ADHD seems to be in the news everywhere, but is this due to a rise in cases or to changing awareness and diagnosis? Pulling together the evidence for a presentation to Europe's main clinical neuroscience conference, Professor Anita Thapar will say "The rise in cases of ADHD across Europe appears mainly due to a change in awareness and diagnosis. Indeed, there is growing evidence that ADHD is still under-diagnosed in some countries".
Professor Thapar (of Cardiff University) chaired the NHS England ADHD taskforce and co-chaired the Welsh Government Neurodivergence Ministerial Advisory Group. She will be the main speaker/facilitator at a session at the 39th ECNP congress, discussing why referrals and treatment for ADHD are increasing across the UK and Europe, despite evidence that underlying population prevalence has not risen. The discussion will focus mainly on UK data and evidence, while drawing on findings relevant to other European countries.
Professor Thapar continued, "My overview of the ADHD situation brings together several recent strands of evidence. Yes, ADHD diagnoses have risen across Europe, but this seems to be due to changes in diagnostic criteria, improved awareness and research evidence on ADHD and its risks, rather than to an epidemic of ADHD. It is now being recognised, whereas in the past it wasn't. You sometimes see this with medical conditions, for example conditions like high lipid levels and hypertension and their risks were not widely recognised in the 1960s. The same for ADHD."
Evidence cited will confirm that the diagnosed prevalence (the total number of clinically diagnosed cases) of ADHD has increased significantly in the last few years. In some countries, recognised ADHD rates now match the population rate, in others (e.g. UK) it is well below the population rate (the expected rate of ADHD diagnosis in the population). The population rate of ADHD is approximately 5–7% of children and 2–3% of adults across Europe. In addition, the number of people receiving medication has significantly increased. A recent publication reported increased ADHD medication use in Belgium, Germany, the Netherlands, Spain and the UK between 2010 and 2023. In the UK, prevalence of medication use rose more than threefold in this period, from 0.12% to 0.39%, while adult use increased particularly sharply among women.
Professor Thapar said "We believe that there are several possible reasons for the rise in diagnoses including improved public and professional awareness and recognition. Although some raise concerns about potential misdiagnosis, research evidence here is limited. The way that ADHD has been defined has changed over time, which means the threshold for treatment has also moved. That has also happened for other conditions ( for example the thresholds for treating high blood pressure and high lipid levels have also changed). There is now greater awareness that ADHD can affect adults, and there is much stronger evidence of the condition developing in women and girls – something which was neglected in the past. Also, there is evidence now that treatment can reduce known risks of ADHD such as premature mortality or suicide.
We also need to consider that "having" ADHD isn't a simple yes or no. As in conditions such as high blood pressure, or high cholesterol, the degree of the condition can vary along a spectrum and the point where doctors intervene (i.e. a diagnostic threshold is reached and treatment indicated) can change over time in line with research evidence. Guidelines typically suggest starting with non-pharmacological support and then ADHD medication if these other strategies are insufficient. Interestingly, the rate at which ADHD is seen in clinics is lower than the true rate of ADHD in the population, suggesting ADHD is actually under-recognised and under treated in the UK.
This reflects the fact that population ADHD prevalence estimates are broadly consistent across European countries, but the number of people formally recognised or treated within health systems varies considerably depending on service provision, access to assessment and clinical practice".
The ADHD session in Munich will be an open discussion on what is driving the increase in referrals, and how healthcare systems can respond to rising demand while ensuring that people who may have ADHD receive appropriate assessment and support.
Commenting, Prof. Barbara Franke (Radboud University, Nijmegen, The Netherlands) said:
"For years, ADHD researchers have done their best to raise the awareness that ADHD is underdiagnosed in females and adults in general. Over the last years, this knowledge finally takes hold in the population, but with such speed that it feels like an epidemic. Despite the relatively high prevalence and the burden associated with it, however, funding for research into ADHD – from its aetiology to its treatment – is surprisingly hard to find, and ADHD unfortunately still remains one of the most under-researched conditions in medicine. I sincerely hope that we can change that, too.'
This is an independent comment; Prof. Franke was not involved in this research.
The introductory discussion will focus mainly on UK data and evidence, while drawing on findings relevant to other European countries. This is a discussion group for all participants.
