German study first to show direct medical costs of ADHD and its comorbid conditions across the lifespan

Having ADHD is expensive. A study of German insurance data has shown that the medical costs of a person with ADHD are 1500 euro higher per year, compared to a person without ADHD. But that’s not all; individuals with ADHD are far more likely to suffer from additional conditions such as mood and anxiety problems, substance abuse or obesity. Treatment of these conditions can cost up to an additional 2800 euro per year. As ADHD – especially in adults – is still poorly recognised and diagnosed, these numbers may not reflect the complete picture of ADHD medical costs. Improving diagnosis and adult mental healthcare may prevent mental health problems later in life and actually reduce costs, argue Berit Libutzki and her co-authors.

ADHD (Attention Deficit / Hyperactivity Disorder) is a developmental condition. Symptoms arise before the age of 12 and are characterised by age-inappropriate and impairing behaviour in terms of problems with attention, impulsivity and hyperactivity. World-wide prevalence of children with ADHD is estimated around 5%, while in adults this is around 2.5%. This means that in about half of the children problems do not subside with age. For these people, ADHD is a lifelong condition that often impairs health, career and social life.

To estimate the economical costs of ADHD, Berit Libutzki and her colleagues from HGC Healthcare Consultants GmbH analysed the (anonymised) health insurance data of almost four million Germans. They compared the medical costs of people with an ADHD diagnosis to those of a well-matched group without ADHD.

medical costs per person_figure

The results showed that the medical costs of a person with ADHD are on average 1508 euro higher than those of a person without ADHD. These costs are mainly due to treatments in hospitals and by psychiatrists. ADHD medication itself (such as Methylphenidate) are in third place, contributing to only 11% of the additional costs. Other interesting findings from the study are that medical costs are a bit higher in women compared to men, and that costs are much higher in individuals over 30 years old compared to younger age groups. After the age of 18, the costs of for example ADHD medication drop, while psychiatrist costs and costs for other (non-ADHD) medications increase notably. Also sick payment is high in adult ADHD patients, leading to a significant increase in costs. One of the explanations for these cost increases could be a gap in care after leaving the regular care of a paediatrician at age 18, and the development of disorders that arise in addition to ADHD.

medical costs increase_figure

ADHD plus additional (mental) health problems

It has been shown before that having ADHD puts you at a much higher risk of developing additional (comorbid) disorders. Mood disorders – such as depression – and anxiety are most frequent; in the German data two-thirds of ADHD individuals over 30 had such an additional diagnosis (compared to only a fifth of adults without ADHD). Substance abuse and obesity are more common in people with ADHD as well. These comorbidities should not be underestimated as they add strongly to the burden of disease. The study shows that substance abuse and morbid obesity are even the most costly, especially in adulthood. In total, the surplus costs associated with these conditions are 1420-2715 euro higher for ADHD individuals, compared to individuals who suffer from mood or anxiety disorder, substance abuse, or obesity alone.

comorbid disorders_figure

Scientists think that certain genetic factors that play a role in ADHD also make a person more vulnerable for these comorbid health conditions. Libutzki and her team are part of the European research consortium Comorbid Conditions of ADHD (CoCA) that investigates the shared biological mechanisms of ADHD and these additional disorders. “Through this research we hope to find leads to prevent these disorders from developing, and improve mental health care.”, says the leader of the CoCA consortium Prof. Dr. Andreas Reif of the University Hospital Frankfurt.

“It is intriguing to speculate that these comorbidities, which were shown to be the important cost drivers in adulthood, could be prevented if mental healthcare were provided more constantly over the lifespan” write the authors. “The prevention of the development of comorbidities with age should be the focus of mental health care. Early treatment starting in childhood and continued treatment of adolescents into adulthood seem therefore advisable.”

Improving diagnosis and adult mental health care

There is one caveat in the study by Libutzki, that is also acknowledged by the authors: many people, especially adults, are not diagnosed with ADHD, even though they experience the symptoms. “Our knowledge gap is especially large in adulthood”, says Dr. Catharina Hartman from the University Medical Centre Groningen, The Netherlands. “The prevalence of adult ADHD in the health insurance data was very low (0.2 %). Given that the population prevalence for adult ADHD is 2,5 %, this indicates that many adults with ADHD are currently not diagnosed or treated. They may nonetheless make high direct costs since their ADHD may not be recognised, or they make indirect costs through unemployment or criminality.” This would indicate that the costs reported by the study are underestimated. On the other hand, adults often find out about their ADHD only after consulting a psychiatrist for other mental health problems. This would indicate that estimated costs and prevalence of comorbid disorders with ADHD in adulthood are overestimated, compared to when you were to include also all undiagnosed people with ADHD, and diagnosed persons who do not make costs (i.e. milder cases of ADHD).

The study thus provides a partial view on the costs of ADHD during the lifespan. That said, it is among the first to show in detail the lifespan medical costs of ADHD and comorbid disorders in Germany. These findings are likely to be representative of other western-European countries. Policy makers in these countries are strongly advised to investigate ways to improve the transition from child to adult mental healthcare and increase awareness about adult ADHD. This will not only improve the quality of life of many adults but may also save money.

Further reading

Libutzki, Ludwig, May, Jacobsen, Reif and Hartman (2019). Direct medical costs of ADHD and its comorbid conditions on basis of claims data analysis.  European Psychiatry, 58: 38-44. https://www.europsy-journal.com/article/S0924-9338(19)30019-7/abstract

The findings from this study are also summarised in an infographic: https://my.visme.co/projects/1jok0qg8-medical-costs-adhd

Mini-documentary: “Shine a light – understanding ADHD”

On the last day of the international ADHD Awareness Month, we are releasing a mini-documentary about ADHD. The hope is that this video will help young people and adults diagnosed with ADHD, or who suspect they have ADHD, as well as their family and friends, to understand the condition better.

“I feel like a universe, stuffed within a shoebox” – this is how Bryn Travers describes what it’s like to have Attention Deficit / Hyperactivity Disorder (ADHD). In this short film we have asked people with ADHD and their relatives about living with ADHD: what are the challenges and what are the things they like about ADHD? We have also asked clinicians and researchers working with ADHD to explain more about the origins of the disorder, what they have learnt from their experience working with patients, but also what are the main questions that research is trying to answer about ADHD.

Many children, adolescents and adults suffer from ADHD. ADHD is a complex disorder that affects people differently. Generally people experience problems in daily life, especially with respect to controlling attention, impulses and emotions. At the same time, people with ADHD enjoy their creativity and positive energy. Medication is effective for many people with ADHD, but not for all. That is why many people are interested in other types of (additional) treatment, such as meditation or diets. These types of treatment should therefore be better investigated. Knowing more about ADHD and spreading awareness will help people to understand what causes their behaviour. This will reduce stigma and (self)blame.

The video features four of the most well-known researchers in the field of ADHD: dr. Eric Taylor is emeritus professor of Child and Adolescent Psychiatry at King’s College London, dr. Philip Asherson is professor of Molecular Psychiatry at King’s College London, dr. Barbara Franke is professor of Molecular Psychiatry at Radboud university medical center Nijmegen (The Netherlands), and dr. Corina Greven is psychologist and behavioural geneticist at Radboud university medical center Nijmegen. Next to these scientists and psychiatrists, we see three people with ADHD (Bryn Travers, Evie Travers and Aziz), Andrea Bilbow, president of patient organisation ‘ADHD Europe’ and mother of two children with ADHD, and dr. Kai Syng Tan, researcher and artist at King’s College London, who also has an ADHD diagnosis.

This film was created through the MiND research consortium, in collaboration with the consortia Aggressotype, CoCA and Eat2beNICE. These consortia are all funded by the European Commission through the FP-7 and horizon2020 programs. Young researchers dr. Nicoletta Adamo and Laura Ghirardi are the brains behind this film, with the help of the MiND training program and 4QuarterFilms.

Do you want to help us spreading awareness about ADHD? Then share this video with everyone you know! The video also contains subtitles in English, Dutch, German, Spanish, Italian, Swedish and Hungarian (and more languages may follow).

You can watch the video here:

It’s ADHD awareness month!

ADHDAwarenessMonth_Color_Large-5a76306eae9ab80036d0171c

October is the international ADHD awareness month. This initiative of the European ADHD patient organisations aims to raise awareness about ADHD, and funding for more research to understand ADHD. Throughout Europe many events will be organised this month to inform people about ADHD. Because although most people have heard about ADHD, there are still a lot of misconceptions and misunderstandings of what ADHD really is.

This year’s theme of the ADHD awareness month is ADHD and employment. As ADHD is increasingly being recognised as persisting into adulthood, ADHD on the work floor is something to take into account as well. The bad news is that unemployment rates are higher for people with ADHD [1] as well as the number of absence days and turnover rates [2]. But the good news is that ADHD is often associated with entrepreneurship. For instance, a large registry-based study showed that a high number of hyperactive symptoms is related to a high chance of being self-employed [3].

According to Andrea Bilbow, president of the European organisation ADHD Europe, “it should be more widely known that people with ADHD have great skills to offer to employers. It is important for employers to understand that ADHD is a disability, and that people with ADHD can be a great asset if you find their strengths. Employers should be aware that if you help employees with ADHD to scaffold the things they’re less good at, then they can excel at the things they are good at. For instance, in general people with ADHD are very good in IT, in problem solving, and in fixing things. They are often less good at paper work and processing a lot of information. So one piece of advice is to not overload them with too many instructions. Instead, if you give them one task at a time and they will do task incredibly well.” So are you an ADHD-friendly employer? We previously posted a blog on this.

The ADHD researchers that are affiliated with the MiND the gap-blog are also contributing to ADHD awareness month. We will be posting several blogs this month about our ongoing studies and recent publications on ADHD and comorbid disorders (i.e. from the CoCA project). Furthermore, at several European sites researchers are organising events to raise awareness about ADHD. In Nijmegen, The Netherlands, for instance you can come to the university’s open day on October 6 and draw your own superhero with ADHD (you can even win a prize!). Also check out the website of the ADHD patient organisation in your country or city to find out more about what’s happening.

Last, but definitely not least, we will soon be releasing a short documentary about ADHD that was created through the MiND-project, in collaboration with the other EU-funded projects and research consotira (Aggressotype, CoCA and Eat2BeNICE, IMpACT). So keep following this blog for updates, and spread the word about ADHD awareness!

For more information about ADHD awareness month, visit the website of ADHD Europe: https://www.adhdeurope.eu/

 

Jeanette Mostert is dissemination manager for the projects CoCA and New Brain Nutrition (Eat2BeNice).

 Further reading

[1] Kuriyan, A.B., Pelham, W.E., Molina, B.S.G. et al. (2013) Young Adult Educational and Vocational Outcomes of Children Diagnosed with ADHD. J Abnorm Child Psychol, 41: 27-41. https://doi.org/10.1007/s10802-012-9658-z

[2] Kleinman, N.L., Durkin, M., Melkonian, A., Markosyan, K. (2009) Incremental Employee Health Benefit Costs, Absence Days, and Turnover Among Employees With ADHD and Among Employees With Children With ADHD. Journal of Occupational and Environmental Medicine, 51: 1247-1255 doi: 10.1097/JOM.0b013e3181bca68c

[3] Verheul, I., Rietdijk, W., Block, J. et al. (2016) The association between attention-deficit/hyperactivity (ADHD) symptoms and self-employment. Eur J Epidemiol, 31: 793. https://doi.org/10.1007/s10654-016-0159-1

Exciting findings on ADHD comorbidities shared on 3rd meeting of CoCA researchers in Dublin

A few weeks ago, researches from all over Europe (and some even from the USA) gathered in Dublin to discuss the progress of the CoCA project. This project, investigating the prevalence and causal factors of ADHD comorbidities, is now almost half way. Time for an update on what’s happening. 

CoCA Dublin
All attendees of CoCA’s 3rd general assembly meeting in Dublin

ADHD is a risk factor for developing other (psychiatric) disorders

One of CoCA’s aims is to estimate the prevalence of comorbid disorders that occur together with ADHD. By using very large data registries from Norway, Sweden, Denmark and Estonia we can estimate the risk of developing a psychiatric comorbidity when a person has ADHD. For instance, last month a paper was published based on data from Norway, stating that the prevalence of anxiety, depression, bipolar and personality disorders, schizophrenia and substance use disorders is 4 to 9 times higher in adults with ADHD compared to adults without ADHD [1]. Interesting differences between men and women were also observed in this study. Such that depression is much more prevalent in women with ADHD, compared to women without, while in men substance use disorders are more common together with ADHD.

ADHD does not only co-occur with other psychiatric disorders, but also with obesity. Earlier last year, we published a study based on the Swedish national registry, where it was observed that ADHD and being overweight or having obesity share familial risk factors [2]. In other words, when you have a sibling who is overweight or has obesity, you are more likely to have ADHD compared to similar people who do not have overweight siblings.

The data from these registries can not only be used to estimate prevalence, but also to predict the risk someone has to develop other disorders. Our partners in the USA are using advanced machine learning tools to predict within the ADHD population who will develop comorbid disorders. Using the Swedish registry data they have found that having an ADHD diagnosis combined with a high number of injuries before the age of 12 predicts a comorbid substance use disorder at a later age. High risk taking behavior could mediate this association, and may therefore be a trait to investigate further and monitor in young people with ADHD. These data are now being further investigated and have not yet been published.

Publications on other registries and data will come out soon, so keep your eye on this blog for more information on the co-occurrence of (psychiatric) disorders in persons with ADHD.

ADHD and (psychiatric) comorbidities share genetic variants

When you know that ADHD often co-occurs with other disorders, the next question is to understand how and why. Our geneticists are trying to map the genetic overlap between the different disorders and identify shared genetic risks. Much of the work is still ongoing, but you can expect some exciting findings to be published very soon. What I can already share is the recent publication on how polygenic risk scores of ADHD overlap with other disorders and traits [3]. Polygenic risk scores (PRS) were calculated based on 12 genetic loci that are associated with ADHD based on earlier studies. In other words, the more risk variants you have on these loci, the higher your risk is for ADHD. Using the UK Biobank data, the researchers found that ADHD PRS were associated with higher body mass index, neuroticism, anxiety, depression, alcohol and nicotine use, risk taking and lower general cognitive ability (verbal-numerical reasoning). This suggests that the genes that contribute to ADHD are also involved in other traits and disorders that are often observed in people with ADHD. More knowledge on these genetic factors is expected from the studies that are now being conducted.

Searching for new treatment possibilities for ADHD and comorbid disorders

At the moment, there are no good treatments for obesity and substance use disorders, and there is little progress in the development of medication for ADHD in combination with depression. Within the CoCA project we are therefore investigating new treatment possibilities. In Frankfurt, Barcelona and London the first people with ADHD have received bright light therapy and physical exercise training to reduce symptoms of depression (the PROUD study). In Nijmegen this study will soon start as well. Meanwhile in Rostock (Germany), the circadian rhythm of participants with ADHD and other disorders is being measured. And in Frankfurt researchers are investigating the effects of dopamine agonists and antagonists on the reward system in the brain.

CoCA researchers in Norway have been searching the literature for new druggable targets for ADHD and comorbid disorders. A publication on many promising druggable genes can be expected soon. The first group of targets will be tested in an animal models.

Collaborations with patient organisations

Two representatives of ADHD patient organisations also joined our meeting: Andrea Bilbow from ADHD Europe, who is a partner in the CoCA project, and Ken Kilbride from ADHD Ireland. It was good to have these experts with us, and discuss with them how we can best translate our research findings to the people who should benefit from these findings. In Ireland for instance, there is very little knowledge about adult ADHD amongst health care professionals. It is therefore essential that our knowledge is also transferred to them, so that they can provide better care.

With the help of Andrea and Ken, we came up with a lot of new ideas for ADHD Awareness Month. During the entire month of October we aim to generate more awareness about. We will specifically target schools, such as universities and German Berufschule to inform both pupils and teachers about how to recognise ADHD and comorbidities, in adolescence and adulthood.

What’s next?

With the project being almost half way, we feel that we’re progressing very well (and our external advisor Jim Swanson – who attend the meeting as well – agrees!). In the coming year, we expect many exciting publications to appear and we will organise several symposia on international scientific conferences to share with you what we’ve found. By collaborating with patient organisations across Europe we will also share our knowledge with patients, family members, health care professionals and teachers. You can follow all of our progress on this blog!

This blog was written by Jeanette Mostert. Jeanette is dissemination manager of the CoCA project.

Further reading

1: Solberg, Halmøy, Engeland, Igland, HAavik & Kungsøyr (2018) Gender differences in psychiatric comorbidity: a population‐based study of 40 000 adults with attention deficit hyperactivity disorder. Acat Psychiatria Scandinavia, 137 (3): 176 – 186. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5838558/

2: Chen, Kuja-Halkola, Sjölander, Serlachius, Cortese, Farone, Almgvist & Larsson (2017) Shared familial risk factors between attention-deficit/hyperactivity disorder and overweight/obesity – a population-based familial coaggregation study in Sweden. Journal of child psychology and psychiatry, 58 (6): 711-718. https://www.ncbi.nlm.nih.gov/pubmed/28121008

3: Du Rietz, Coleman, Glanville, Wan Choi, O’Reilly & Kuntsi (2018) Association of Polygenic Risk for AttentionDeficit/Hyperactivity Disorder With Co-occurring Traits and Disorders. Biological Psychiary CNNI, in press. https://www.sciencedirect.com/science/article/pii/S2451902217302318?via%3Dihub

 

 

The up-goer five of ADHD

Launch of the Saturn V space shuttle (Wikimedia commons / by NASA)

Can you explain your research using only the thousand most common words in the English language? This challenge has been going around since Randall Munroe (famous for the xkcd comics) published a comic in which he explains how the Saturn V space shuttle works using only sketches and the thousand most common words. Hence the name up-goer five, as both the words shuttle and rocket are not in that list. The fun thing about this challenge is that it makes you think about what your research is really about, and formulate this using normal, everyday language.

As dissemination manager of CoCA (i.e. the person who tells other people what we find in our studies), I took it upon me to describe the CoCA project using only these thousand most common words. Luckily, someone was kind enough to create an online tool that tells you when you’re using a word that’s not in the list (so now I know that project and research are not allowed, but studies is. Yay!).

Now before I show to you the result of my effort, let me first write a disclaimer. One of the nice things about the richness of language is that you can use it for nuances. And nuance is something that scientists love. By specifically choosing your words, you can make clear what you mean exactly. Jargon helps us even more in this, because everyone else who knows this jargon knows exactly what you mean. Anyway, the disclaimer here is that if you use only the most common thousand words, you lose nuance. So  I know that ‘a person who cannot sit still and pay attention’ is a very poor description of a person with ADHD. But I challenge you to do better!

So here it goes, the CoCA project described in common English:

We study why people who can’t sit still and pay attention also often feel sad, or eat too much, or use too much of things that are not good for them and can’t stop with it. They have these problems more often than people who are better at sitting still and paying attention, and the problems get worse when they become older. We think that this is because their brain works a bit different. We try to help them by making them jump and run every day, and by giving them more light. And we give them a phone to show them what they should do, and how good they are doing each day. The jumping and running and more light each day should make them more happy. We also look in their brains for things that cause both not sitting still and eating too much, or not paying attention and feeling sad. When we understand better how these things in our brains can cause these problems, we can help the people who have these problems to get better.

What do you think? Does this help you to understand what the project is about? Or does it remain very vague (what problems? Which things in brains?).

I’m very curious to see if other CoCA researchers can do a better job at this. Or maybe they can describe their parts in the project using this online tool. And researchers from the other projects, Aggressotype, MiND, can use the tool to describe their projects. Challenge accepted?

Try it out yourself: http://splasho.com/upgoer5/ (or use the Norwegian or Spanish version!)

And in case you are now very curious about what the CoCA project is really about, you can read more about it here.

This post was written by Jeanette Mostert. Jeanette is dissemination manager of the CoCA project.

How bright light and physical exercise might help ADHD patients

Attention deficit hyperactivity disorder (ADHD) is a mental health condition that rarely occurs alone. More than 80 percent of adult ADHD patients suffer from a comorbid disorder, meaning there is at least one additional disease co-occuring with the primary disease.

In the case of ADHD, two common comorbid conditions are obesity and major depressive disorder. Therefore, the risk for comorbid obesity and major depressive disorder is increased in adolescents and adults with ADHD. Moreover, a disturbed circadian rhythm and altered sleep are key features of ADHD.

Bright light therapy, a so-called chronobiological modification, improves the day-night (circadian) rhythm and is an established therapy for major depression in adolescents and adults. Exercise prevents and reduces obesity in adolescents and adults along with improving depressive symptoms.

While these non-pharmacologic treatments are known to modulate dopaminergic transmission (DA) and circadian rhythm (CIRCA), two key mechanisms regulating mental wellbeing, no study has assessed their effect on ADHD and its comorbidities in an experimental setting yet. PROUD is therefore the first large scale, multicentre study to systematically evaluate the role of DA and CIRCA and scrutinize their potential relevance for developing disease biomarkers and thus obtaining measurable indicators for predicting and treating these ADHD comorbidities.

“The idea here is to employ non-pharmacological methods to improve patients’ lives. There is a well-established drug treatment for ADHD with stimulants – methylphenidate being the most famous one. However, that is only one step and we want to make use of the knowledge that sports on the one hand and bright light therapy on the other hand showed promising initial data to improve patients’ lives with ADHD”, says CoCA project coordinator Andreas Reif, Chair of the Department of Psychiatry, Psychosomatic Medicine and Psychotherapy at the University Hospital Frankfurt in Germany.

“So we put that into a clinical study where we compared treatment as usual with add-on sports therapy or add-on bright light therapy. Over this ten-week trial, we will see whether this affects not only ADHD symptoms but overall health symptoms like depressive symptoms or weight.” 

Need a watchdog or motivator? There’s an app for that

Just how do you motivate obese patients to exercise regularly? “It’s very hard to get up and do sports on a daily basis”, says Reif. “We thought about how we can empower our patients to adhere to the study protocol. In order to do that, we have developed a mobile health application, the mHealth App.”

The mHealth App was specifically developed for the PROUD Study with the aim of keeping the patients motivated. “We achieve this by showing them videos of exercise, sending reminders as well as a daily feedback and summary on their achievements”, trial coordinator Jutta Mayer explains.

The study has started with its first participants at the University Hospital of Frankfurt in late March 2017. The CoCA team expects first results and insights by the end of 2017.

This post was written by Thomas Wagner-Nagy (concentris research management GmbH) and has also been submitted as a press-release to announce the start of the PROUD trial.

Our ADHD researchers in the media – Explaining the biology and treatment of ADHD

A short while ago, three of our professors were in the media, featuring an article and a TV-documentary about ADHD. Professor Andreas Reif wrote an elegant piece for the Frankfurter Algemeine – a German national newspaper – explaining the biology of ADHD and the need for treatment [see also this recent post on Andreas Reif’s recent appearances in German Media]. Around the same time, professors Barbara Franke and Phillip Asherson appeared in a documentary in which Britisch comedian Rory Bremner went on a personal mission to discover the science of ADHD. As not everyone can read German, and the BBC show is unfortunately only viewable inside the UK, I’ll tell you about the highlights of both pieces.

Fidgety Philip

Do you know the stories by Heinrich Hoffman (1845)? The psychiatrist who wrote a children’s book about naughty children. One of the stories is about Fidgety Philip – or Zappelphilip in German – a boy who can’t sit still and as a result pulls down the tablecloth including everything that’s on top of it, smashing all the table’s contents on the floor. Both Andreas Reif and Rory Bremner mention Fidgety Philip, as the characteristics of this boy resemble several symptoms of ADHD: fidgetiness, restlessness and impulsivity. This example illustrates that ADHD is not a new or modern day phenomenon.

Busy brains

Interestingly, it’s not just the behaviour of people with ADHD that is restless. As Rory Bremner describes it “the music in my brain is [..] pounding and rapid and switching”. This ‘busy brain’ is often described by people with ADHD. And this makes it logical to expect that you should be able to see this with an MRI-scanner – a machine that allows researchers to measure brain activity. Unfortunately, reality is not so simple. Despite a lot of research on people with ADHD and their brain activity, we still can’t diagnose ADHD by using a brain scan. As professor Katya Rubia explains to Rory Bremner, differences in the brains of people with ADHD, compared to those without ADHD, can be seen when you average over large groups (see figure below). For instance, children with ADHD have smaller brain structures in the frontal parts and in deeper areas of the brain (the basal ganglia). These regions are also known to be less activated in children with ADHD, when they need to inhibit a response. As an example, in the documentary Rory Bremner finds it very difficult to inhibit his comments about Katya Rubia’s accent and beauty. This could be due to under activation of his frontal brain and basal ganglia. However, the MRI findings are only based on averages, and can be very different for individual people. Just like that you can’t tell if someone is a man or a women just by measuring their length – even though men on average are taller than women – you can’t tell if someone has ADHD by just looking at their brains.

Meta-analysis of structural MRI studies in ADHD
Differences in brain structure between children with ADHD and children without ADHD. Results are averages from a meta-analysis of 27 studies. Yellow areas indicate decreased volumes in ADHD children compared to children without ADHD. From the study by Norman and colleagues, in JAMA psychiatry, 2016.

 

Fruit flies and ginger bread men

So why does someone have ADHD? Are you born with ADHD? Is it the fault of your parents? Or should we blame society? Extensive research has shown that there is a strong genetic component to ADHD. This means that you inherit the risk for developing ADHD from your parents – even when they don’t raise you, as for instance in the case of adoption. Professor Andreas Reif describes that there are hundreds or even thousands of genes that can contribute to ADHD. Each single gene by itself will not cause ADHD, but together they contribute to the risk for ADHD. The situation with the genes is therefore similar as to that of the brain scans: no gene test can prove that you have ADHD as there is too much variation between individuals. So why should we put time and money in investigating the genetics of ADHD?

For one thing, if we understand which combination of genes contributes to a high risk for developing ADHD, screening could help in early detection of those at risk. For instance, ADHD is known to often co-occur with other disorders, such as depression, substance abuse or obesity. If we know who is at risk of developing such a secondary disorder, the person can be informed about the importance of behavioural adaptations that reduce this risk, such as regular exercise in the case of obesity. Another reason is that better understanding of causal mechanisms can aid in developing new treatments for ADHD.

In order to study these causal mechanisms, professor Barbara Franke uses fruit flies (drosophila melanogaster). With these flies she can investigate which gene is associated with which specific aspect of ADHD, such as hyperactivity or inattention. In the documentary Barbara Franke shows Rory Bremner how she releases fruit flies in a specially designed maze. At the end of the maze, the fruit flies can find food. The more often they go through the maze, the better they learn the route. But while the flies go through the maze, they are being distracted by a light which they should ignore. For this experiment, some fruit flies have undergone modifications of genes that we suspect to pose risk for ADHD. And it turns out that the ADHD-like flies are more distracted by the lights than the ‘normal’ flies. In this way, we can find out which genes cause increased distractibility.

But it’s not just genes that contribute to ADHD. Although genes explain about 80% of ADHD, environmental influences, such as preterm birth or toxins during pregnancy also contribute to the risk for ADHD [i.e. see this recent post by Stephen Faraone)]. In the documentary, Peter Hill shows Rory Bremner how genetic and environmental factors can contribute to slightly different appearances – also called phenotypes – by baking gingerbread men. Peter and Rory bake several of these cookies, but with slight differences in the ingredients and procedure. One gingerbread man for instance is baked less long, which translates to environmental. The other gingerbread men lack eggs, contain less flour, or have no ginger. These are exemplary of the genetic influences of ADHD. All in all, the gingerbread men still look like gingerbread men – and probably are just as tasty – but knowledge about what happened in the preparation and baking process can help understand why they are different.

Medication & treatment

As mentioned earlier, ultimately we hope that a better understanding of ADHD enables better treatment. At the moment, psychostimulant medication, such as Ritalin and Concerta, is the most widely used form of treatment. As Andreas Reif explains, methylphenidate (which is the active substance in Ritalin) increases the availability of dopamine and noradrenaline in the brain. These two substances are necessary for a wide range of cognitive tasks, including learning, paying attention and inhibiting responses. In people with ADHD there seems to be too little dopamine available, which is why they benefit from this medication. Rory Bremner tries it for the first time in the documentary, just before he gives a comedy show. He describes the effect as “It’s a bit like someone switched my brain from techno radio 1 to classic fm”. However, as professor Phillip Asherson tell us, although this medication can help you to focus, some people will feel more nervous or restless. In that case, the medication doesn’t work for them.

Alternative forms of treatment are also being tested, such as neurofeedback. Friederike Blume from Tübingen shows Rory Bremner how she uses EEG (measuring electric signals in the brain by using a device that looks like a swim cap) combined with virtual reality in order to train people to improve their neural signals. Similar to going to the gym, regular neurofeedback training may help to improve brain functioning and hence reduce symptoms.

And what happens when ADHD is left untreated? In some cases, not so much. Rory Bremner was never diagnosed with ADHD, even though in the documentary he finds out that he does have all the symptoms of ADHD. For a comedian as himself, an impulsive and associative mind is very beneficial. However, for others, untreated ADHD can cause big problems. About 30% of the offenders in prison has ADHD, and most of them have not received treatment. As most of these offences concern impulsive offences, such as spraying graffiti, medication can help to prevent such behaviour.

So, what have we learned?

All in all, both the documentary and the newspaper article give us an idea of what the research on ADHD is all about: from fruit flies to brain scans, researchers are trying to discover the biology of ADHD. As Andreas Reif puts it, better knowledge and diagnostics of ADHD, in all stages of life, can greatly improve detecting and treating ADHD. And this can greatly improve quality of life of those with ADHD. That’s what inspires us to do the research.

This post was written by Jeanette Mostert. Jeanette is Dissemination Manager of the CoCA project.