The diagnosis of ADD is typically made when a person has marked inattention, or distractibility, along with “executive dysfunction”, or disorganization. In adults, there is usually not an inability to sit still in classrooms (mistakenly labeled “hyperactivity”) since most adults are no longer in school; rather the executive dysfunction is typically the primary complaint.
An initial observation is that it is clearly false to assume that ADD persists into adulthood. This assumption is based on restrospective studies that are of worse quality than prospective studies which find the reverse. The rise in diagnosis of adult ADHD fully coincides with marketing by the pharmaceutical industry, when Eli Lilly got the first FDA indication for this label with atomoxetine (Strattera) in 1996. Since that date many academics, often paid by the pharmaceutical industry, have been promoting the concept of adult ADHD. This is a good example of “disease-mongering”, when a condition that has never been observed in centuries of medical research by very competent experts is suddenly made popular in association with a new treatment being offered for it, and profits to the companies that market that new treatment.
The retrospective studies that most clinicians hear about cite that about 50-60% of childhood ADD persists into adulthood. These data are disproven by prospective studies, which repeatedly show that about 80% of children with ADD do not continue to have that diagnosable condition, followed prospectively either into young adulthood or even for 33 years into their fourth decade of life. 20% persist, 80% do not. A minority persist; most children with ADD do not continue to meet criteria for the diagnosis into adulthood. Further, these prospective studies have control groups, i.e., children who do not have ADD. This is not a matter of misdiagnosis or not receiving clinical attention; these children are enrolled in a prospective study and determine to have or not have ADD. Among the adults diagnosed with ADD, 80% of them did NOT have ADD as children, again diagnosed prospectively, not retrospectively. Since adult ADD is defined as the persistence of childhood ADD, then these individuals did not have adult ADD, even though they met adult criteria for it, since they did not have it as children.
So most children with ADD – 80% – will not persist into adulthood. And most apparent adult ADD is not ADD, since it did not exist in childhood.
These prospective data throw the legitimacy of the diagnosis into question. A possible explanation, ignored by the DSM system, relates to the concept of a diagnostic hierarchy. In other words, plenty of otehr diagnoses exist which can cause ADD-like symptoms, and in current practice, those persons are misdiagnosed as having adult ADD.
In the National Comorbidity Study (NCS), an epidemiological analysis of prevalence of all mental conditions in the US, 3% of the US population was diagnosable with adult ADHD (meaning meeting standard criteria as adults and, retrospectively, in childhood). Of these patients, over 40% also were diagnosable with bipolar illness, and over 40% were diagnosable with “major depressive disorder” (MDD). In sum, 84% were diagnosable with mood illnesses. Using the concept of a diagnostic hierarchy, described here, poor attention is a symptom of depression and mania (and anxiety); thus the occurrence of inattention while a patient has depressive or manic symptoms or episodes does not mean that the person has both an attention “disorder” and a mood “disorder”. This would be like saying every person with pneumonia also has a fever “disorder.” It is common to find that someone who thinks they have adult ADHD actually have other illnesses, mood and anxiety conditions, which cause the symptom of inattention. This has also been shown in a 33 year prospective follow up study of children with ADHD into adulthood, and in another NCS analysis which found that the inattention of adult ADHD subjects occurred only with concurrent anxiety disorders.
Another important and large group is ignored in these studies: mood temperaments. Many clinicians mistakenly do not make mood illness diagnoses based on the view that mood conditions are episodic, while ADD is chronic and constant. If someone has attentional impairment or executive dysfunction all the time, then it can’t be a mood illness, clinicians think, since mood states come and go; they are episodic; ADD is not. But mood temperaments do not come and go; they are present all the time, as part of one’s personality. Conditions like cyclothymia, hyperthymia, and dysthymia involve constant presence of mild manic and/or depressive symptoms. Since these manic and/or depressive symptoms are present all the time, they certainly can produce inattention and poor concentration and poor executive function all the time. There are few studies on this topic, though an association between undiagnosed cyclothymia and ADD diagnoses has been identified. In a study in press, our group recently assessed this matter in our mood clinic, and we found that mood temperaments were present and diagnosable in the majority of patients who came to our clinic diagnosed with adult ADD in the past or treated with amphetamines.
There are two possible explanations of the fact that “adult ADHD” frequenly happens with mood and anxiety conditions in adults. Either the mood and anxiety conditions cause the poor concentration, which is our view, or the adult ADHD causes the mood and anxiety symptoms, which is view of those who prefer to diagnose adult ADHD. In the latter case, the claim would be that every time someone has adult ADHD, they get very depressed and anxious about having adult ADHD. This may be plausible colloquially, but there is no scientific research to support it. On the other hand, there are about two centuries of research studies that state that depressive, manic, and anxiety conditions cause poor concentration, and that the inattention of those states improves once the mood and anxiety conditions improve.
Based on these considerations, our view is that the diagnosis of adult ADHD is not a scientifically valid condition. It is not an illness or disease. Children may be diagnosable with ADHD, but their symptoms are either due to mood or anxiety illnesses , or due to a developmental delay in attention which normalizes by adolescence in most cases and certainly by adulthood.
We do not recommend making the diagnosis of adult ADHD, given the considerations about its scientific invalidity here. Treatment with amphetamines is also not recommended since the diagnosis is questionably valid. Risks with amphetamines, including sudden death in adults, make such treatment even more questionable, and are discussed in more detail here.