Ever
since it was minimal brain damage, or hyperactivity disorder, minimal brain
dysfunction, or ADD, or DSM-IV Attention Deficit Hyperactivity Disorder (ADHD),
people have been curious to know how many of them there are. Early local studies
placed
the numbers somewhere between 2% and 20%.
This
remarkable disparity obviously raises the question of who defines what a “case”
is, the methods used to arrive at the
numbers, and the relationship between the “diagnosis” and the treatments that
result. Until recently all studies were estimates made from clinical samples or
local regional studies without regard to the factors of age limits, ethnicity, demographics or
gender. Sometimes
it is the numbers relating to use of stimulant drugs and their misuse or abuse
that prompts the question of how many ADHD there are. So in this presentation I
will focus on all three questions: The
nature of the
“diagnosis”, the impact of diagnosis on the numbers, and the role of
pharmacotherapy and other factors in determining the numbers.
Bell
was a famous
Scottish lecturer at the medical school of the University of Edinburgh in the 19th century. Bell emphasized importance of close observation in making a diagnosis. To illustrate this, he would often pick a stranger and, by observing him, deduce his occupation and recent activities, These skills caused him to be considered a pioneer in forensic science.
Scottish lecturer at the medical school of the University of Edinburgh in the 19th century. Bell emphasized importance of close observation in making a diagnosis. To illustrate this, he would often pick a stranger and, by observing him, deduce his occupation and recent activities, These skills caused him to be considered a pioneer in forensic science.
Doctor
Sir Arthur Conan Doyle was the most famous student of Bell, passing on Bell’s
wisdom of close observation in diagnosis to his creation, Sherlock Holmes, and
himself as Holmes’ companion, the bumbling Dr. Watson. A
constant reminder of Holmes to Watson was, “You see Watson, but you do not
observe,” implying that seeing without close observation led to mistaken
conclusions.
An apocryphal story illustrates the key point: Holmes & Watson
are on a camping trip, and lying on their sleeping bags and peering at the sky,
Holmes asks, “What do you see, Watson?” Watson replies, Well Holmes, I see the
milky way, and countless stars and…” Holmes interrupts and points out, “You
fool Watson, someone has stolen the tent! YOU SEE BUT YOU DO NOT OBSERVE!”
Justice
Potter Stewart made this observation when in the midst of a Supreme Court
debate on the definition of pornography. Apparently seeing without further
thought also infects the legal profession!
Early prevalence estimates suffered from generalizing from clinical samples without attention to
the demographic, gender, ethnicity, and diagnostic rules.Many
of the studies used local school districts as the unit of observation and
seldom distinguished between teacher and parent definitions or verified
physician diagnosis.
Many
of the studies used “hyperkinesis” as
the defining syndrome marker. Easily seen, but a characteristic of many
conditions that would require more exact observation to sort out comorbities or
other diagnoses. Nevertheless, one sees here such a diverse range of prevalence
estimates that it casts doubt upon the validity of all.
An
exception to most of the other studies was a very comprehensive approach
by Bosco and Robin in Central Michigan in 1980.
They used verified physician diagnoses, and data from both parents and
teachers, paying careful attention to demographic factors.
They
received data from 9293 teachers and 7248 parents. Rates of 3.16% and 3.38%
“represent the highest possible prevalence rates obtainable from our data…” The
VERIFIED prevalence for physician diagnosis was only 2.92%. Only
1.79% had been treated with stimulants in the previous 5 years. This report
deserves more creditability than all of the extreme numbers. Bosco, J. J., & Robin, S. S. (Eds.).
The
Hyperactive Child and Stimulant Drugs. Chicago: University of Chicago
Press, 1977.
J
Am Acad
Child Adolesc
Psychiatry. 2000 Aug;39(8):975-84; discussion 984-94.
Stimulant treatment for children: a
community perspective.
Source
Department
of Psychiatry and Behavioral Sciences, Duke University Medical Center, Durham,
NC 27710, USA.
Abstract
OBJECTIVE:
To
examine the use of prescribed stimulants in relation to research diagnoses of
attention-deficit hyperactivity disorder (ADHD) in a community sample of
children. METHOD:
Data
from 4 annual waves of interviews with 9- to 16-year-olds from the Great Smoky
Mountains Study were analyzed. RESULTS:
Over
a 4-year period, almost three quarters of children with an unequivocal
diagnosis of ADHD received stimulant medications. However, girls and older
children with ADHD were less likely to receive such treatment. Most children
with impairing ADHD symptoms not meeting full criteria for DSM-III-R ADHD did
not receive stimulant treatment. Stimulant treatment in this group
was significantly related to the level of symptoms reported by parents and
teachers and was much more common in individuals who met criteria for
oppositional defiant disorder. The majority of individuals who received stimulants
were never reported by their parents to have any impairing ADHD symptoms. They
did have higher levels of nonimpairing
parent-reported ADHD symptoms, higher levels of teacher-reported ADHD symptoms,
and interviewer-observed ADHD behaviors, but these typically fell far below the
threshold for a DSM-III-R diagnosis of ADHD.CONCLUSIONS:In
this area of the Great Smoky Mountains, stimulant
treatment was being used in ways substantially inconsistent with current
diagnostic guidelines
"Stimulant treatment…was much more common in individuals who met criteria for oppositional defiant disorder. The majority of individuals who received stimulants were never reported by their parents to have any impairing ADHD symptoms [which] typically fell far below threshold for a DSMiii-R diagnosis of ADHD."
By
cleverly intermixing questions about prescriptions for ADHD medicines with
questions about doctors diagnosing ADHD, telephone interviews of parents
produces a wide range of “cases” for determining prevalence.
To
be sure, this method produces some curious data. For example, why is the
prevalence so low in the southwest? And what about Illinois? We might
understand Texas, where the death rate from executions may be snuffing out
potential ADHD candidates. But what of North Carolina, with the highest rate
near 15 percent?
And
no, it is not because I happen to live there! It happens to be one of the
lowest states for using the Conners’ scales, with cultural lag possibly
accounting for North Carolinians fondness for the Achenbach Scales (Just kidding). Actually, research recently showed that the explosion of "diagnoses" in NC is caused by educational policies which shifted ADHD from regular classes to avoid the reimbursement penalties of new requirements imposed by end of year testing.
•Children
3-17
•5
million children (9% of this age group) have ADHD
•Boys
(12%) twice as likely as girls to have ADHD
•Incidence
of ADHD diagnoses increased an average of 3% annually between 1997-2006
•In 17
regional or multisite studies utilizing DSM3 or DSM4 prevalence rates ranged
between 2% to 26%
•Data
obtained from The National
Health and Nutrition Examination Survey (NHANES), an annual multistage
probability sample survey of non-institutionalized US population
•Data from 2001 to 2004 obtained on 3082 children
ages 8-15 using DISC IV by telephone.
•8.7% met DSM-IV criteria for ADHD
in the year prior to the survey = 2.4 million children
•An additional 3.3% did not meet
DSM-IV criteria but had both a parent-reported prior diagnosis of ADHD and
treated with stimulants at some time during the past 12 months
•Rates for boys were higher than girls
(11.8%) vs
5.4%).
•Of those meeting DSM-IV criteria, only
48% reported receiving a diagnosis by a health professional in the prior year
•38.8% who met criteria reportedly
received medication at some time in the prior year.
Froelich et
al choose to interpret the 3.3% who were medicated but not meeting DSM criteria
as those correctly diagnosed and successfully treated and thus no longer
showing symptoms. But one could equally argue that they NEVER met ADHD criteria
and were given stimulants incorrectly in children who were in fact
miss-diagnosed.
Note
that their estimates of that group plus the 8.7% reaches the phenomenal level
of 15% prevalence, just as the upper bound estimated by the CDC.
The
consensus conference was modeled (it might appear) on the example of the Spanish
Inquisition searching for witches. One might imagine that here I am
Pleading the case for ADHD as a reliable diagnostic category. I said, in the 15 minutes I had to present, “Formal
diagnostic criteria for the disorder underwent rapid changes as new syntheses
and accumulation of data from field trials took place. The fact that the
concept of ADHD has evolved with changing evidence should be taken as a
strength, not as a sign of unreliability or vague conceptualization.
Comprehensive review of the evidence regarding diagnosis and treatment carried
out by independent expert medical reviewers concludes that diagnostic criteria
for ADHD are based on extensive empirical research and, if applied
appropriately, lead to the diagnosis of a syndrome with high interrater
reliability, good face validity, and high predictability of course and
medication responsiveness (Goldman, Genel, Bezman, et al., 1998)."
However, I qualified my judgment by adding, "Important
areas of our knowledge about ADHD remain to be clarified. Developments in
cognitive neuroscience point to the multidimensional nature of both attentional
processes and activity level, yet these concepts are poorly operationalized by
current symptomatic criteria. Neuropsychological studies demonstrate a clear
heterogeneity in samples of ADHD defined solely by symptomatic criteria
(Conners, 1997). Doubts have been raised about the current nosological
subtyping and the possibility that inattention and hyperactivity-impulsivity
reflect separate disease entities (Barkley, 1998b). Current
diagnostic criteria require that symptoms be more frequent and severe than are
typically observed in individuals at a comparable level of development
(American Psychiatric Association, 1994), but marked variations in the
application of this rule lead to serious underdiagnosis or overdiagnosis,
resulting in excesses or deficiencies of pharmacologic treatments (Angold,
Costello, 1998).
The
embarassment of
riches from neuroimaging studies reflects a poor understanding of any
specificity for the neural basis of ADHD. The high levels of comorbidity of
ADHD with oppositional, conduct, and mood disorders also call into question the
specificity of the definition of the disease and whether current criteria are
sufficient to allow further understanding of the neurobiology of the syndrome."
The list of speakers at the conference attests to the wide range of expertise from many different disciplines regarding the reliability and validity of ADHD. What
a knowledgeable group; every body who knows anything about ADHD in 1998! This
formidable group had to submit highly structured and detailed chapters in
advance to the group of prominent but non-involved judges whose job was to
determine the validity and reliability of diagnosis of ADHD and the value of
its treatments.
An impartial group of scientists and scholars served as a judging panel based on the oral presentations and extensive documentation provided to them by the speakers
Mark
Vonnegut, son of Kurt Vonnegut, is a very interesting and funny man. A
pediatrician, his memoir details his days of severe psychosis and
hospitalizations.
Despite
this extraordinary handicap he managed to become a pediatrician and spokesman
for the plight of the mentally ill.
When
the Director of NIMH at the consensus conference called upon the eminent panel
for comments about what they had heard (and presumably read), Mark was the only
one with the courage to speak up. He inadvertently supplied the rubric shared
by the vast body of providers and critics about ADHD. Once again, seeing
without observing. Had the eminent panel actually read all of the detailed
documents? Was he the only one?? Probably not.
Compilation
of studies is another method for establishing prevalence. Unlike the CDC and Froelich’s data
on a national representative sample of telephone surveys of a parent, these
data appear to give much more modest prevalence estimates.
These
data show the rapid increase in both diagnosis and treatments with
stimulant drugs over a 10 year period.
The
increase over a 5 year span shows that the greatest changes are the increases in
diagnosis of young adults
The seriousness of the flood of stimulant medications is shown by the data from emergency rooms between 2005 and 2010. Visits involving ADHD and stimulants increased from 13,379 to 31,244 visits over the 10 year span.
The
problems of diagnosis of ADHD are compounded with adults for many reasons. The
need for a sound clinical history is obviously absolutely essential.
Although
parents are not necessarily available for gaining critical developmental
information, the contribution of significant others who know the patient well
is often practicable and important for verifying the subjective report by the
patient.
Depressed Dopamine Activity in Caudate
and Preliminary Evidence of Limbic Involvement in Adults With
Attention-Deficit/Hyperactivity Disorder.
Nora
D. Volkow, MD;
Gene-Jack Wang, MD; Jeffrey Newcorn, MD; Frank Telang, MD;
Mary V. Solanto,
PhD; Joanna S. Fowler, PhD; Jean Logan, PhD; Yeming Ma, PhD; Kurt Schulz, PhD; Kith Pradhan, MS;
Christopher Wong, MS; James M. Swanson, PhD
Arch Gen Psychiatry. 2007;64(8):932-940.
doi:10.1001/archpsyc.64.8.932.
Regression
slopes
between changes in dopamine (DA) in caudate and in putamen and scores on
Conners Adult ADHD Rating Scales (CAARS) section E (DSM-IV
symptoms of inattention) in subjects with attention-deficit/hyperactivity
disorder (ADHD). Correlations correspond for left caudate (r = −0.49,
P < .04),
right caudate (r = −0.56, P < .02),
left putamen (r = −0.61, P < .008),
and right putamen (r = −0.71, P < .001).
Careful
look at the CAARS “Inattention” factor shows that the symptoms are primarily
those of Executive Dysfunction.
Executive dysfunction is a characteristic of many psychiatric disorders, emphasizing the importance of thorough diagnostic workup for establishing that the client has ADHD and not one of the many alternatives
Dr. Frances points out how the new criteria for DSM-5 have opened the doors for a huge increase in the number of normal behaviors which will now be interpreted as mental illnesses. He uses data from his own experience of losing his wife to illustrate how the new criteria for depression mistake normal bereavement for a mental disorder.
Data show already that the expected increase has affected "diagnoses" of ADHD.
