TOPLINE:

One third of patients with untreated cerebral cavernous malformations (CCMs) experienced epileptic seizures, with the risk for recurrence being lower among those on antiseizure medications after the first event. Most patients with CCM‑related epilepsy achieved seizure freedom at 2 and 5 years, with most being on antiseizure medication monotherapy.

METHODOLOGY:

• Researchers conducted a prospective population-based cohort study of 300 adults (median age, 44 years; 53% women) in Scotland who were newly diagnosed with CCMs during 1999-2003 or 2006-2010 using brain MRI or pathology.
• Participants were followed up for a median duration of 15 years.
• The incidence and risk factors for epileptic seizures, including seizures after initial presentation, first‑ever seizures, recurrence following a first unprovoked event, and attainment of seizure freedom, were evaluated during the long-term follow‑up without CCM intervention.

TAKEAWAY:

• Overall, 98 (33%) patients experienced epileptic seizures after any presentation, of which 89 were definitely related to CCMs; younger age (adjusted hazard ratio [aHR], 0.82 per 10-year increase; P = .008) and initial presentation with epileptic seizures (vs incidental; aHR, 12.94; P < .001) were independent risk factors.
• The risk for a first-ever epileptic seizure definitely or possibly related to CCMs was 6% over 10 years.
• Following the first unprovoked epileptic seizure, the 10-year risk for recurrence was 80%; the initiation of antiseizure medication was associated with a lower risk for the recurrence of epileptic seizures definitely or possibly related to CCMs (aHR, 0.36; P = .003).
• Among patients with CCM-related epilepsy, 82% and 62% were seizure free at 2 and 5 years, respectively; most were on antiseizure medication monotherapy.

IN PRACTICE:

"Clinicians may use the findings from this study to inform patients with CCM about their risk of a first-ever epileptic seizure, the subsequent risk of seizure recurrence, and the chance of becoming seizure-free," the authors wrote.

SOURCE:

This study was led by Abel Clemens Adriaan Sandmann, Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands. It was published online on November 13, 2025, in Neurology.

LIMITATIONS:

The study may have missed some events due to the reliance on routine records and questionnaires, and some episodes may have been misclassified as epileptic seizures as they can be difficult to distinguish from migraine aura.

DISCLOSURES:

This study was supported by grants from the Medical Research Council, the Chief Scientist Office of the Scottish Government, and the Stroke Association. Some authors reported receiving financial support or institutional educational grants from various organisations and pharmaceutical companies.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.