I have found this to be a difficult question to answer, primarily because I am asked it most often by people who are unconvinced by anything a psychiatrist has to say on the topic. What does “real” mean as it pertains to psychiatric difficulties? Psychiatry is a relatively new field and accurate diagnostic categorization is very much an area in development. The diagnostic tools that are available to other medical specialties, such as blood tests or imaging data (e.g. x-ray and MRI) are not useful in psychiatric disorders.
In medical terminology, ADHD is a syndrome. This means that it describes a specific constellation of symptoms that are often found together in the same individual. It does not mean that there is an identified underlying biologic etiology. Impaired attention can be caused by numerous different neurochemical dysfunctions; it is quite possible that two people with very different underlying neuropathology (often colloquially referred to as a “chemical imbalance”) can present with the same outward symptoms of attentional problems.
What we do have are solid data that certain patterns of hyperactivity, inattention and disorganization can be attributed to genetic heritability, and that these symptoms cause consistent life challenges. We also know that these symptoms can improve with specific medications and psychotherapeutic treatments.
The Diagnostic and Statistical Manual of Mental Disorders (DSM) is the psychiatric guidebook for diagnosis. It is not the final word on mental illness for all time, but it is helpful as a description of what is currently known about common psychiatric syndromes. It is not intended to pathologize the human condition. Using ADHD as an example: if ADHD is in the DSM, this does not mean that there is – or is not – something “wrong” with people who have ADHD, nor does it take sides in the issue of whether a person with ADHD would be impaired in any time and place or whether instead current educational and occupational environments reward only a narrow set of cognitive strengths. And it does not mean that patients who can be diagnosed with ADHD must receive any particular treatment. The DSM is helpful because patients with the symptoms of ADHD often come to psychiatrists reporting that they are experiencing emotional distress and occupational challenges, and they want to know what might be done to improve their situation. The psychiatrist needs to be familiar with the medical literature to give an answer as to what might help. Sometimes the answer might be medication or therapy, and sometimes it might be to change jobs, relationships or habits. But without agreed upon definitions, there would be no research to help provide that answer. It is only by studying defined syndromes – however incomplete or impartial our understanding – that we can give meaningful answers regarding what is currently understood a about the prognosis and treatment options for symptoms that are causing distress.
We know that the current diagnosis for ADHD captures a very heterogeneous group of patients with very different underlying brain structure and life problems (this is particularly true for Inattentive ADHD). Ongoing research will eventually bring greater specificity to our understanding of the genes, environmental stressors and brain regions involved in ADHD, but for now, we have to start somewhere.
So is ADHD real? It is a name given to specific set of problems that some people undeniably experience, and it is a diagnosis intended to be used only for people who experience these problems far more than the average person. But given the uncertainty around the specific causality of these problems for any particular person, combined with the current methods of psychiatric diagnoses, it is probably not accurate to say that a person has trouble paying attention because they have ADHD, but rather: we call it ADHD if they have trouble paying attention.
It is estimated, using current psychiatric diagnostic categorization, that approximately 4% of the adult population meets criteria for ADHD. For those who remain unconvinced by the data, there is this: If you take 25 adults and rank them for difficulties with attention, organization, restlessness and impulsivity, one of them will be the worst. Call it whatever you like. Are we going to just pass judgment on that person and watch them struggle, or if they are seeking help, will we see if something might be done to improve their situation?