How many of us will eventually be diagnosed?

The number of people taking ADHD medication is at record highs, and the NHS is feeling the strain as it tries to diagnose and treat the disorder.

The number of people taking ADHD drugs in England has almost tripled since 2015, and BBC research It is recommended that it take eight years to assess all adults on the waiting list.

Last year ADHD was the second most viewed condition on the NHS website. Concerns about this growing demand have prompted the UK's National Health Service (NHS) to Establish working group.

So what exactly happens and where does it end? Is ADHD (Attention Deficit Hyperactivity Disorder) becoming more common? Are we just getting to know it better? Or is it overdiagnosed?

As it turns out, it's not just you and me who are surprised, but the experts too.

“No one expected such a huge increase in demand over the past 15 years, and particularly over the past three years,” said Dr. Ulrich Müller-Sedgwick, ADHD champion at the Royal College of Psychiatrists, who has run an adult ADHD clinic since 2007. At the time, he said, there were only a few clinics.

ADHD is a fairly new condition – it's only been 16 years since the National Institute for Health and Care Excellence (NICE) officially recognized ADHD in adults. When considering whether the increase will continue, Dr. Mueller-Sedgwick believes two different concepts need to be considered: prevalence and incidence.

Prevalence refers to the percentage of people with ADHD – Dr Müller-Sedgwick predicts that the proportion of UK adults with ADHD will stabilize at 3 to 4 per cent.

Incidence refers to the number of new cases—the number of people diagnosed. That's where we're seeing growth. “What changes is the number of patients we are diagnosing. It's almost like the more we diagnose, the more the word spreads,” he explained.

Professor Emily Simonoff agrees. She is a child and adolescent psychiatrist at the King's Maudsley Child and Adolescent Partnership. She believes around 5 to 7 per cent of children in the UK have ADHD, and said: “It's very similar around the world, it's been consistent and it's not really rising.”

Professor Simonov agreed there had been a “dramatic increase” in the number of people coming forward for assessment since the pandemic, but said this followed years of “chronic under-recognition”.

She points to statistics on ADHD medications. She estimates that around 3% to 4% of children in the UK need ADHD medication, but in reality, only 1% to 2% actually use it. She believes this shows we are still underestimating the scale of the problem.

Professor Simonov explained: “I think this is an important starting point when we say 'Oh my gosh, why are we seeing so many kids now – are we over-identifying ADHD?'” In the UK, for many years we have had ADHD is underdiagnosed or underrecognized. “

In other words, we can expect more people to be diagnosed with ADHD now because services are catching up.

Thea Stein is chief executive of health think tank the Nuffield Trust. She has her own way of describing the recent increase in demand: a “hump.” “The desire to diagnose or be diagnosed increases because of knowledge and visibility – (it’s that) simple,” she said.

Stein said the most urgent task is to get through this and assess the massive backlog of people on ADHD waiting lists. Then, in the long term, she thinks society will be better off detecting ADHD in children more quickly. She hopes it means they get better support from an early age and takes some of the pressure off adult services.

“I'm very optimistic that our society will get through this and move to a better place. What I'm not optimistic about is that this is just a quick fix,” she said.

ADHD may be a new concept, but people's difficulty concentrating is an old problem.

In 1798, the Scottish physician Sir Alexander Crichton described a “disease of inattention” accompanied by “an unnatural degree of uneasiness of mind.”

“When people are affected by this… they say they're restless,” he explained.

ADHD isn't just a matter of inattention or hyperactivity, though. People with this disorder may have difficulty controlling their emotions and impulses. It's been linked to substance abuse and financial hardship, as well as higher crime rates and even car crashes.

All the experts I spoke with firmly agreed on this: It's far better for people with ADHD to diagnose and treat it as early as possible.

Dr Mueller-Sedgwick said there was a “risk of very bad outcomes”. But when he describes how diagnosis and treatment can change lives, his eyes light up.

He said: “I've seen a lot of patients get better and go back to work or education. I've seen parents who were going through family court proceedings become better parents.

“That's why we work in this area, it's a very rewarding part of the mental health field.”

Currently, ADHD treatment mainly revolves around medication and therapy, but there are other options.

A patch that children with ADHD wear on their foreheads while sleeping – connected to a device that sends stimulation pulses to the brain – is being sold in the United States. It is not regulated in the UK, but academics in the UK and US are conducting clinical trials to study it.

Professor Katya Rubia is a professor of cognitive neuroscience at King's College London and, as she puts it, “My work over the past 30 years or so has been basically imaging ADHD and understanding what's different in the brain[of people with ADHD].”

She explained that certain parts of the ADHD brain, including the frontal lobes, are slightly smaller and less active. Professor Rubia is trying to activate these areas of the brain and is conducting a study on the trigeminal nerve – which goes directly into the brainstem and can increase activity in the frontal lobes.

“It's all very new,” she said. “If we find an effect, we'll have a new treatment.” While this has yet to be proven, she added: “If all goes well, it could be on the market within two years.” “

So hopefully, in the near future, there will be more ways to treat ADHD that don’t require medication. But in the meantime, the challenge is how to get through the “peak” of waiting assessments – it is believed that the increase in diagnoses should decrease over time.

See the BBC Actionline for support with ADHD issues

Read NHS advice on ADHD

Above: Getty Images

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