versus dimensional ratings, that may improve DSM-V.  However, the inclusion of messy social judgments in DSM is with us for the duration, obscured in the finished product by careful prose, numerical labels for disorders, and a little quantitative data.  Laws and sausages aren't bad either — if you don't think about them too much.

The customer is not always right

I often remind psychiatry residents that while a patient's treatment preference is important, it does not take the place of their own evaluation.  It is a bittersweet irony that many of us are mistaken about, or repelled by, what would most help us.

Some patients, with depression for example, only consider medications, and have tried many to no avail.  Even after a dozen adequate but unsuccessful medication trials by past psychiatrists, some call me in desperation to ask whether the 13th, usually with the newest heavily promoted product, could be the miracle they seek.  I generally tell them -- right on the phone -- that it is unlikely.  I also assure them that if they come in for an evaluation anyway, I will respect both their preference and past experience.  What I don't tell them:  People who avoid psychotherapy because they fear having to face uncomfortable memories or feelings often end up getting the most benefit out of it.  By the end of our first in-person meeting, I hope to engage such a patient's curiosity about his or her emotional life as more than simply a collection of symptoms.

Conversely, some patients pursue psychotherapy for years, and would never dream of taking psychiatric medication ("mind-altering chemicals").  This makes excellent sense when the problem is based on personality factors and relationship issues.  But sometimes it's not.  Even the best psychotherapy won't quell the hallucinated voices of schizophrenia, nor the behavioral excesses of mania.  Some patients are too depressed or anxious to use psychotherapy.  (And sometimes the problem is medical, not psychiatric at all.)  At these times it becomes my duty to advise medication, to explain why I do, and to explore with the patient their concerns and hesitation.

Some research says the best treatment for depression is a combination of medication and psychotherapy.  This often seems to be the case for problems other than depression, too.  As a psychiatrist I can provide one or the other or both.  And on rare occasions, neither:  A few patients have come to me who do not have a treatable problem at all.

The challenge for psychiatrists and other mental health professionals is that patients choose their own providers; they select us knowing their own preferences, and ours.  Persons who seek medication and not psychotherapy will likely see a psychopharmacologist who will share their viewpoint and only discuss medication.  Even more often, persons who seek psychotherapy and not medications (or a medical perspective) will see therapists who are not physicians.  Despite the advantages -- there are many more non-psychiatrists to choose from, and the fees are usually lower -- patient self-selection carries the risk of confirming their own prejudices.  It may sound harsh, but the "customer" is not always right.  It is incumbent upon us professionals to look past patient preference to what is most apt to be helpful -- even if we do not provide it ourselves.

Schizophrenia among us

I met a young man recently in a setting having nothing to do with psychiatry or mental health. He politely introduced himself and tried to learn the names of the others around him. He seemed socially awkward but inoffensive, and after I left I didn't give the encounter much thought. However, I learned that soon thereafter he showed increasingly odd behavior. He talked to himself, breached social boundaries, and acted aggressively for no apparent reason. Others had to keep an eye on him, and eventually he was escorted peacefully off the premises. The possible causes of such behavior are myriad: brain injury, psychotropic drugs, medical illnesses such as delirium or thyroid disease, and many others. One possible cause is mental illness, specifically schizophrenia. Schizophrenia is surprisingly common, affecting over 1% of the total population. As with many other disorders, schizophrenia can be mild or severe. Only a small minority of sufferers are institutionalized; the great majority live in society with everyone else. The class of medications called neuroleptics (anti-psychotics) have helped to make this possible, although some people with mild schizophrenia can function without medication.

I do not know whether the young man I met has schizophrenia. It would be presumptuous of me to attempt to diagnose someone I met only briefly in a social setting. But our meeting did spark some thoughts about the symptoms and deficits of this disorder.

A major hallmark of schizophrenia is auditory hallucinations (voices). When people "talk to themselves," particularly if they do so without regard to others noticing, it may be in response to hallucinated voices. The voices can be ignored for a while if they are not too severe. At the other extreme, if insistent voices command the person to hurt himself or others, this is a very serious situation that usually requires hospitalization. Medications are often helpful in quieting auditory hallucinations.

(Thanks to cellphones, particularly those with wireless headsets, people seen "talking to themselves" could simply be on the phone.  More than once I've passed someone on the sidewalk and assumed one of these scenarios, only to realize seconds later it was the other.)

Delusions are also prevalent in schizophrenia, as well as in other disorders such as delusional disorder and manic psychosis. Medications help with delusions too, but not as quickly as with hallucinations.

There are also "negative symptoms" in schizophrenia which include lack of emotional expression and a decreased ability to initiate action or speech. These are more resistant to medication, although the "atypical" neuroleptics available for the past 15 years are of some benefit.

More subtle are the "thought process" changes in schizophrenia, and these are what came to my mind regarding the young man I met. Classically, schizophrenic thought is described as concrete. The ability to think abstractly, metaphorically, and symbolically is impaired. For example, in psychiatric evaluations patients are sometimes asked to interpret a proverb such as, "People in glass houses shouldn't throw stones." While most healthy individuals understand this is not literally about glass houses, many with schizophrenia will say something like, "because the glass will break." Likewise, people with schizophrenia often cannot understand jokes or indirect references in the speech of others.

It is a sad and isolated existence to be cut off from so much human interaction, unable to share in common emotional experience.  Much of the meaning and flavor of life is contained therein.  This is not to say that people with schizophrenia cannot lead productive and meaningful lives.  They can, but it's hard.  My "up close and personal" encounter with someone possibly suffering these challenges reminded me that compassion, not fear or disdain, is the most apt response to the tragedy of schizophrenia.

Long hours in medical and surgical residency

The New York Times health blog "Well" today posted:

A national panel of medical experts proposed significant and costly changes for training new doctors in the nation’s hospitals, recommending mandatory sleep breaks and more structured shift changes to reduce the risk of fatigue-related errors.

 The report was issued by the Institute of Medicine (IOM).  As expected, there are hundreds of comments on the blog.  Many established doctors defend current training practices (or lament the loss of even more grueling ones in the past) as the best way to get maximal experience during training.  Some residents also defend current practice, while others recount mistakes made while sleep-deprived, and call the system senseless.  Most self-identified laypeople condemn as obviously poor patient care a system where doctors work for over 24 hours without sleep.

Sleep deprivation during medical/surgical training has been an interest of mine since I was in training myself in the 1980s.  I even wrote a paper on it as a medical student.  This is my commentary I posted to the "Well" blog.  I invite your thoughts here.

I’m a psychiatrist involved in medical education my whole career. It’s a relatively easy specialty in terms of training hours. But I was a med student and had a medical internship like other MDs, and was appalled by the hazing justified as a necessary educational experience. Like a fraternity initiation, each generation of doctors imposes it on the next to keep medicine special, to maintain a sharp in-group/out-group distinction. It is also perpetuated institutionally thanks to the unbeatable economics of paying a highly trained, intelligent workforce minimum wage.

There is no way to learn everything in training, whether residency is 3 years or 10. The conceit that the current system teaches residents “everything they need to know” leads to calls to add residency years to make up for reduced hours. But how did we determine we’re teaching residents the “right” amount now?

In an era of evidence-based medicine it is medical training itself that resists the application of empirical science. Plenty of studies show cognitive and interpersonal deficits with sleep deprivation. There are none I’m aware of that show these effects can be trained out of people, nor that long call hours “teach” residents to make hard decisions in the middle of the night. If we rely on personal anecdotes, my experience says that sleep deprivation teaches trainees that working half-awake is acceptable as long as you survive the ordeal, that procedures are more important than talking with patients — there goes prevention and lifestyle changes — and that anyone who criticizes this heroic undertaking is a wimp who “just doesn’t get it.”

Certain rote practices like CPR or running a code improve with mindless repetition, but sensitive interpersonal skills (eg, discussing a patient’s cancer diagnosis) do not improve by “practicing” them over and over when you can’t think straight. The human qualities of great doctors — caring, sensitivity, interpersonal nuance — are profound gifts. It is a cruel and misguided system that devalues these gifts in order to to maximize the repetition of protocols and procedures.

Where to go from here?

1) Obviously, the IOM’s changes will cost money. Other countries with excellent health care systems have found a way, and we can too.

2) Medicine is already too complicated to sign-out (ie, hand off) patients in the informal way we do now. Electronic medical records with built-in error checking is inevitable in the near future. It’s a good thing, particularly at this error-prone step.

3) The “ownership” of patients is a real issue, and may be made worse by a shift-work mentality. The solution is not to avoid shifts — they are inevitable in any business that is open 24/7 — but to (re-)instill a cultural norm that caring about *people* is expected, and frankly more important than memorizing the last 5 days of electrolyte values. I’d rather be treated by a well-rested doctor who cares about me but has to look up the labs.

http://www.stevenreidbordmd.com/blog.html

— Steven Reidbord MD