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Observational Study
. 2024 Jun;65(6):1698-1708.
doi: 10.1111/epi.17969. Epub 2024 Mar 30.

Prescribing patterns for higher dose folic acid in pregnant women with epilepsy treated with antiseizure medication

Håkon Magne Vegrim  1 , Julie Werenberg Dreier  1   2 , Jannicke Igland  3   4 , Nils Erik Gilhus  1   5 , Silje Alvestad  1   6 , Mika Gissler  7   8 , Maarit K Leinonen  7 , Yuelian Sun  9 , Helga Zoega  10   11 , Jakob Christensen  2   12   13 , Marte-Helene Bjørk  1   5   14 , Torbjörn Tomson  15
Affiliations
Observational Study

Prescribing patterns for higher dose folic acid in pregnant women with epilepsy treated with antiseizure medication

Håkon Magne Vegrim et al. Epilepsia. 2024 Jun.

Abstract

Objective: This study was undertaken to characterize the use of higher doses of folic acid (≥1 mg daily) in relation to pregnancy in Denmark, Norway, and Sweden in women with epilepsy treated with antiseizure medication (ASM).

Methods: In this observational study, we used data from national medical birth, patient, and prescription registers in Denmark, Norway, and Sweden to retrospectively identify pregnancies in women with epilepsy treated with ASM from 2006 to 2017. The proportion of higher dose folic acid supplementation in pregnancies among women receiving ASM for epilepsy was calculated according to country of origin, time period, and type of ASM. Logistic regression with restricted cubic splines was used to model country-specific time trends.

Results: Among a total of 2 748 882 pregnancies, we identified 8695 (.3%) pregnancies after restricting the population to women with ASM-treated epilepsy. A prescription for higher dose folic acid was filled in 4719 (54.3%) of these pregnancies. The proportion supplemented with higher dose folic acid was highest in Sweden (74.3%) and lower in Norway (41.4%) and Denmark (34.3%). Furthermore, we observed a decreasing trend of higher dose folic acid use in Denmark and Norway from year 2012 to 2017. Among those who used higher dose folic acid, 42% did not start preconception supplementation with higher dose folic acid.

Significance: Supplementation with higher dose folic acid occurred in approximately half of pregnancies in women with ASM-treated epilepsy, with many not starting supplementation until after becoming pregnant. Considerable variability was observed in the use of higher dose folic acid across the countries, despite similar population characteristics and health care systems. Future guidelines should be simplified with clear recommendations developed in a collaborative manner by relevant specialists including neurologists, obstetricians, pediatricians, and public health specialists to enhance real-world applicability.

Keywords: antiseizure medication; epilepsy; folic acid; pregnancy; prenatal care.

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REFERENCES

    1. Tomson T, Battino D, Bromley R, Kochen S, Meador K, Pennell P, et al. Management of epilepsy in pregnancy: a report from the international league against epilepsy task force on women and pregnancy. Epileptic Disord. 2019;21(6):497–517.
    1. Global Burden of Disease Epilepsy Collaborators. Global, regional, and national burden of epilepsy, 1990‐2016: a systematic analysis for the global burden of disease study 2016. Lancet Neurol. 2019;18(4):357–375.
    1. Tomson T, Battino D, Bonizzoni E, Craig J, Lindhout D, Sabers A, et al. Dose‐dependent risk of malformations with antiepileptic drugs: an analysis of data from the EURAP epilepsy and pregnancy registry. Lancet Neurol. 2011;10(7):609–617.
    1. Dwyer ER, Filion KB, MacFarlane AJ, Platt RW, Mehrabadi A. Who should consume high‐dose folic acid supplements before and during early pregnancy for the prevention of neural tube defects? BMJ. 2022;377:e067728.
    1. Kishi T, Fujita N, Eguchi T, Ueda K. Mechanism for reduction of serum folate by antiepileptic drugs during prolonged therapy. J Neurol Sci. 1997;145(1):109–112.

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