I suggest you do some reading about how his words were translated, and what the context of the Der Spiegel article is. Were you to actually educate yourself about that, you'd realize that he is arguing that ADHD is over diagnosed, which is certainly the case and something already addressed in this thread numerous times.
http://www.snopes.com/politics/quotes/adhd.aspThe claim that Dr. Eisenberg asserted "ADHD is a fictitious disease" is reproduced on countless web sites as something he said "seven months before his death in his last interview," which would place the date of his utterance around February 2009. When documentation for the putative quote is provided, it references an article (often described as a "cover story") published in the German weekly Der Spiegel on 2 February 2012.
We found that the German-language version of Der Spiegel ran an article in 2012 that skeptically examined the large increase in diagnoses of mental disorders in recent years and quoted Dr. Eisenberg on that subject. A software-based translation of that article from German to English does describe Dr. Eisenberg as the "father of ADHD" and report that during his "last interview" he said something similar to "ADHD is a prime example of a fictitious disease." However, allowing for the vagaries of translation and reading the statement in context, some native German speakers have reported that Dr. Eisenberg wasn't asserting that ADHD isn't a real disorder, but rather that it is overdiagnosed:
One out of every ten 10-year-old boys already takes an ADHD drug daily. But the scientific father of ADHD has followed the explosion of prescriptions with growing horror. Leon Eisenberg took over the management of psychiatry at the prestigious Massachusetts General Hospital in Boston and became one of the most famous psychiatrists in the world. In his last interview, seven months before his death from prostate cancer at the age of 87, he distanced himself from his youthful indiscretion.
A tall, thin man with glasses and suspenders opened the door to his apartment in Harvard Square in 2009, invited me to the kitchen table, and poured coffee. He said that he never would have thought his discovery would someday become so popular. "ADHD is a prime example of a fabricated disorder," Eisenberg said. "The genetic predisposition to ADHD is completely overrated."
Instead, child psychiatrists should more thoroughly determine the psychosocial reasons that can lead to behavioral problems, Eisenberg said. Are there fights with parents, are there are problems in the family? Such questions are important, but they take a lot of time, Eisenberg said, adding with a sigh: "Prescribe a pill for it very quickly."
On a related note, an August 2012 Der Spiegel English-language interview with (now retired) Harvard psychologist Dr. Jerome Kagan quoted Dr. Kagan as being critical of "fuzzy diagnostic practices" and the over-prescription of drugs such as Ritalin for behavioral problems in children, and as referring to ADHD as "an invention":
SPIEGEL: In the 1960s, mental disorders were virtually unknown among children. Today, official sources claim that one child in eight in the United States is mentally ill.
Kagan: That's true, but it is primarily due to fuzzy diagnostic practices. Let's go back 50 years. We have a 7-year-old child who is bored in school and disrupts classes. Back then, he was called lazy. Today, he is said to suffer from ADHD (Attention Deficit Hyperactivity Disorder). That's why the numbers have soared.
SPIEGEL: Experts speak of 5.4 million American children who display the symptoms typical of ADHD. Are you saying that this mental disorder is just an invention?
Kagan: That's correct; it is an invention. Every child who's not doing well in school is sent to see a pediatrician, and the pediatrician says: "It's ADHD; here's Ritalin." In fact, 90 percent of these 5.4 million kids don't have an abnormal dopamine metabolism. The problem is, if a drug is available to doctors, they'll make the corresponding diagnosis.
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So once again, we see that ADHD is over-diagnosed, is very related to issues of parenting, diet, etc., but nonetheless exists for roughly 1-2% of the population. I mean there are piles of literature talking about brain differences between those actually tested and diagnosed with ADHD and those who exhibit normal behavior. It may certainly be fictitious for the majority of those medicated for it, but it absolutely is not for those actually afflicted with it.