ADHD: Is Objective Diagnosis Possible?

Psychiatry (Edgmont). 2005 Nov; 2(11): 44–53.

Published online 2005 Nov.

PMCID: PMC2993524

PMID: 21120096

ADHD: Is Objective Diagnosis Possible?

C. Thomas Gualtieri, MDcorresponding author and Lynda G. Johnson, PhD

Author information Copyright and License information Disclaimer

This article has been cited by other articles in PMC.

Go to:

Abstract

Although attention deficit/hyperactivity disorder (ADHD) is one of the most common cognitive disorders, the usual diagnostic procedures pursued by psychiatrists, neurologists, pediatricians, and family practitioners are based largely, if not exclusively, on subjective assessments of perceived behavior. The recommended approaches to ADHD diagnosis are reviewed, first from the perspective of the various expert panels, and then from the research literature upon which those recommendations are based. The authors agree that ADHD is a clinical diagnosis, and that the assessment of subjective reports can be systematic. But they propose that objective data should also contribute to the clinical diagnosis of ADHD; and that new computerized assessment technology can generate objective cognitive data in an efficient and cost-effective way. Computerized tests can also improve the assessment of treatment response over time.

Go to:

Introduction

Attention deficit/hyperactivity disorder (ADHD) is very much in the public eye. Increasing numbers of schoolchildren are diagnosed with the condition and millions of North American schoolchildren take ADHD medications. Members of college and graduate programs and test administrators for tests such as the Scholastic Achievement Test (SATs) are petitioned to make the necessary accommodations for people who are diagnosed with ADHD. What is a reasonable accommodation to one person may seem like “jumping the queue” to another.1 Some adult patients are not shy about visiting their new family practitioner and announcing they have ADHD and requesting amphetamines. Thirty years ago, on the heels of amphetamine epidemics and diet-pill excess, such a patient would likely get thrown out on his ear. It is no small measure of how things have changed that today this patient usually gets what he asks for.

The reported prevalence of ADHD is likely to excite a sense of urgency among the converted and skepticism among the dubious. Thirty years ago, the prevalence of ADHD was said to be 1 to 3 percent of all schoolchildren in North America;2 then it was 3 to 5 percent.3 In 1997, 3 to 10 percent of schoolchildren in North American were said to have ADHD.4,5 By 2002, the cumulative prevalence was said to be 16 percent.6 That same year, the US Centers for Disease Control (CDC) estimated that 1.6 million elementary school children in the US had ADHD, a rate of only seven percent (www.cdc.gov/nchs).

The increase is probably due to changes in diagnostic emphasis. The diagnosis has been broadened to include adults as well as children and patients whose sole complaint is inattention and distractibility at school or work. The diagnosis is certainly in vogue. There have been a rash of popular books on the subject, and several companies are marketing new drugs for ADHD or new formulations of old drugs. Special services, including extra time on standardized tests, are afforded to children and adolescents diagnosed with ADHD. This sort of thing increases the likelihood of an ADHD diagnosis.

It is appropriate, then, to address the question of ADHD diagnosis with a critical eye.

Go to:

What is ADHD?

That’s easy. ADHD is a psychiatric disorder. Why? Because it resides in the Diagnostic and Statistical Manual of Mental Disorders (DSM). And how do you make the diagnosis? Another easy one—If the patient meets the DSM criteria.

Therein, of course, lies the problem. How do you know that the patient meets the DSM criteria, beyond the patient’s subjective reports or the subjective opinions of the patient’s parents, spouse, teachers, etc.? The DSM criteria are perfectly sound, in the author’s opinion. The problem is, though, that the criteria are based on nothing more than reported symptoms. The various elements that comprise the syndrome—locomotor hyperactivity, impulsive behavior, excitability, emotional immaturity, short attention span, distractibility, and inefficiency at school or work—are seldom, if ever, observed directly, let alone measured, by the diagnosing physician. The criteria are a way to systematize diagnosis, but, by their very nature, they are subjective.

The symptoms of ADHD are very common. In one school survey, for example, no less than half of the boys were rated by their mothers as overactive.7 In the Isle of Wight study, 75 percent of the dull children were rated by teachers as inattentive, but 30 to 50 percent of the brighter children were also so described.8

The clinical presentation of ADHD is variable. Some ADHD kids were hyperactive in utero and some are said to “run since they learned to walk.” Others are not hyperactive or impulsive at all, but only inattentive and distractible. Hyperactive kids may turn into lazy, hypoactive adolescents. Girls with ADHD are often shy and self-effacing. Some ADHD patients are referred by their pre-school teachers. Others are only diagnosed in college or graduate school.

The symptoms are situational. Douglas is credited with the idea that the symptoms of ADHD are evoked only under certain circumstances.9 A deficit in sustained attention, after all, is only meaningful in situations where sustained attention is required. If children who can’t sit still and pay attention were simply excused from going to school—as, indeed, they are in many poor countries—then there won’t be any ADHD children left to disrupt class and bedevil their teachers. On the other hand, if every child’s education were strictly individualized, and if normative expectations were removed from the classroom altogether, then minor deficits in learning style would hardly be important. They would simply be the basis for individualizing the child’s learning experience. Indeed, it is arguable that the increased prevalence of ADHD is the consequence of changes we have made in the classroom environment and the high expectations we have of students to perform —from the first grade through college.

So, for all of these reasons, the DSM criteria for ADHD diagnosis are necessary but not sufficient. They are systematic, but not objective. The problem, though, is not the DSM. The problem is what is ADHD really?

ADHD may be a psychiatric disorder but it is not a mental illness, in the sense that depression and schizophrenia are mental illnesses. It is a constellation of personality traits and cognitive styles that cluster, in pure form, in a relatively small number of people and in various combinations and permutations in large numbers of people. It is typical of a large class of neuropsychiatric conditions that afflict large numbers of people to a mild degree and small numbers of people to a severe degree. It is a mild aberration of the regulatory apparatus of the brain, in particular the complex functional systems that are identified with the corpus striatum and the prefrontal cortex.10 It is a relative weakness in one’s ability to regulate attention, behavior, and emotional responding.11 Like most personality traits, it runs in families and tends to persist over the life span. Like most mild impairments, people for the most part learn to adjust to it. Because the central elements of the disorder are functions that are outer-directed (attention, behavioral, and emotional responding), the difficulties that patients experience are usually in their adaptation to external events. For the same reason, certain environments evoke or aggravate the symptoms and other kinds of environment do not.9,12–14

Because ADHD is a condition that exists in equilibrium with a social and educational milieu, a special responsibility devolves upon the physicians and psychologists who diagnose the disorder. ADHD has a variable threshold of expression: The DSM advises that “there has to be clear evidence of clinically significant impairment in social, academic, or occupational functioning” to warrant the diagnosis (DSM-IV-TR, 2000). The arbiters of where, precisely, that threshold lies are the doctors who make the diagnosis. One expects them to be objective, not relativistic, in exercising that responsibility. ADHD is, after all, a medical diagnosis that commits schools to additional expense, affords citizens special privileges, and releases, into a vulnerable population, yet one more class of drugs with potential for abuse.

Diagnosis is one of the perennial problems of the ADHD “movement;” is it possible to make an objective diagnosis when everything about the disorder seems to be subjective? Psychiatrists are accustomed to making informed judgments about what represents a “clinically significant impairment.” But primary care physicians, to whom increasing numbers of ADHD patients and would-be ADHD patients present, would probably prefer to have a more objective standard. The symptoms of ADHD are non-specific. That is, they may be met, alone or together, with a host of other conditions, including psychotic disorders, mood disorders, anxiety disorders, personality disorders, and developmental disabilities. In fact, the proper diagnosis of ADHD requires the clinician to exclude these other conditions. One is not always able to do that with confidence; physicians who are not trained in child psychiatry often find the task daunting.

Go to:

Recommended Approaches to Diagnosis

This is from the Council on Scientific Affairs, American Medical Association, in 1998: The overall approach to diagnosis may involve (1) a comprehensive interview with the child’s adult caregivers; (2) a mental status examination of the child; (3) a medical examination for general health and neurological status; (4) a cognitive assessment of ability and achievement; (5) use of ADHD-focused parent and teacher rating scales; and (6) school reports and other adjunctive evaluations if necessary (speech, language assessment, etc.).15

The economic impact of applying this method to a disorder that afflicts perhaps five percent of schoolchildren is well worth contemplating. Indeed, “diagnostic complexity” and “time constraints” were among the reasons cited by general practitioners for their “low level of interest” in ADHD management.16 The American Academy of Pediatrics suggests a less ambitious, but more realistic approach: Rating scales from parents and teachers, exclusion of alternative diagnoses, and developmental testing, if necessary. Family practitioners are advised to use rating scales, to review the child’s school progress, to screen for vision or hearing impairment and comorbid psychiatric conditions, and to use “objective measures of cognitive function.”17 Child psychiatrists are urged to interview the child and to utilize direct observations (Table 1).18

자료출처 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2993524/