Breaking Down the Risks: Seizures and Brain Bleeds in Familial Cavernous Malformation

Published on August 20, 2025 Posted in Current News & Updates

Research articles can sometimes feel overwhelming with medical terms and statistics. We’ve created this summary to highlight the key findings in clear, everyday language so you can better understand what this study means for people with familial cavernous malformation. The original article, “Lifetime Risk of First Symptomatic ICH or Seizure in Familial Cerebral Cavernous Malformations: A Multicenter Patient Data Analysis”, is available here if you’d like to read more.

This paper, published in the influential journal Neurology, provides the most detailed picture yet of how familial cavernous malformations progress over a lifetime. It highlights the importance of ongoing monitoring and care for people with familial CCM and shows that genetic testing can help identify those at higher risk. While the study mainly included patients treated at specialized centers and relied on retrospective records, it offers valuable insights that can:

  • Help patients and doctors make informed decisions about management and follow-up.
  • Assist researchers who are planning clinical trials in developing better trial designs.
  • Justify research funding for CCM, as the paper makes clear that familial CCM is not a benign disease.

Familial cavernous malformations are clusters of abnormal blood vessels in the brain or spinal cord that can run in families. These lesions carry a lifelong risk of bleeding (called symptomatic hemorrhage) and seizures, but until recently, it wasn’t clear how likely these events are over a person’s lifetime. To better understand these risks, this study looked at over 1,500 people with familial cavernous malformation from 16 medical centers around the world and the Alliance to Cure Cavernous Malformation. (A big thanks to our members who participated in the BVMC study.) Researchers examined medical records, brain imaging, and genetic testing, and followed patients over many years.

The study found that about 55% of patients experienced at least one bleed, and 28% had at least one seizure. Over a lifetime, for patients with familial CCM, the risk of having a first symptomatic bleed is around 80%, while the risk of a first seizure is about 45%. Bleeds and seizures tended to occur at a consistent rate after age 20. Genetic testing showed that people with CCM3 variations had a more aggressive disease course, meaning they were more likely to experience bleeding than those with CCM1 or CCM2 variations. Experiencing a bleed or seizure was also linked to worse overall neurological function later in life.

This study is a true example of international collaboration. Researchers from across the globe came together to share knowledge and patient data, making this one of the largest efforts to better understand cavernous malformation. We are deeply grateful to the consortium and all the researchers who contributed to this critical study.

The study authors are shared below by country to demonstrate how far-reaching this research was.

Argentina

  • Andrés Cervio

  • Facundo Villamil

  • Julieta Rosales

China

  • Da Li

  • Zhen Wu

  • Jian-Cong Weng

France

  • Hugues Chabriat
  • Stéphanie Guey
  • Dominique Herve

Germany

  • Philipp Dammann

  • Alejandro N Santos

  • Laurèl Rauschenbach

  • Christoph Riess

  • Marvin Darkwah Oppong

  • Hannah Karadachi

  • Yahya Ahmadipour

  • Karsten H Wrede

  • Ramazan Jabbarli

  • Cornelius Deuschl

  • Yan Li

  • Martin Köhrmann

  • Benedikt Frank

  • Matthias Rath

  • Robin A Pilz

  • Ute Felbor

  • Ulrich Sure

  • Laven Mavarani

  • Börge Schmidt

Italy

  • Antonio Petracca

  • Carmela Fusco

  • Leonardo D’Agruma

  • Marco Castori

Spain

  • Manou Overstijns

Switzerland

  • David Bervini

  • Johannes Goldberg

  • Andreas Raabe

  • Thomas Wälchli

  • Jürgen Beck

  • Christian Fung

United Kingdom

  • Rustam Al-Shahi Salman

United States

  • Jacob Croft

  • Mellisa Renteria

  • David Jang

  • Jun Zhang

  • Gary K Steinberg

  • Jeanne Gu

  • Guilherme Santos Piedade

  • Kelly D Flemming

  • Giuseppe Lanzino

  • Atif Zafar

  • Shantel Weinsheimer

  • Jeffrey Nelson

  • Joseph M Zabramski

  • Amy Akers

  • Leslie Morrison

  • Charles E McCulloch

  • Helen Kim

  • Brain Vascular Malformations Consortium Investigators