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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...

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...

news.ki.se

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Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Mar 19

Hey hey hey. All for the CV mate

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Mar 19

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

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Feb 19

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

#episky

Paul Madley-Dowd @pmadleydowd.bsky.social · Feb 19

Final version published so time to talk about it: doi.org/10.1093/aje/...

When using multiple imputation to account for missing data we often use auxiliary variables (variables included in the imputation model but not the analysis model) to 1) reduce bias and 2) improve statistical efficiency.

Analyses using multiple imputation need to consider missing data in auxiliary variables

Abstract. Auxiliary variables are used in multiple imputation (MI) to reduce bias and increase efficiency. These variables may often themselves be incomple

doi.org

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Jan 11

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!

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Jan 11

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, ...

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Jan 11

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.

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Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Jan 6

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...!

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Jan 6

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).

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Jan 6

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.

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Jan 6

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.

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Jan 6

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.

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Dec 17

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

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Reposted by Viktor H. Ahlqvist

Viktor H. Ahlqvist @ahlqvistviktor.bsky.social · Nov 20

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

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