Headlines are designed to grab your attention. Recent headlines about Adderall and other ADHD medications are scary. This is another example of media misinterpreting a study with the headline. I’ve written before about Adderall being misrepresented by headlines.
In this post I will generally refer to stimulants by their common names. Adderall is in the amphetamine family and as used here could include other named medications in that family. Ritalin is in the methylphenidate family and as used here includes other medications in its family.
That sounds like a typical headline. It’s eye-catching, right? It won’t be something you forget if you take Adderall or are considering starting it.
If these medicines have been working well for you and you aren’t hearing or seeing things, you don’t need to stop them.
How can I say that? Am I not worried about someone becoming psychotic?
We always need to look at studies critically. The title of an article, or even the summary, can be misleading. Attempt to read the study itself, but if you are unable to, find a summary by an expert in the field.
Limitations in the study
This study actually fares well in many of the above things to consider when evaluating a study. It’s a respected journal and there’s a large sample size, but it’s not a double blind controlled study. It’s a review of insurance codes. This can be fraught with many problems.
The study was a review of codes from national insurance claim data. It included teens and young adults who were starting these medicines for the first time. They reviewed codes for diagnoses as well as prescriptions. They did not have any direct study of the patients. Anyone who was doing well on these medications already was excluded.
Unable to accurately assess disqualifiers
Anyone who had filled a prescription for a stimulant in the year prior to the study was disqualified. That means the many, many people who use stimulants with great benefit for years were not included. There is no comparison to total number of prescriptions for this.
We know that many people will self medicate with someone else’s medicine. There was no way to assess if they used someone else’s prescription medication, so there could be misrepresentation of new medication starts in the study population. This means even one of their qualifying conditions cannot be verified.
Inability to assess if patients accurately took medicine
We all know that people will fill prescriptions that they don’t take as directed.
There is no way to tell from this study design if the patients took their medicine regularly, or even at all.
Adderall has a larger street value than ritalin, so if more of the patients who were prescribed adderall diverted their medicine to someone else, they were still included in the psychosis number. This could sway the numbers making adderall look more problematic than ritalin because they weren’t being medicated. Said in another way: if people are more likely to take their medicine, they’re less likely to have psychosis.
This is just a thought. I have no way of knowing this information based on the study design. I include it because this is the way we must evaluate study results. We need to consider the results and other possibilities and explanations critically.
What does double the risk really mean?
The age range studied is one at which schizophrenia and other psychoses tend to develop.
They compared psychosis rates to people treated with methylphenidates versus amphetamines and found the risk was double in those starting amphetamines. Double sounds huge, but it was still very small numbers.
One big problem is that there was not a comparison to a baseline development of psychosis in people of the same age not on medication.
We would expect a small number of study participants to develop psychosis, whether they start the medicine or not. They did not attempt to compare this with their study population.
Incidence estimates of new psychosis in the general population in one study showed 126 per 100,000 among those aged 15 to 29. This means that about 0.12% of people are expected to develop psychosis in this age group each year.
Risk of psychosis in those with ADHD
We also know that people with ADHD struggle more with mental health.
Their overall risk of psychosis may be higher, but since they didn’t compare the same age range of people (with and without ADHD) who did not start any new medications during the same time frame, we do not know that baseline.
The recently announced study about new psychosis related to new amphetamine or methylphenidate shows 343 episodes of psychosis among the 221,846 study participants between 13 and 25 years of age. The group of people starting methylphenidate had a 0.10% risk and those on amphetamines had 0.21%.
The age groups in the studies are slightly different. We know that risk increases with age, so it should be further studied if the age range contributed to this difference.
Closer follow up matters
It is also possible that people who are starting a new medicine are more likely to be identified early in their psychosis.
Many adolescents and young adults rarely see physicians or other medical providers since they’re generally healthy. If they aren’t seeing someone who could identify psychosis, they would not get a diagnosis.
People who see someone who is prescribing stimulant medications are hopefully being assessed for mental health in general. It is expected that they are more likely to have problems identified.
This wouldn’t explain the difference between medicated groups, but could raise the incidence overall identified.
This study doesn’t convince me that the risk of psychosis is enough to avoid using it for the management of ADHD. Both amphetamines and methylphenidates have been used successfully in many people over the years.
For more reading
Methylphenidate and the risk of psychotic disorders and hallucinations in children and adolescents in a large health system Transl Psychiatry. 2016 Nov; 6(11): e956.