Viktor H. Ahlqvist

Fantastic work by @pmadleydowd.bsky.social ! If you're into multiple imputation - look this way

Have you ever tried to implement multiple imputation with several incomplete variables? How do you know whether MI will be valid for your data? We have just published an easy to use algorithm using modifications to DAGs (now they're colourful) to aid decision making with MI
doi.org/10.1093/aje/...

Paracetamol use during pregnancy not linked to autism, our study of 2.5 million children shows Our research provides strong evidence against the concerning claims made recently by US president Donald Trump.

theconversation.com/paracetamol-...

Cheers 😂

Going for top read 2025 too

#episky #ispe #pharmacoepi

Trump links autism and Tylenol: is there any truth to it? The US president calls the widely used painkiller, also known as paracetamol, ‘a very big factor’ in autism, but scientists say that strong evidence is lacking.

I provided some comments on the #paracetamol and #autism debacle in Nature:
www.nature.com/articles/d41...

#episky #sibsky

@danielberglind.bsky.social @pmadleydowd.bsky.social and more @ki.se @au.dk

Moving beyond risk ratios in sibling analysis: estimating clinically useful measures from family-based analysis Objective: Findings from family-based analyses, such as sibling comparisons, are often reported using only odds ratios or hazard ratios. We demonstrate how this can be improved upon by applying the ma...

For those of you using sibling analysis, perhaps you'll find this useful 🥳: www.medrxiv.org/content/10.1...

Thank you, Magda! 🎉🎉 This will enable even more synergies between us!

Thanks mate ! Would not have been possible without your help and support!

Safer medications for pregnant women and children Viktor H. Ahlqvist, postdoc at the Institute of Environmental Medicine (IMM), receives 3,000,000 SEK in a Postdoctoral Grant from the Swedish Society for Medical Research (SSMF) for the project “Advan...

Fantastic news! This is entirely attributable to all my colleagues—everyone from mentors to students—who have made this possible🎉🎉

news.ki.se/safer-medica...

Hey hey hey. All for the CV mate

Loool! Perhaps they are relying on scholar rather than their own publisher link? 😂

Doing multiple imputation? Do your auxiliary variables also have missing?! Check out this brilliant paper by Paul et al.

#episky

as would larger cohorts with deep phenotyping, ideally including genetics; I am deeply concerned about genetic confounding, considering the known genetic overlap between both psychiatric and epileptic indications and neurodevelopmental outcomes!

And yes, I definitely agree that there is likely residual confounding despite controlling for observed indications and SES. Better data on siblings would be incredibly useful, ...

Yes, they were independent of the original safety signals. Lamotrigine has been estimated to not be associated with malformations or neurodevelopmental outcomes in a series of cohorts.

It’s all quite challenging. However, we believe we’ve identified some consistent signals for valproate (expected), topiramate (verification of prior findings), and carbamazepine (novel). Whether these hold up under further causal scrutiny remains to be seen...!

We tried to adjust for many of these imbalances (inc bipolar indication), but the coverage & quality of the registry data have limitations. This is partly why sibling comparisons are valuable, assuming indications remain somewhat stable across pregnancies (this may not hold for episodic conditions).

However, it’s not ideal. As you noted, lamotrigine is also used for bipolar (and on/off-label elsewhere). Also, individuals with more 'severe indications' (e.g., generalized epilepsies) are often treated with e.g. topiramate, introducing differential indication severity even within antiseizure meds.

Re Lamotrigine: It is first-line treatment for epilepsy and is generally considered the safest option during pregnancy (not linked to malformations). Using it as a reference, rather than ‘no use,’ has clear advantages – and this approach has been used in the teratology literature.

Thanks for the interest, @sebatlab.bsky.social ! Agree that the sibling analysis shows (much) attenuation. However, we’re cautious about overinterpreting the statistical null given our limited power. Still, we believe this highlights the value of such analyses and the promise as samples grow larger.

Great end-of-year news (yes, I'm bragging—but I can't hold back my excitement over this team effort): Our paper on acetaminophen safety was one of the most popular in *JAMA* this year! jamanetwork.com/journals/jam...

#EpiSky

New research out on antiseizure medications in pregnancy 🎉🎉
Nature Communications: nature.com/articles/s41...
Thread follows 🧵 🧵:

Should probably tagg #EpiSky - god I've missed epitwitter

@pmadleydowd.bsky.social @draipsych.bsky.social @karolinskainst.bsky.social @aarhusuni.bsky.social @neilmdavies.bsky.social @danielberglind.bsky.social .. and many more... 🥳 @natureportfolio.bsky.social

a man with a mustache is wearing a blue jacket and a leopard print shirt . ALT: a man with a mustache is wearing a blue jacket and a leopard print shirt .

This work was a real team effort—it took almost a decade to complete, and we’re thrilled to see it out in the world today. We hope it sparks important discussions and helps improve safety recommendations for these vital medications.