June 4, 2023

You’ve probably heard before that acetaminophen during pregnancy is associated with symptoms of ADHD and Autism in offspring. Well, we’ve got another study on that association. In today’s episode, we examine that study and revisit why we need to be cautious with observational data.

We’ve got another study out on the association between acetaminophen during pregnancy and the risk of attention deficit hyperactivity disorder and autism and offspring as usual most media headlines aren’t presenting this as the observational study that it is and are instead resorting to headlines that don’t include the kind of nuance necessary to understand the results

In a real world context so we’ll do it for them that’s the topic of this week’s healthcare triage studies on the association between acetaminophen during pregnancy and the risk of adhd and autism and offspring are nothing new a 2014 study in jama pediatrics reported the prenatal exposure to acetaminophen was associated with a higher risk of adhd like behaviors at

Seven years of age a 2016 study reported an association between prenatal acetaminophen and symptoms of autism and male offspring and adhd symptoms in both male and female offspring and the list goes on up to the most recent study published in may of this year but before we get to that one let’s stop and remember some very important things starting with how common

The exposure and the outcome are here what i mean by that is that lots of pregnant women take acetaminophen it’s one of their only options for pain relief and we see lots of adhd and autism diagnoses among children it’s not like we’re seeing a very small subset of pregnant women taking acetaminophen and then just their small subset of children exhibiting symptoms

Of these disorders all of these studies rely on the parent remembering when and how much acetaminophen they took during pregnancy and we know that data like these are notoriously unreliable and third all these studies are observational meaning they are only reporting an association between two things not a causal relationship that immediately requires skepticism

Because there are a bunch of factors that could be causing the outcome of interest which in this case is adhd or autism we’ve used the shark and ice cream example before to illustrate this say that some observational data suggests that people consuming ice cream at the beach also appear to be at higher risk of being attacked by a shark we could rile up the public

And grab some clicks by reporting this association as a potential danger of ice cream maybe sharks love ice cream so if you eat it they’re likely to find you more tasty or we could investigate further and realize that while these two things are associated the actual factor causing both of them is that hot summer temperatures drive people to the beach where they

Will eat ice cream and perhaps swim in the ocean where the sharks live that is a simple and pretty obvious example but it applies the same to today’s topic any number of underlying factors could be responsible for increasing acetaminophen consumption and offspring adhd or autism causing both to rise but not because one caused the other a group of pregnant people who

Took acetaminophen during pregnancy probably have a lot of differences from a group of pregnant people who did not for example perhaps people in the group who took it had some kind of pain or illness that could easily affect offspring outcomes in that case it could be the illness that increased symptoms of adhd or autism in their children not the acetaminophen but

Finally to the current research the most recent study in associated headlines this was actually a meta-analysis of six european studies examining the association between prenatal acetaminophen and autism or adhd outcomes among offspring the authors concluded the prenatal acetaminophen exposure increased the likelihood of both disorders by about 20 that sounds like

A lot at first glance but keep in mind that this is not 20 percentage points as dr emily oster pointed out in her analysis of the study this would translate to an increase in risk from four to five percent if the baseline risk were four percent dr ostra also pointed out some of our usual complaints about these types of studies along with some more specific ones for

Example she notes the groups with the highest rates of prenatal acetaminophen exposure actually displayed lower rates of adhd which is totally contrary to the whole hypothesis here our critical take on these studies doesn’t mean that we’ve ruled out issues with acetaminophen it just means that we think the evidence is too weak to get worked up about right now the

Data we have so far tell us that we really need some high quality studies to understand this very important issue and while parents will need to make their own calls here our opinion is that currently the benefits of maternal pain relief outweigh the potential for adverse offspring outcomes hey you enjoyed this episode you might enjoy this other episode on covet

Variants and vaccines we’d appreciate it if you’d like this video and subscribe to the channel and consider going to patreon.com healthcare triage where you can help support the show and make it bigger and better even during a global pandemic we’d like to especially thank our research associates james glasgow and joe sevitz and of course our surgeon admiral sam you

Transcribed from video
Relative Risks of Acetaminophen, ADHD, and Autism By Healthcare Triage