Saturday, June 15, 2013

The past, present and future of psychiatric diagnosis - by ALLEN FRANCES


PERSPECTIVE

The past, present and future of psychiatric diagnosis


ALLEN FRANCES

Department of Psychiatry, Duke University, Durham, NC, USA


Modern descriptive psychiatry was born two centuries
ago in the classification of Pinel, was later systematized in
the textbook of Kraepelin, and was then expanded by Freud
to include outpatient presentations previously seen by neurologists. Brain science also flourished in the second half of
the 19th century and has enjoyed a second revolutionary
advance during the past thirty years. Unfortunately, however, the attempt to explain psychopathology using the remarkable findings of neuroscience has thus far had no
impact on psychiatric diagnosis or treatment. The crucial
translation from basic science to clinical practice is necessarily even more difficult in psychiatry than in the rest of
medicine, because the human brain is the most complicated thing in the known universe and reveals its secrets
slowly and in small packets.
Psychiatric diagnosis must therefore still rely exclusively on fallible subjective judgments, not on objective biological tests. In the not too distant future, we will finally
have laboratory methods for diagnosing Alzheimer’s disease, but there is no pipeline of promising tests for any of
the other mental disorders. Biological findings, however
exciting, have never been robust enough to become testworthy, because the within-group variability always drowns
out the between-group differences. It appears certain that
we will be stuck with descriptive psychiatry far into the
distant future.
There have been two crises in confidence in descriptive
psychiatry: the first was in the early 1970s, the second is
occurring right now with the publication of DSM-5. The
earlier crisis was occasioned by two highly publicized
studies that exposed the inaccuracy of psychiatric diagnosis and threw into serious question the credibility of psychiatric treatment. A landmark study proved that British
and US psychiatrists came to radically different diagnostic
conclusions when viewing videotapes of the same patient
(1). And Rosenhan (2) exploded a bombshell when his
graduate students were kept in psychiatric hospitals for
extended stays after claiming to hear voices, despite the
fact that they behaved completely normally once they
were admitted. Was psychiatry entitled to a place among
medical specialties if its diagnoses were so random and its
treatments so nonspecific, especially when the other specialties were just then becoming increasingly scientific?
Psychiatry’s response was dramatic and effective. The
DSM-III, published in 1980, featured detailed definitions
of mental disorders that, when used properly, achieved reliabilities equivalent to much of medical diagnosis. The
DSM-III soon stimulated its own revolution, quickly transforming psychiatry from research stepchild to research
darling; in most medical schools, the department of psychiatry now ranks behind only internal medicine in research
funding.
But psychiatric diagnosis is now facing another serious
crisis of confidence, this time caused by diagnostic inflation. The elastic boundaries of psychiatry have been steadily expanding, because there is no bright line separating
the worried well from the mildly mentally disordered.
The DSMs have introduced many new diagnoses that
were no more than severe variants of normal behavior.
Drug companies then flexed their powerful marketing
muscle to sell psychiatric diagnoses by convincing potential patients and prescribers that expectable life problems
were really mental disorders caused by a chemical imbalance and easily curable with an expensive pill.
We are now in the midst of several market-driven diagnostic fads: attention-deficit/hyperactivity disorder (ADHD)
has tripled in rates in the past twenty years; bipolar disorder
has doubled overall, with childhood diagnosis increasing
forty-fold; and rates of autistic disorder have increased by
more than twenty-fold (3). In the US, the yearly prevalence
of a mental disorder is reported at 20–25%, with a 50% lifetime rate (4), and Europe is not far behind (5). A prospective
study of young adults in New Zealand has reported much
higher rates (6) and another of teenagers in the US found an
astounding cumulative 83% rate of mental disorders by age
21 (7).
The expanding concept of mental disorder brings with it
unfortunate unintended consequences. Only about 5% of
the general population has a severe mental disorder; the
additional 15–20% have milder and/or more temporary
conditions that are placebo responsive and often difficult
to distinguish from the expectable problems of everyday
life. Yet an amazing 20% of the US population now takes a
psychotropic drug (8) and psychotropic drugs are star revenue producers – in the US alone $18 billion/year for antipsychotics, $12 billion for antidepressants, and $8 billion
for ADHD drugs (9). And 80% of psychotropic drugs are
prescribed by primary care physicians with little training
and insufficient time to make an accurate diagnosis (10).
There are now more overdoses and deaths from prescribed
drugs than from street drugs.
And the investments in psychiatry are badly misallocated, with excessive diagnosis and treatment for many
mildly ill or essentially normal people (who may be more
harmed than helped by it), and relative neglect of those
with clear psychiatric illness (whose access to care in the
US has been sharply reduced by slashed mental health
budgets) (11). It is no accident that only one third of
111people with severe depression get any mental health care
or that a large percentage of the swollen US prison population consists of psychiatric patients with no place else to
go (12). A recent meta-analysis shows the results of psychiatric treatment to equal or surpass those of most medical specialties (13), but the treatments must be delivered
to those who really need them, not squandered on those
likely to do as well or better on their own.
This disparity between treatment need and treatment
delivery is about to get much worse. The DSM-5 has introduced several new disorders at the fuzzy and populous border with normal and has also loosened requirements for
many of the existing disorders. The biggest problems are
removing the bereavement exclusion for major depressive
disorder, adding a very loosely defined somatic symptom
disorder, reducing the threshold for adult ADHD and posttraumatic stress disorder, adding a diagnosis for temper
tantrums, introducing the concept of behavioral addictions,
combining substance abuse with substance dependence,
and adding mild neurocognitive disorder and binge eating
disorder.
The DSM-5 has been prepared without adequate consideration of clinical risk/benefit ratios and has not calculated the large economic cost of expanding the reach of
psychiatry. It has been unresponsive to the widespread
professional, public, and press opposition that was based
on the opinion that its changes lacked sufficient scientific
support and often defied clinical common sense. And
a petition endorsed by fifty mental health associations
for an independent scientific review, using methods of
evidence based medicine, was ignored.
There will be no sudden paradigm shift replacing descriptive psychiatry with a basic explanatory understanding of the pathogeneses of the different mental disorders.
This will be the gradual and painstaking work of many
decades. In the meantime, we must optimally use the
tools of descriptive psychiatry to ensure reliable and
accurate diagnosis and effective, safe, and necessary
treatment. It is time for a fresh look. The preparation
of the ICD-11 provides an opportunity to re-evaluate
psychiatric diagnosis and to provide cautions against its
over-inclusiveness.
References
1. Kendell RE, Cooper JE, Gourlay AJ et al. Diagnostic criteria of
American and British psychiatrists. Arch Gen Psychiatry 1971;
25:123-30.
2. Rosenhan DL. On being sane in insane places. Science 1973;179:
250-8.
3. Batstra L, Hadders-Algra M, Nieweg EH et al. Child emotional
and behavioral problems: reducing overdiagnosis without risking
undertreatment. Dev Med Child Neurol 2012;54:492-4.
4. Kessler RC, Berglund P, Demler O et al. Lifetime prevalence and
age-of-onset distributions of DSM-IV disorders in the National
Comorbidity Survey Replication. Arch Gen Psychiatry 2005;6:593-
602.
5. de Graaf R, ten Have M, van Gool C et al. Prevalence of mental
disorders and trends from 1996 to 2009. Results from the Netherlands Mental Health Survey and Incidence Study-2. Soc Psychiatry Psychiatr Epidemiol 2012;47:203-13.
6. Moffitt TE, Caspi A, Taylor A et al. How common are common
mental disorders? Evidence that lifetime prevalence rates are
doubled by prospective versus retrospective ascertainment. Psychol Med 2010;40:899-909.
7. Copeland W, Shanahan L, Costello EJ et al. Cumulative prevalence of psychiatric disorders by young adulthood: a prospective
cohort analysis from the Great Smokey Mountains Study. J Am
Acad Child Adolesc Psychiatry 2011;50:252-61.
8. Medco Health Solutions Inc. America’s state of mind. www.
medco.com.
9. IMS Institute for Healthcare Informatics. The use of medicines in
the United States: review of 2011. www.imshealth.com.
10. Mark TL, Levit KR, Buck JA. Datapoints: psychotropic drug prescriptions by medical specialty. Psychiatr Serv 2009;60:1167.
11. Wang PS, Aguilar-Gaxiola S, Alonso J et al. Use of mental health
services for anxiety, mood, and substance disorders in 17 countries in the WHO World Mental Health Surveys. Lancet 2007;
370:841-50.
12. Fuller Torrey E. Out of the shadows: confronting America’s mental illness crisis. New York: Wiley, 1997.
13. Leucht S, Hierl S, Kissling W et al. Putting the efficacy of psychiatric and general medicine medication into perspective: review of
meta-analyses. Br J Psychiatry 2012;200:97-106.
DOI 10.1002/wps.20027

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