Prevalence of epilepsy: a population-based cohort study in Denmark with comparison to Global Burden of Disease (GBD) prevalence estimates

Jakob Christensen; Betina B Trabjerg; Ryan G Wagner; Charles R Newton; Churl-Su Kwon; Kari Modalsli Aaberg; Eugen Trinka; Samuel Wiebe; Judith Helen Cross; Håkon Magne Vegrim; Theo Vos; Jaimie Steinmetz; Julie Werenberg Dreier

doi:10.1136/jnnp-2024-334547

Prevalence of epilepsy: a population-based cohort study in Denmark with comparison to Global Burden of Disease (GBD) prevalence estimates

J Neurol Neurosurg Psychiatry. 2024 Nov 27:jnnp-2024-334547. doi: 10.1136/jnnp-2024-334547. Online ahead of print.

Authors

Jakob Christensen^{1

2}, Betina B Trabjerg^{3

4}, Ryan G Wagner⁵, Charles R Newton^{6

7}, Churl-Su Kwon⁸, Kari Modalsli Aaberg⁹, Eugen Trinka^{10

11

12}, Samuel Wiebe¹³, Judith Helen Cross¹⁴, Håkon Magne Vegrim¹⁵, Theo Vos¹⁶, Jaimie Steinmetz¹⁶, Julie Werenberg Dreier^{3

4}

Affiliations

¹ Department of Clinical Medicine, Aarhus University, Aarhus, Denmark [email protected].
² Department of Neurology, Aarhus University Hospital, affiliated member of EpiCARE, Aarhus, Denmark.
³ National Centre for Register-Based Research, Aarhus Business and Social Sciences, Aarhus University, Aarhus, Denmark.
⁴ Centre for Integrated Register-Based Research (CIRRAU), Aarhus University, Aarhus, Denmark.
⁵ MRC/Wits Rural Public Health and Health Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences University of the Witwatersrand, Johannesburg, South Africa.
⁶ KEMRI-Wellcome Trust Collaborative Programme, Kilifi, Kenya.
⁷ Department of Psychiatry, University of Oxford, Oxford, UK.
⁸ Department of Neurology, Neurosurgery, Epidemiology, and the Gertrude H. Sergievsky Center, Columbia University, New York, New York, USA.
⁹ National Center for Epilepsy, Oslo University Hospital, Oslo, Norway.
¹⁰ Department of Neurology, Christian-Doppler University Hospital, Paracelsus Medical University, Centre for Cognitive Neuroscience, Member of EpiCARE, Salzburg, Austria.
¹¹ Neuroscience Institute, Christian-Doppler University Hospital, Paracelsus Medical University, Centre for Cognitive Neuroscience, Salzburg, Austria.
¹² Institute of Public Health, Medical Decision-Making and HTA, UMIT - Private University for Health Sciences, Medical Informatics and Technology, Hall in Tyrol, Austria.
¹³ Department of Clinical Neurosciences and Hotchkiss Brain Institute, Cummings School of Medicine, University of Calgary, Calgary, Alberta, Canada.
¹⁴ Great Ormond Street Institute of Child Health, University College London, London, UK.
¹⁵ Department of Clinical Medicine, University of Bergen, Bergen, Norway.
¹⁶ Institute for Health Metrics and Evaluation, University of Washington, Seattle, Washington, USA.

PMID: 39532519
DOI: 10.1136/jnnp-2024-334547

Abstract

Background: The Global Burden of Disease Study (GBD) produces prevalence estimates for 'idiopathic epilepsy' (ie, of unknown aetiology) and 'secondary epilepsy' (ie, with known aetiology) but does not report prevalence by underlying aetiologies for 'secondary epilepsy'.

Methods: We used nationwide, population-based register data from Denmark to identify underlying causes of epilepsy and their contribution to prevalence of 'secondary epilepsy' and compared with global prevalence data from GBD 2019. We identified all persons with a hospital-based epilepsy diagnosis and a filled prescription for antiseizure medication between 1 January 2009 and 31 December 2018. Epilepsy was categorised into 'idiopathic' or 'secondary' and 'total epilepsy' as the sum of the two epilepsy categories.

Results: On 31 December 2018, a total of 5 784 284 individuals (49.7% males) were living in Denmark including 40 336 with epilepsy (51.5% males). Perinatal conditions, traumatic brain injury, brain tumours and stroke were prominent underlying causes of 'secondary epilepsy'. The prevalence of 'total epilepsy' in Denmark was 697 (95% CI 691 to 704) per 100 000 population (264 (95% CI 260 to 269) for 'secondary epilepsy' and 433 (95% CI 428 to 438) for 'idiopathic epilepsy'). In the GBD 2019 Study, the prevalence of 'total epilepsy' in 2018 was 682 (95% uncertainty interval (UI) 586 to 784) per 100 000 population (359 (95% UI 324-397) for 'secondary epilepsy' and 324 (95% UI 249 to 404) for 'idiopathic epilepsy').

Conclusions: Prevalence estimates of 'total epilepsy', 'idiopathic epilepsy' and 'secondary epilepsy' in Denmark align with the GBD 2019 estimates. In future studies, it is suggested to explicitly include all types of epilepsy, including 'secondary epilepsy', which is currently estimated as sequelae (consequences) of underlying diseases.

Keywords: DEMENTIA; EPIDEMIOLOGY; EPILEPSY; STROKE.