"Unmasking" ADHD in Aging Patients With Comorbidities

Differential diagnosis of attention-deficit/hyperactivity disorder (ADHD) can be difficult for many clinicians as patients age, particularly when other disease states are present, so understanding the nuances of the disorder and how they can change over time is important. 

Vladimir Maletic, MD, MS, clinical professor of psychiatry at the University of South Carolina School of Medicine in Greenville, South Carolina, and Psych Congress Network ADHD section editor, previews his Psych Congress 2023 session "Debate: Is It ADHD or Something Else? Understanding Nuances of the Differential Diagnosis," where attendees can learn about diagnostic tools and methods used in clinical practice to accurately diagnose ADHD. 

For more news and live coverage from Psych Congress 2023, visit the newsroom.

Read the transcript:

Meagan Thistle, Psych Congress Network: You had discussed screeners and ways that clinicians can better use those screeners to eventually make their diagnosis. Why, though, is ADHD sometimes still missed in patients who are maybe in that transitional life period? How does ADHD look a little bit different in that population?

Dr Vladimir Maletic: Meagan, that's a very, very interesting question because something that we do know about ADHD is that stress and structure have a major role in how ADHD is expressed. The other part that is relatively novel, Meg Siblian and her colleagues have published an interesting study looking at what happens with ADHD once one crosses that boundary of 18 years old. In the past, the assumption was that roughly two-thirds, so 65 to 70% of the child and adolescent population, will retain their symptoms into adulthood. Her research is longitudinal and comes up with some very interesting conclusions.

In terms of crossing that threshold into adulthood, 10% of individuals previously diagnosed with ADHD will have an ADHD diagnosis at all points of time when they were being assessed. On the other hand, 10% of the patients will not have a diagnosis at all points of time when they were being assessed. About 10% of the individuals who had ADHD symptoms as a child will cease to have those symptoms. On the other hand, I'm rounding these numbers off, they're actually a little bit different, 10% will continuously meet the diagnosis.

Well, what happens with the remaining 80%? What happens with the remaining 80% is they have fluctuation of symptoms. In certain settings, those symptoms may be more pronounced. In certain life situations, they may be more pronounced and, in other settings, not so. When it comes to the phase that you are inquiring about what happens when one is leaving high school and home? Well, number 1, there's a bit of oversight on the part of parents. Number 2, life is fairly structured. You get up at a certain time, you get ready, you go to classes, you're getting fairly rapid feedback in terms of oral presentations, written tests. You have a pretty good idea of how you're doing. Yes, there are some temptations in teenage lives. But what happens when one goes to college, parental oversight is gone, most often. Structure is gone and one does not get regular feedback, and there are way more temptations than in the past.

In other words, ADHD that may have been relatively well compensated up to that point, with these guardrails and supportive aspects in one's life removed, all of a sudden in many individuals, the wheels may come off and there may be greater impairment in functioning. Now, this is not a rule because there are individuals who have ADHD who will be aware of their symptoms and the impact on functioning and will go through extra effort in order to remain focused. Another thing that may influence it, frankly, a degree of diversion of the medicines in those teenage years is the greatest. About 10% of individuals who receive a stimulant prescription will either misuse them or they will be shared with friends. Obviously, that will be problematic and it leads to important changes in their functioning. So to say.

Something else to keep in mind, if they have not been treated or appropriately treated, they may not have had the diagnosis up to that point. They were able to compensate, especially intelligent females. They were very likely to compensate and not even be diagnosed. In this change of setting, now the symptoms may become more prominent.

The other thing to keep in mind, if ADHD is not treated, it does influence how the diagnosis is made. Here is what I mean. ADHD is highly comorbid. It is highly comorbid with anxiety disorders. It is highly comorbid with mood disorders. I'm talking about MDD and bipolar disorder. It is highly comorbid with substance use disorders. Many times, when the diagnosis is made later on, it is not a diagnosis of ADHD, it is a diagnosis of comorbidity. ADHD continues to be masked.

There was some suggestion from this, even a national comorbidity survey. Kessler and colleagues published this in 2006, and what they found is that an extraordinarily low percentage of individuals in the national comorbidity survey, I think it's about 10%, were receiving some form of treatment in the past 12 months. They're being seen, but they're not treated for ADHD. They are being treated for anxiety disorders. They're being treated for mood disorders. They're being treated for substance use. This is where screening is really important in this teenage population that is going through this transition. They're doing worse. I'm not saying don't treat their anxiety, substance use, or mood disorder. I'm saying, especially if they're not responding the way we hope, keep it in the back of your mind that they actually may have ADHD and pay attention and try to gather the evidence that would support comorbid ADHD. Because if left untreated, it is extremely detrimental.

We know that when it comes to comorbidity between ADHD, substance use disorders, and mood disorders, this comorbidity increases with age. Leaving ADHD untreated may be one of the reasons why they may be suffering more from anxiety disorder, substance use, and mood disorder. Definitely, more careful screening and, again, being aware of circumstances.

Thistle: Thank you for sharing that. You give clinicians a point to recognize, "Okay, my patient might not be responding to treatment for XYZ disorder. Maybe it's time we screen now for ADHD." I think that's a really good clinical pearl that folks can bring back into their practice.

We are coming up on time, Dr Maletic. I have 1 final question for you. What further research do you feel is needed in this area and are there any key highlights that you'd like to share with our audience of Psych Congress Network before we end our conversation?

Dr Maletic: Yes. We do need better studies. The approaches that have been pretty effective in the past in the child and adolescent population is to look at the studies. Now, in these large-scale studies, the way it is conducted now, it's usually an email with a questionnaire. Studies in child and adolescent populations that have parental components and teacher components are very helpful. There is some indication that if parents either believe their child has ADHD or report their child being diagnosed by somebody with ADHD, there's about 90% accuracy compared to the full clinical interview. Parental information, teacher information, age of onset that has been established and, in addition to that, then sub-sampling. Sub-samples of that large population are then having the full clinical interview in order to assess ADHD and looking at concordance rates. That would be something that would be very important.
In terms of adult ADHD, I would advise a similar approach with one modification. We can't always get external confirmation of the diagnosis, be it through medical records, especially in these large-scale studies. But if there is a structured clinical interview, I would advise that sub-sample of those individuals also have direct contact with the clinician to see if the diagnosis holds or not.

Lastly, if there is a claim the diagnosis was present before age, in the past 7, now 12, let's have some confirmation. Let's have some school records. Let's have some clinical notes to indeed confirm that this diagnosis was made in the past. The reason for that is, whether we like it or not, due to the COVID-19 pandemic, a lot of the clinical work has shifted into the virtual domain and telepsychiatry domain. We don't have all the elements to make the diagnosis that we have had in the past. Frankly, there has been more temptation in individuals who don't have ADHD to simulate having ADHD symptomatology in order to obtain stimulants. That is becoming a public health problem. We don't want to be willy-nilly with our stimulant prescriptions but, on the other hand, we don't want to sacrifice the benefits of being able to contact and screen a larger number of patients who potentially do have ADHD. We have to balance it. We don't want to be over-diagnosing and over-prescribing but, on the other hand, we don't want to discard the benefits of new technology and expanded access.

Those are some of the things to keep in mind. Again, we may not be able to confirm clinically for everybody, but at least having sub-samples where we have a thorough clinical interview confirming the diagnosis and that will give us an idea how much we are on target or how much we are off target.

Thistle: Right. Thank you, Dr Maletic, for exploring this topic of is ADHD under or over-diagnosed with me today. It's always a joy to talk to you. I would like to invite all viewers here today to go back and check out our ADHD excellence form as well as our topic center for ongoing news and insights on the topic. Thank you again, Dr Maletic.

Dr Maletic: Thank you very much, Meagan. I also wish to thank all our audience members for joining us for this conversation. Thank you.

Vladimir Maletic, MD, MS, is a clinical professor of psychiatry and behavioral science at the University of South Carolina School of Medicine in Greenville, and a consulting associate in the Division of Child and Adolescent Psychiatry, Department of Psychiatry, at Duke University in Durham, North Carolina. Dr Maletic received his medical degree in 1981 and his master’s degree in neurobiology in 1985, both from the University of Belgrade in Yugoslavia. He went on to complete a residency in psychiatry at the Medical College of Wisconsin in Milwaukee, followed by a residency in child and adolescent psychiatry at Duke University.