Sharp rise in ADHD diagnoses – as waiting lists grow longer

New research has found that far more people are now diagnosed with ADHD than 20 years ago, with the highest absolute increase seen in children

18th July 2023 about a 4 minute read
“Whilst ADHD is most likely to be diagnosed in childhood, an increasing number of people are diagnosed for the first time in adulthood. We do not know exactly why this is happening, but it may be that ADHD has become better recognised and diagnosed." Dr Doug McKechnie, clinical research fellow, UCL Institute of Epidemiology and Health Care

The number of people diagnosed with attention-deficit hyperactivity disorder (ADHD) has increased sharply in 18 years, a study has found.

Researchers from University College London (UCL) analysed data from seven million people of all ages between 2000 and 2018. Of these, 35,877 had an ADHD diagnosis and 18,518 had received prescriptions for ADHD medication from their GP. In the 18-year period, there was a 20-fold increase in ADHD diagnoses and a nearly 50-fold increase in ADHD prescriptions in men between the ages of 18-29 (from 0.01 per cent to 0.56 per cent).

ADHD was more commonly diagnosed in children than adults, the researchers found, and in boys and men rather than girls and women. By 2018, there were 255 ADHD diagnoses per 10,000 among boys, and 67.7 per 10,000 among girls. In adults, there were 74.3 diagnoses per 10, 000 in men and 20 per 10, 000 in women.

In absolute terms, the highest increase was seen in children. Among boys aged 10-16, there was a 2.1% rise in the number of ADHD diagnoses and a 1.8% rise in the number of ADHD prescriptions between 2000 and 2018.

The study’s lead author, Dr Doug McKechnie, of the UCL Institute of Epidemiology and Health Care, said: “ADHD diagnoses and prescriptions for ADHD medication by a GP have become more common over time.

“Whilst ADHD is most likely to be diagnosed in childhood, an increasing number of people are diagnosed for the first time in adulthood. We do not know exactly why this is happening, but it may be that ADHD has become better recognised and diagnosed.

“Over the last few years, there have been many reports of long waiting lists for ADHD assessments on the NHS, especially in adults. It’s likely that more and more people will be diagnosed with, and treated for, ADHD, so specialist services need to be made available to handle this.

“Many people are accessing private care for ADHD. This may create healthcare inequalities given that ADHD is more common in deprived areas. People living in deprived areas may not be able to afford private healthcare, and may suffer with undiagnosed and untreated symptoms of ADHD for longer.”

An average waiting time of 16 months for treatment

Separate research carried out by House magazine shows that children with suspected ADHD and autism are waiting up to seven years for treatment on the NHS. The average waiting time, the research found, was 16 months. This is three times longer than the average wait for all child and adolescent mental health services (Camhs).

Half of all trusts responding to a freedom of information request had an average wait of at least a year, and at one-sixth of trusts it was more than two years. The NICE guidance for autism and mental health services states that no one should wait longer than 13 weeks between being referred and first being seen.

There was a lot of variation in waiting times. In Belfast, children with suspected ADHD are waiting an average of five years for an initial appointment, and the longest wait for neurodevelopmental treatment was seven years. In Oxford, the longest wait was five years and 14 weeks, while in Coventry and Warwickshire, which had the worst record in England, there was an average wait of 142 weeks for all neuro first appointments.

A spokesperson for the Oxford health trust said: “The number and complexity of referrals to our services have increased significantly and our funding has not increased.”

Henry Shelford, the CEO and co-founder of ADHD UK, said people with ADHD were at greater risk of taking their own lives, adding: “Yet we are hearing again and again that unless a child is at serious risk of harm they are not a priority, they are pushed to the back of a very long queue,” he said. “It is inhumane to make children wait until they are suicidal before helping them.”


FCC Insight

The increase in the number of people receiving a diagnosis of ADHD since 2000 has been so dramatic that it’s not surprising that there are long waiting lists for both diagnosis and treatment. While there is a clear need for greater resourcing for neurodevelopmental disorders, we also need to look at whether increased diagnosis represents an increase in numbers of people who have ADHD, a greater willingness of health professionals to diagnose it or simply a wider public awareness of the condition.