EEG shows which treatment will help
Children and adults who are diagnosed with ADHD often receive behavioral therapy initially to help them cope with their condition. Whether or not in combination with medicines such as methylphenidate (for example Ritalin) or dexamfetamine. But not all people with ADHD have an effect on medication. Unfortunately, they don’t know this until they take the drugs. But good news for people with ADHD: In the near future, brain research may reveal whether and which drugs for ADHD will work.
HealthNet asks Martijn Arns five questions. He obtained his doctorate at Utrecht University in December 2011 on research ‘Personalized medicine in ADHD and depression’.
1. What exactly did you research?
In our study, we investigated whether there are differences based on brain activity (in this case the electrical brain activity or the EEG) between patients who do or do not respond to a treatment such as antidepressants, rTMS, methylphenidate or neurofeedback in order to be able to assess on that basis. predict who will and who will not respond to a particular treatment.
2. Will it be possible in the future to see on an EEG whether someone has ADHD?
No, it is not possible to make a diagnosis based on the EEG. This is only possible with epilepsy or sleeping problems. This is because the definitions “ADHD” and “depression” only include behavior. Therefore, the diagnosis will always be based on behaviour. An important question for the future is whether this is useful. It would be nice if a ‘diagnosis’ had predictive value for the right treatment, at the moment this is not the case. That is why the possibilities for the EEG lie more in being able to predict what the right treatment is.
3. Why are medicines effective for some people with ADHD and not for others?
At the moment not enough is known to be able to answer that question exactly. However, there seem to be a number of subgroups of ADHDers. The largest group (50-75 percent) is characterized by an EEG with too much ‘slow’ activity characteristic of a reduced alertness level. Everyone shows this activity at the end of the day when we are tired. Children with ADHD show this all day long. This also explains why psychostimulants such as methylphenidate work by making children ‘more alert’. The cause of the problems in this sub-group is believed to arise from subtle sleep problems such as a shifted sleep-wake rhythm that causes children to fall asleep later. Sleep apnea or Restless Legs Syndrome can also be a cause in some cases. Treatment in this sub-group should therefore focus more on sleep problems. Treatments such as melatonin and neurofeedback show promise in this regard. In the case of more serious sleep problems such as sleep apnea or Restless Legs Syndrome, further investigation at a sleep clinic is needed.
4. And you also found a sub-group that did not respond to treatment at all?
Yes, an important other sub-group shows a so-called ‘delayed alpha peak frequency’. These people appear not to respond to any treatment. We have found these in both ADHD and depression. This measure (also called a biomarker) can be used to develop new treatments for this subgroup.
5. What will change and what are the benefits for people with ADHD?
Because we gain more insight into which subgroups do and do not respond to different treatments, we also gain more insight into the cause of the symptoms of ADHD. As in the example above, this can lead to a different perspective so that new treatments can be further developed that intervene more directly in the underlying cause, such as sleeping problems. Furthermore, measures that currently predict a person will not respond can also be further used to develop a new treatment for those sub-groups.
Martijn Arns is currently working on a large-scale international study, the so-called iSPOT study in ADHD and Depression. For this study they are still looking for many patients with ADHD or depression to participate. For more information see also: www.brainclinics.com/ispot
