What Is ADHD, and How Do Doctors Diagnose it?

In honor of ADHD Awareness Month, we’re pleased to share this blog post from pediatrician Dr. Arthur Lavin. You can get more trusted health information from Dr. Lavin on the ParentTalk Podcast!

There are very few families that do not have a child suspected of or diagnosed with ADHD or that know of a family with such children. ADHD is talked about across the nation and appears in magazines, news stories and medical journals with high frequency. 

We have come to a place where ADHD is one of the first considerations when any child struggles in school. So it makes sense to take a step back and ask: what is ADHD, and how do we know who really has it? Let’s discuss.

Attention-deficit/hyperactivity disorder (ADHD) is a collection of symptoms that define the syndrome. It is not a disease that can be diagnosed with an objective test, such as a blood test, DNA analysis or an MRI. 

Unlike strep, for example, which is an infection defined by its presence in a throat culture, or high blood pressure, a condition that’s defined by measuring blood pressure, ADHD is a syndrome. This means that there are no measures for it, just set characteristics, symptoms or behaviors that are not caused by something else.

We need two items to be confident that someone has, or just as importantly, does not have ADHD:

• The list of ADHD symptoms
• The list of other causes for those same symptoms

Around the world, the source that defines ADHD is the Diagnostic and Statistical Manual of Mental Disorders (DSM-V). This reference book outlines nine symptoms under the category of inattention and nine symptoms under the category of hyperactivity-impulsivity. For a child up to the age of 16 to be considered to have ADHD, they must have six of the symptoms in the inattention list OR the hyperactivity-list (or five symptoms past the age of 16). If they don’t, they don’t have ADHD. You can find the full list of symptoms on the CDC website.  

But having the symptoms is just the start. Your child can have all the symptoms and not have ADHD. To be diagnosed with ADHD properly, the following conditions must also be met:

• Symptoms began prior to age 12
• They occur in more than one place (so not only home or only school)
• The troubles must be impairing (i.e., must cause difficulty)
• The symptoms cannot be caused by a better explanation

This last point cannot be stressed enough. Across nearly four decades of pediatric practice, I have personally seen so many children diagnosed with ADHD by qualified mental health professionals – kids who did not have it. They had the symptoms, but on a closer look, we fairly easily found other causes that explained the symptoms far better.  

This experience is so widespread that the American Academy of Pediatrics published a policy paper that lists 49 other conditions that can look just like ADHD and are mistaken for it. Examples include anxiety disorder, dyslexia and other cognitive impairments. Each of these in 49 conditions can cause all the symptoms on the ADHD list. 

There is work being done to try to create objective measures that can tell you, with one quick test, if someone has ADHD. However, the science is very far from this reality, despite many products claiming to have solved this challenge. Currently, only a careful evaluation that really looks at the child at hand and truly considers all the possible causes can find the true cause(s) for the symptoms a child has. This almost always requires the help of a skilled psychologist and/or a pediatric neuropsychologist.  

This question is difficult to answer since ADHD is a syndrome, not a defined physical reality.  But some patterns give us hints that there may be physical realities underlying the symptoms of ADHD. For example:

The tilt towards boys is not as dramatic as we once thought. We’ve seen that many females (or individuals assigned female at birth) with ADHD just hide their symptoms better, but even so boys (or individuals assigned male at birth) are clearly more likely to have ADHD. No one knows why, and so theories abound. Could it be the testosterone, pushing boys to be more active? Is it a cultural influence? Do male minds process information differently than female minds? Is there a gene that’s more common in boys? At this time, we don’t know these answers, only that boys are more likely to develop ADHD than girls.

The first modern descriptions of ADHD occurred in France in the late 19th century when a scientist observed that kids who had suffered head trauma from horses and carts showed a pattern of inattention and hyperactivity. It was originally termed MBD, or moderate (after a time mild) brain damage. Ever since, scientists have looked for evidence of damage or differences in the brain tissue of children with ADHD, with mixed results. But the pattern of traumatic brain injury associated with symptoms of ADHD persists.

Another form of injury now proven to cause ADHD is the harm caused by chemicals known to damage brain development and function. These neurotoxicants include the familiar lead poisoning, but also a set of pesticides called organo-phosphate pesticides. Not that long ago, it was found that the higher the concentration of such pesticides in the urine, the more likely the child would have ADHD. Other chemicals known to play a role in ADHD include polybrominated diphenyl ether (PBDE) flame retardants, phthalates, mercury, air pollution and others as well. 

Parents, be aware that some of these, like flame retardants and phthalates, are found in conventional crib and kids mattresses, where your child certainly spends a lot of time. Read my advice on Keeping Baby Safe from Toxic Chemicals here.

In the vast majority of ADHD situations, the issues for children begin with school. Families of course observe behaviors that include inattention, impulsivity and/or hyperactivity. And, it should be noted these symptoms are extremely common; nearly all of us at any age have moments that include such symptoms. But the question is: do these behaviors rise up to the level of concern? That determination is often first made by a teacher.

If you or your child’s teacher are concerned, it’s important to do all you can to be sure you find out the real answer to two key questions:

Are these symptoms of concern or a normal variation of childhood?
If they are of concern, what is their cause?

The most common tools of most pediatricians, psychologists, psychiatrists and other professionals are questionnaires that ask which symptoms are present and how often they appear. These tools do a good job of measuring how severe the symptoms are, but they are incapable of determining why they occur.  

So, first find out the severity, and most professionals can help with that. But then, to find the cause(s), you need to be very open with the professionals you turn to for help and make sure you advocate for looking beyond ADHD as an explanation and considering the whole picture – and not just stopping with ADHD as the only possible cause.

If a reliable look at causes is conducted and ADHD emerges as the best explanation, then it makes sense to embark on possible therapies for that syndrome.

• ADHD is the dominant explanation for troubles in school that feature inattention, but there are dozens of conditions that can cause every symptom of ADHD.
• ADHD is not a disease defined by objective measures. It’s a syndrome constructed around a set of 18 symptoms, nine related to inattention, nine related to hyperactivity/impulsivity.  
• An ADHD diagnosis requires both a number of symptoms present and key features such as age of onset, but also that other conditions or diagnoses aren’t the cause.
• For most children with ADHD, the cause is unknown. However, two known causes of ADHD symptoms include traumatic injury to the brain and exposure to toxins that harm brain development.
• If you suspect ADHD, questionnaires help to determine what is causing your child’s symptoms but your child will need a more in-depth evaluation.
• Putting it all together, it is a worthy effort to protect our children from risky activities that cause physical bangs to the head and from exposures to known neurotoxicants. When symptoms of ADHD appear and professionals like teachers suggest they are severe enough to justify evaluation, be sure to stay committed to finding the cause.

To learn more about the connection between chemical flame retardants and ADHD, read Dr. Lavin’s blog post: Are Chemical Flame Retardants Safe? A Pediatrician Breaks it Down! You can also learn more about ADHD Awareness Month and how to get involved here.