What is Epilepsy?

WHAT IS EPILEPSY?

Epilepsy, which is sometimes referred to as a “seizure disorder,” is a diverse group of neurological disorders of varying types and severities that are characterized by recurrent seizures. When a person has had two or more seizures more than twenty-four hours apart which have not been provoked by specific events such as a stroke, brain injury, infection, fever, or fluctuations in blood sugar, they are considered to have epilepsy. A person can also be diagnosed with epilepsy if they have one or more unprovoked seizure and a probability of future seizures.

WHAT CAUSES EPILEPSY?

While the exact causes of epilepsy are varied and not entirely known, in general epilepsy and seizures result from abnormal signals from neurons (a type of brain cell) in the brain. It can be genetic, meaning it is the result of mutations in a person’s genes, or it can be acquired through events such as physical injury or infection.¹ In 40% of epilepsy cases worldwide, the cause is idiopathic , which means unknown.^{2, 3}

Some underlying causes of acquired epilepsy include:

• Brain structure abnormalities
• Head trauma
• Infectious disease
• Stroke
• Tumors

HOW COMMON IS EPILEPSY?

• 1 in 26 Americans will develop epilepsy in their lifetime. ⁴
• An estimated 3.4 million Americans and 65 million people worldwide currently live with epilepsy. ⁴
• Each year more than 150,000 people are diagnosed with epilepsy. ⁴
• An estimated 470,000 children in the US live with epilepsy; approximately one in 150 children is diagnosed with epilepsy. ⁵,⁶
• Epilepsy affects more people than multiple sclerosis, cerebral palsy, Parkinson’s disease, and ALS combined

Epilepsy and seizures can develop in any person and at any age, regardless of their race, ethnicity, or sex; however, having some of the following characteristics may put an individual at a higher risk.

AGE

While epilepsy and seizures can develop in any person at any age, new cases are most common in children, especially in their early years of life. The incidence of epilepsy lessens after childhood but then increases again in older adults (>60 years of age).

Infants in their first year of life are vulnerable to seizures (and epilepsy) because their brains are rapidly developing, with neurons growing and making new connections all the time. For many infants, their brains will develop without disruption; for others, however, they may experience disturbances that can cause epilepsy. This may include head trauma, genetic mutation, or viral infection in the birthing parent during pregnancy.

Neonatal seizures (seizures during the first four weeks of a baby’s life) may be difficult to diagnose because they are subtle and resemble normal movements of a baby, or because some doctors do not have specialized training in epilepsy. A pediatric neurologist can help diagnose neonatal seizures and identify their cause.

Though incidence begins to decrease as an infant’s brain continues to develop, toddlers and young children also develop epilepsy. Most commonly, this age group is susceptible to febrile seizures (seizures associated with fever), but epilepsy can develop from genetic disorders, central nervous system (CNS) infections, developmental disorders, and head trauma.

The incidence of epilepsy decreases during the teenage, early adult, and middle-aged years, but then rises again in adults 60 years of age and older. In this age range, epilepsy can be associated with strokes, Alzheimer’s disease, head trauma, and brain tumors among other things.

RACE AND ETHNICITY

There is limited research available on the incidence of epilepsy across race and ethnicity. There is no direct evidence that a person’s race or ethnicity alone puts them at a higher risk for developing epilepsy; however, there is research to suggest that there are commonalities between people with similar socioeconomic, racial, or ethnic backgrounds.

• The prevalence of active epilepsy was found to be higher in non-Hispanic White Americans and non-Hispanic Black Americans, as compared to Hispanic Americans.⁷
• The prevalence of active epilepsy was higher in Black Americans as compared to White Americans.⁸
• The proportion of people with “unclassifiable” epilepsy was found to be higher in people with African ancestry as compared to whites. The latter finding may be due to the lack of access to diagnostic testing such as prolonged EEG monitoring, making diagnosis difficult and uncertain.⁹
• It is estimated that 1.5% of Asian Americans are living with epilepsy, though more research is needed.¹⁰

It’s important to note that there are disparities in epilepsy care, both in the United States and abroad, which can result in certain ethnicities and races being over or underreported in epilepsy research. This is known as the treatment gap or the mismatch between those who need treatment and those who have access to treatment.

HOW IS EPILEPSY DIAGNOSED AND TREATED

To diagnose epilepsy, medical professionals conduct tests to detect abnormalities in a patient’s brainwaves. Tests can also detect seizure activity, including where in the brain a seizure starts. The most common diagnostic test for epilepsy is the EEG, but other brain scans, like MRI or PET, can also be used depending upon the patient’s seizure or epilepsy type (or both). To determine if a patient does (or does not) have epilepsy, their healthcare provider compares their test results to the guidelines and criteria established by the International League Against Epilepsy (ILAE).

Patients are prescribed treatment based on the type or types of seizures that they are experiencing. There are a variety of treatments available, including medication, dietary changes, devices, and surgery. While the goal of epilepsy treatments is straightforward – no seizures, no side effects – finding the right treatment plan may require trial and error.

Usually, newly diagnosed people with epilepsy will start an oral medication that is appropriate for their diagnosis. If the first drug treatment does not stop their seizures, their neurologist will work with the patient to try other medications, or a combination thereof, as well as evaluate if they are a potential candidate for surgery.

While there are many medications, medical devices, and surgical options to treat epilepsy, right now there are no known cures for epilepsy. However, incredible advancements in research have helped us understand the mechanisms that cause seizures better than at any other point in history. That’s why we must invest in research – to understand the underlying causes of the epilepsies, so we can cure them.

References:

1. Epilepsy Available at: https://www.who.int/en/news-room/fact-sheets/detail/epilepsy.
2. Sirven JI. Epilepsy: A Spectrum Disorder Cold Spring Harb Perspect Med. 2015 Sep 1;5:a022848.
3. Simon D. Shorvon FA, Renzo Guerrini. The Causes of Epilepsy: Common and Uncommon Causes in Adults and Children: Cambridge University Press; 2011.
4. England MJ LC, Schultz AM, et al., editors. Epilepsy Across the Spectrum: Promoting Health and Understanding. Washington DC: National Academies Press (US); 2012.
5. Hirtz D, Thurman DJ, Gwinn-Hardy K, Mohamed M, Chaudhuri AR, Zalutsky R. How common are the “common” neurologic disorders? Neurology. 2007 Jan 30;68:326-337.
6. Aaberg KM, Gunnes N, Bakken IJ, Lund Søraas C, Berntsen A, Magnus P, et al. Incidence and Prevalence of Childhood Epilepsy: A Nationwide Cohort Study Pediatrics. 2017 May;139.
7. QuickStats: Age-Adjusted Percentages of Adults Aged ?18 Years Who Have Epilepsy, by Epilepsy Status and Race/Ethnicity — National Health Interview Survey, United States, 2010 and 2013 Combined. Available at: https://www.cdc.gov/mmwr/volumes/65/wr/mm6523a8.htm#:~:text=The%20prevalence%20of%20epilepsy%20and,and%200.6%25%2C%20respectively.
8. Kroner BL, Fahimi M, Kenyon A, Thurman DJ, Gaillard WD. Racial and socioeconomic disparities in epilepsy in the District of Columbia Epilepsy research. 2013;103:279-287.
9. Friedman D, Fahlstrom R, Investigators E. Racial and ethnic differences in epilepsy classification among probands in the Epilepsy Phenome/Genome Project (EPGP) Epilepsy research. 2013;107:306-310.
10. Epilepsy Foundation. 2014. Epilepsy and Asian Americans. [online] Available at: <https://www.epilepsy.com/living-epilepsy/epilepsy-and/asian-americans> [Accessed 15 December 2021].