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Causes of epilepsy



of people there is no known cause

Approximately 65% of people do not know the reason for their epilepsy. This is known as ‘idiopathic epilepsy’.

Different types of epilepsies have different causes, but in 65% of cases, the cause is not known. This is called ‘idiopathic epilepsy’. Treatment pathways for people with idiopathic epilepsy can be complex.

For the remaining 35% of cases, some of the common causes contributing to the development of epilepsy include:

Either an inherited genetic tendency or a change or genetic mutation in a person’s genes can cause some types of epilepsy. Part of the genetic likelihood of developing seizures is called a seizure threshold. It’s thought that around one in three people with epilepsy have a family member with the condition and that it’s a propensity to a low seizure threshold which leads to the development of epilepsy, rather than inheriting epilepsy itself.

When the brain has been injured, the brain’s structure or function might be altered causing abnormal electrical activity. Infection, such as meningitis or encephalitis, or stroke or oxygen deprivation can also cause scarring on the brain leading to seizures. Brain tumours and neurodegenarive diseases such as Alzheimer’s may also cause epileptic seizures.

There are also autoimmune disorders which affect multiple organ systems and frequently involve inflammation of the central nervous system, in which seizures are a core symptom.

Structural is when there is a distinct abnormal structural cause present in the brain that is known to substantially increase the risk of seizures. This can be a congenital cause that a person is born with or can have a genetic component. These structural abnormalities often cause drug resistant epilepsy. Most of these causes can be seen on imaging of the brain with an MRI.

Seizure Triggers

Epilepsy can be provoked by certain events, called seizure triggers. These vary from person to person. Common seizure triggers include:

  • Flashing lights

For around 3% of people, flashing lights or patterns can trigger seizures in people with photosensitive epilepsy. This jumps to 30% of young people (typically aged between 12 and 16) with juvenile myoclonic epilepsy who are photosensitive. The majority of these will grow out of it in their 20s.

  • Missed medications or not taking medication as prescribed
  • Feeling tired and lack of sleep
  • Stress
  • Alcohol and recreational drugs

Our Research Roundtable

For the majority of people where no clear cause is present, treatment pathways can be complex

The research projects and fellowships we support are of the highest scientific merit and are subject to rigorous scrutiny, involving a Scientific Advisory Committee, independent expert opinion, interviews and peer review. Our pioneering clinical research discovers ways to advance the medical care and management of people living with epilepsy and our lab-based scientific projects investigate causes and methods for improved diagnosis, treatment and prevention. We aim to provide help for today and hope for tomorrow.

Alongside developing the next generation of epilepsy research leaders, we play a key role in capacity building the research community. Our internationally renowned Expert Workshop programme and dissemination activities aim to forge local and global collaborations. We also accelerate innovations that improve clinical practice and health policy through partnership working and advocating for further investment in research.

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