“There is no increase in ADHD or autism in the population,” says first Brazilian to receive the ‘mental health Oscar’

(Interview originally published by O Globo after Rohde, scientific supervisor at the Stavros Niarchos Foundation (SNF) Global Center for Child and Adolescent Mental Health at the Child Mind Institute in Brazil, received the Outstanding Achievement Prize—a kind of mental health Oscar—for his lifetime contribution to developmental psychiatry, with a primary focus on ADHD)

Luis Augusto Rohde is a professor at the Federal University of Rio Grande do Sul (UFRGS), where he directs the Attention-Deficit/Hyperactivity Disorder Program at the Hospital de Clínicas, and serves as vice coordinator of the Center for Research and Innovation in Mental Health (CISM). He has also led the World Federation of ADHD and is currently president of the International Association for Child and Adolescent Psychiatry and Allied Professions (IACAPAP).

Speaking to O Globo, the psychiatrist addresses whether we are in fact seeing an increase in ADHD — the disorder to which he has devoted his career—discusses the rise in formal autism diagnoses, warns about the risks of misinformation on social media, and explains what should serve as warning signs for parents of children and adolescents.

The award recognizes your career, especially your research on attention-deficit/hyperactivity disorder (ADHD), which strongly focuses on diagnostic epidemiology. Are we experiencing an increase in cases?

When we look at the frequency of ADHD in the population and control for methodological aspects of studies, there is no difference in prevalence across countries. We analyzed more than 102 studies worldwide and found that the disorder affects about 5 percent of children and adolescents. We then examined changes over the past 30 years and clearly saw that, once methodological issues are again adjusted for, there has been no increase in what we call population prevalence.

However, when we look at administrative prevalence—that is, demand for health services—we do see an increase in many parts of the world. Why is that? Because there is greater awareness of the diagnosis, and we have begun to better recognize ADHD in girls and in adults. Until recently, the disorder was seen as something restricted to males, because it was strongly associated only with hyperactivity. But there is also a presentation with predominantly inattentive symptoms, which is more common in girls and was not recognized by schools.

And what about autism spectrum disorder (ASD)?

The issue is a bit more complex. If we looked at any child and adolescent mental health textbook 20 years ago, it would state that prevalence was between one and four cases per 10,000 births. In the most recent survey by the U.S. Centers for Disease Control and Prevention (CDC), that figure reached one in 36 births. But we also have not seen an actual increase in autism in the population over those 20 years.

What has happened is that we no longer work with that very narrow view that considered only the absence of verbal communication. We expanded the concept to a spectrum, with more flexible diagnostic criteria. As a result, things that were previously called “autistic traits” or simply personal characteristics are now understood as part of ASD. This broad flexibility in what constitutes a diagnosis has led to an increase in prevalence.

"It is natural to seek information on social media, but the quality is often not scientifically sound"

- Luis Augusto Rohde, professor at the Federal University of Rio Grande do Sul and scientific supervisor at SNF Global Center

Today, many people look for simple explanations for the causes of autism or other psychiatric diagnoses. How do you see this scenario?

It is human nature to seek explanations for certain phenomena. But the caution we need to have is in distinguishing between association and cause-and-effect relationships. There is, for example, widespread concern about whether excessive screen time leads children to develop more ADHD, and studies do show a very clear association between the two. However, we followed 2,500 people in a cohort study in São Paulo and Porto Alegre since childhood and found that the direction appears to be the opposite.

In fact, individuals with more ADHD symptoms tend to use screens more. Sometimes this is because ADHD has a genetic component, meaning these individuals often have parents who are also more impulsive, with fewer routines—behaviors that facilitate greater screen use by their children. So, there are associated factors, but the relationship is not always causal, and sometimes it is reversed.

And what about misinformation on social media?

A very interesting study evaluated the 100 most-viewed ADHD-related videos on TikTok, which together, accounted for half a billion views. Experts in the field assessed the quality of the information presented. The question was: do the symptoms or characteristics being described as ADHD actually correspond to ADHD? More than 50 percent of the supposed manifestations described in those videos did not correspond to the disorder.

This is a major problem today. It is natural for people to seek information on social media, but the quality of that information is often not scientifically sound. There is growing concern about improving the quality of what is shared. At IACAPAP, we have been developing work in partnership with the Child Mind Institute (CMI) in New York to train influencers on child and adolescent mental health topics.

What do we know today about ADHD?

We know it is a neurodevelopmental condition—that is, related to the maturation of certain brain areas—which leads to symptoms of inattention, hyperactivity, and impulsivity. It mainly involves a region at the front of the brain called the prefrontal cortex, which is responsible for inhibitory control. If this region is more immature, the person becomes more agitated and impulsive. This also affects attention because, to focus on something, we need to filter out background noise, emerging thoughts, and dozens of stimuli that must be inhibited.

These alterations have a strong genetic component. When we begin evaluating a child, it is common for parents to say, “What you’re describing, I was like that too as a child,” or “I’m like that myself.” So we see family history, and twin studies show that transmission occurs largely through genetics.

However, ADHD is not a categorical diagnosis in medicine, like an infection, where you either have it or you don’t. Attentional capacity, inhibitory control, impulsivity, and hyperactivity are traits distributed dimensionally across the population, like height, which varies from shorter to taller individuals. We need to be very careful, because in stressful situations, when demands increase, it is natural for people to become more hyperactive or inattentive.

What should alert parents?

Parents should pay attention when symptoms of inattention, hyperactivity, and impulsivity occur in a marked and frequent way and cause functional impairment—whether in learning, peer relationships, or family interactions. The warning sign is high frequency of symptoms combined with associated functional impairment.

When is aggressiveness a normal part of development, like a typical tantrum, and when can it be a warning sign?

Anger and aggressiveness are part of development. A child being able to express these emotions in appropriate ways, such as through sports or other outlets, is extremely important. We start to worry when these behaviors become frequent. Instead of a tantrum once every 15 or 20 days, there is a pattern of two or three times a week. The intensity and duration—for example, when episodes last more than half an hour—are also important factors to assess, along with how much this behavior affects the child and family life. This may reflect family dysfunction, but it may also be related to the child’s biological characteristics.

Are other psychiatric diagnoses categorical?

No. We have none with a biological marker. All of them—such as autism, depression, and anxiety—are clinical diagnoses. Today, we understand them within this dimensional framework, which is why we need to evaluate frequency and associated impairment. Anxiety and depression are widely discussed, and there are even groups advocating for screening children for these disorders.

What is the impact of these diagnoses among young people?

A study I participated in evaluated the prevalence of mental disorders in children and adolescents and, more importantly, the disease burden—the years lived with the condition combined with increased mortality. We clearly see that, among young people aged five to 24, mental disorders account for the greatest disease burden. And among them, anxiety and depression stand out. That is why we have emphasized programs focused on recognition and intervention targeting these two conditions.

What do we know today about the best forms of treatment?

In mental health, it is important to always think in terms of multimodal treatment. This means combining evidence-based psychotherapeutic interventions with psychoeducation and, when necessary, the use of medication. Psychoeducation is crucial because we need to remove stigma surrounding mental disorders. Many children with ADHD are labeled as poorly behaved or lazy, which is not true. We also need to remain open to new evidence. Today, the scientific literature clearly shows the importance of aerobic physical exercise for improving executive function and attention, as well as for reducing depression in children and adolescents.