ADHD: why are clinic referrals on the rise?

Attention deficit hyperactivity disorder (ADHD) is a diagnosis given to people who have challenges with inattention, hyperactivity, and/or impulsivity.

According to the Royal College of Psychiatrists, ADHD affects about three to four in every 100 adults. ADHD is more commonly diagnosed in boys than in girls. However, in adults the diagnosis of ADHD in men and women is more equal. This might be because, as children, boys are more likely to show hyperactive and impulsive symptoms, which are more noticeable.

The past couple of decades have seen a continuous increase in diagnoses and prescriptions for ADHD medication and a recent investigation revealed that children with suspected ADHD and autism are waiting up to seven years for neurodevelopmental appointments.

A recent British Medical Journal (BMJ) webinar reviewed the diagnosis, treatment, and support of people with ADHD to shed light on some common misconceptions about the condition and look at why clinic referrals are growing.

What is ADHD?

Anita Thapar, Professor of Child and Adolescent Psychiatry at Cardiff University, began the session by looking at how ADHD is defined. She said that in clinical settings, two main diagnostic classification systems are used. One is the International Classification of Diseases 11th Revision (ICD 11) and the other is the Diagnostic and Statistical Manual of Mental Disorders Fifth Edition (DSM 5).

Both are broadly similar in their definitions to reach a diagnosis of ADHD. Patients need multiple symptoms of impulsiveness, hyperactivity, and inattention. The current classification system also requires that problems start before the age of 12. It is also not enough to have symptoms in one setting, such as at home. These symptoms would also have to interfere with day-to-day functioning. For children, this could be building peer and social relationships. For adults, that could mean managing day-to-day tasks.

ADHD is currently grouped as a neurodevelopmental disorder with onset in early development along with conditions such as autism, dyslexia, and learning disability. All these conditions show massive overlap and ADHD also has a higher-than-expected risk of epilepsy.

She added that a lot of people think ADHD is new and mostly a Western problem. Instead, it has been described for centuries in the medical literature, with the current classification systems arriving in the mid to late 20th century to create the current concept of ADHD. Also, there has been no change in symptom levels across the decades.

Multiple studies also show no clear cut differences in regard to prevalence across various countries, even when you look at non-European countries.

So why have clinic referrals increased? One possibility, she said, is over-diagnosis, yet there is no evidence of this for ADHD. Instead, the reason could be increased recognition of ADHD, especially in the adult and female population. Also, research shows that although symptoms haven’t increased, the recorded impact of the same symptoms on families is greater than it was 30 years ago, which would drive referrals.

Professor Thapar then went on speak about the causes of ADHD. She said that there has been a lot of speculation about this, but actually the genetic research is really robust across multiple different countries. ADHD runs in families and there is a really strong genetic influence on ADHD, like autism and schizophrenia.

To conclude, she said ADHD is well recognised, well researched, and requires a careful assessment. This is not just because it is a continuum, but because healthcare professionals have to balance risks versus benefits of medication. There are also multiple ADHD adverse impacts and costs so it is not something to be ignored. Finally, she added that physicians needed to be wary about what they read as there are many misrepresentations about the condition that are not grounded in research.

Evidence for drug treatment

Dr Daniel Gorman, Director of Postgraduate Education at The Hospital for Sick Children, Toronto, spoke about pharmacological management of ADHD and the increased uncertainty about who should be treated.

He said it is quite clear that ADHD medication, especially stimulants, improves inattention, hyperactivity and impulsivity in the short term. In fact, he said, it was one of the gratifying aspects of his work seeing children improve very rapidly before his eyes. But the question of what the long-term benefits and harms of medication are remains important. Unfortunately, there is very little robust research to inform us.

He said that the prevalence of ADHD prescriptions varies widely across the globe, but it is highest in the US. Most countries, however, are seeing increasing rates of ADHD prescriptions over time, with some researchers suggesting that the prevalence of ADHD might be as high as 7% of the population.

He said lots of factors have impacted on this increased prescription number, including the influence of the pharma industry and direct-to-consumer advertising, but the biggest influence has been a study that was published in 1999.

The Multimodal Treatment Study (MTA) study compared two different treatments and their combination for ADHD. One treatment was medication alone, mainly involving stimulants. The second treatment was behavioral treatment alone, very intensively delivered, and the third arm was combined treatment.

The group of 579 children, aged 7 to 9.9 years, were assigned to 14 months of medication management (titration followed by monthly visits); intensive behavioral treatment (parent, school, and child components, with therapist involvement gradually reduced over time); the two combined; or standard community care (treatments by community providers).

Dr Gorman said that the headline from this study was that medication is best and intensive behavioral treatment doesn’t actually add very much to medication alone, at least for the core ADHD symptoms of inattention, hyperactivity, impulsivity.

Yet, it also found that the combined treatment may have provided modest advantages for non-ADHD symptoms and positive functioning outcomes. This included symptoms such as anxiety, academic difficulties, oppositional behavior, social problems, and parent-child relationships – symptoms that are often the real driver for why families present to clinics. So, clinically, combined treatment was actually best.

Benefits and harms of ADHD medication

Dr Gorman then came back to the question of who should take ADHD medication. He said one simplistic, but still useful, way to decide was to look at guidelines both in the UK and in the US.  NICE guidance published in 2018 and then revised a year later, says that medication should be offered to children who are at least five years old, only if their ADHD symptoms are still causing a persistent significant impairment in at least one domain.

Importantly, after environmental modifications have been implemented and reviewed, it says that every child should get behavioral intervention first, and those who still have significant impairment, should get ADHD medication.

In the US, though, at least according to the American Academy of Pediatrics, the threshold is lower. So there guidance states that for children aged six to 11 years, ADHD medication should be prescribed regardless, along with behavioral treatments. For adolescents the threshold is even lower for ADHD medication because the emphasis is on prescribing ADHD medication. Training and behavioral interventions are encouraged, but not more strongly recommended than that.

He then addressed whether medication is effective in the long term. He said ADHD clearly responds to medication and behavioral treatments in the short term, but evidence for long term effectiveness remains elusive. There were long term outcomes from the MTA study, which found that the intensity of 14 months of treatment for ADHD in childhood (at age 7.0-9.9 years) does not predict functioning six to eight years later. Rather, early ADHD symptom trajectory regardless of treatment type is prognostic.

This finding implies that children with behavioral and sociodemographic advantage, with the best response to any treatment, will have the best long-term prognosis. As a group, however, despite initial symptom improvement during treatment that is largely maintained after treatment, children with combined-type ADHD exhibit significant impairment in adolescence. Therefore innovative treatment approaches targeting specific areas of adolescent impairment are needed.

Finally, Dr Gorman looked at the long-term harms of medication. He said that there were lots of questions about growth, brain development and cardiovascular health  as well as the risk of developing a psychotic disorder or bipolar disorder.

Another long-term study from the MTA compared individuals in their twenties who had consistently taken medication throughout their childhood and adolescence to the group who hardly took medication at all for that decade and more. It found that in the first three years, there was a two centimeter decrement in height in the individuals who had taken medication consistently. More recent data, looking at final height, showed that they didn’t actually catch up as hoped. In fact, they had even more vertical growth suppression totaling about four centimeters. He cautioned that this was actually in a minority of individuals who consistently took medication for over a decade so was only about 7% of the entire sample.

He ended by saying he thought it was very intriguing that despite the common phenomenon of appetite, suppression and weight loss in childhood, as adults, these individuals who had taken medication consistently throughout their childhood and adolescence were actually four and a half kilograms heavier than individuals who had not taken medication during that time.

A patient perspective

Another presentation was given by Kirsty, who was diagnosed with ADHD two years ago when she was 22 years old. She also recently received an autism diagnosis. She spoke about her route to diagnosis.

Kirsty is currently undertaking a Master’s degree on athlete mental health and also plays a lot of sports. She says the structure of sports has been a helpful way for her to manage her ADHD.

It was during the Covid pandemic, when this structure was removed, that she noticed that her ADHD symptoms had gotten worse. It was only when a university friend asked her if she had the condition that she took the questionnaire and sought a formal diagnosis.

She hadn’t considered ADHD before as she had done quite well in school and managed to keep up. But added: “It is mostly obvious to the people that live with me as I lose things and am a bit chaotic, but it’s better now but I’m on medication.”

She said she felt lucky that her process of getting diagnosed was straightforward. Where she is located, she could self refer for an ADHD diagnosis and the wait for the first phone call only took a couple of months. As it was during Covid, she did the questionnaire on the phone with an ADHD nurse. Then following an in-person appointment with a psychiatrist, she tried some medication.

She said it was a big decision to start medication, but her psychiatrist went through the positives and negatives multiple times to help her decide.

She added: “Being on medication has helped me to actually implement other strategies as well. For example, I know if I nap, I can quiet my brain down. There are ups and downs with anything, but I am definitely more level now that I’m on medication.

“The big thing for me was accepting that help is available because I thought I’d done okay with school. But I now have a mentor at university and a housemate who tries to help me remember things as I leave the house.”

Social media and self diagnosis

The final talk was given by Elia Abi-Jaoude, Assistant Professor, and Clinical Investigator in the School of Psychiatry at the University of Toronto. He looked at the role of social media in self diagnosis of ADHD.

He said ADHD was a popular topic on TikTok. Last year, he was involved in a study that looked at the 100 most popular videos on ADHD and evaluated them. These videos had combined views of over 280 million and just over half were classified as misleading or inaccurate. The ADHD hashtag at the time had over 4.3 billion views. A year later, this was over 10 billion. Now it is well over 20 billion views.

He added that in many cases, this popularity will have positive effects and might help someone who was struggling with certain things to reach a diagnosis that was not previously recognised. However, he also added that it has made a lot of people start interpreting their experiences in in clinical terms, and maybe having labels that might not be the most helpful for them.

In addition, viewers of these videos could get targeted adverts, including for private online clinics that can diagnose ADHD for a fee. They could also get targeted adverts for medications.

Professor Abi-Jaoude said if someone is struggling to understand some of their experiences and why they are struggling, it is very easy to start to consider different labels and see if that explains the experiences.

He added that we live in a world where we are constantly bombarded with all sorts of stimulation and gadgets that are highly distracting in anything that we are trying to do.

There is also overwhelming evidence about how these gadgets  impact our sleep in a negative way and our ability to focus and pay attention. We also might be experiencing a lot of stress due to the increased expectations on society today compared to even 20 years ago.

He added: “So, we’re constantly struggling and feeling inadequate and we might start wondering whether there’s a clinical reason that can explain this. Could this be ADHD? Then we’re bombarded by marketing, whether it’s from the pharmaceutical industry or others.

“A diagnosis can be a very useful thing, but a pitfall is taking on an illness identity that means we might miss out on opportunities to address other issues that could be contributing. We also end up flooding our public health system, or even the private one, which can make it more difficult to provide care for all the people.”

The webinar can be accessed here.

Alison Bloomer

Alison Bloomer is Editor of Learning Disability Today. She has over 25 years of experience writing for medical journals and trade publications. Subjects include healthcare, pharmaceuticals, disability, insurance, stock market and emerging technologies. She is also a mother to a gorgeous 13-year-old boy who has a learning disability.

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