Connection Between Down Syndrome and Epilepsy

Epilepsy Commonly Accompanies Down Syndrome

USA, New Jersey, Man with down syndrome talking with care taker. Credit: Tetra Images / Getty Images

There are many causes of epilepsy, and a connection has been shown between children with Down syndrome and epilepsy. Down syndrome, also known as trisomy 21, is a genetic abnormality that is characterized by the presence of an additional chromosome 21. Children with this disorder are faced with multiple organ abnormalities, including characteristic facial features, heart abnormalities, gastrointestinal problems and an increased risk of leukemia.

The majority of individuals older than the age of 50 with Down syndrome may also have symptoms consistent with Alzheimer’s disease or a decline in mental function.

Individuals with Down syndrome also have a higher rate of developing seizures in comparison to the general population. Although the reason for this has not been fully clarified, it is suspected that individuals with Down syndrome are susceptible to seizures due to abnormalities in the structure or function of the brain.

Epilepsy is a common feature of Down syndrome, and the prevalence of epilepsy advances with age. The onset of seizures can occur at two stages of life: either at a very young age or in the third decade of life. At a younger age, individuals with Down syndrome are susceptible of developing infantile spasms (IS) and tonic-clonic seizure with myoclonus. Individuals in the third decade of life are more prone to developing simple partial or complex partial seizures in addition to tonic-clonic seizures.

It is estimated that 46% of Down's patients older than the age of 50 have a diagnosis of epilepsy. Additionally, some cases of seizure onset occuring later in life (after the age of 50 years) have also been reported, although this is not seen as frequently.

If you are concerned about having a child with Down syndrome, discuss your concerns and family planning with your healthcare provider.

If you have a child with Down syndrome, this does not necessarily mean that your child will develop epilepsy. It is important, however, to understand the somewhat close relationship that these two conditions share. Be sure to take your child to their regular checkups and discuss any concerns you may have with your child’s pediatrician.

What Is Down Syndrome?

Down syndrome occurs when a person has an extra copy of chromosome 21. Normally, a person has 46 chromosomes, or 23 pairs of chromosomes. People with Down syndrome have 47 chromosomes. Of note, chromosomes are blocks of genetic information necessary for life and development.

An extra copy of a chromosome is referred to as "trisomy," and Down syndrome is also referred to as trisomy 21. Many other abnormalities in chromosome numbers are incompatible with life and result in first-trimester miscarriage.

What Are Some Physical Characteristics of Down Syndrome?

Although in many cases Down syndrome can be readily recognized based on physical characteristics, not all people with Down syndrome are the same and different people have different abilities and disabilities.

Here are some physical characteristics of people with Down syndrome:

  • small ears
  • eyes with an upward slant
  • shortened neck
  • flattened face
  • shortened stature
  • small hands and feet
  • crease in the palm of the hand


Menendez M. Down syndrome, Alzheimer’s disease and seizures. Brain & Development 27 (2005) 246–252.

Moeller JC, Hamer HM, Oertel WH et al. Late-onset myoclonic epilepsy in Down’s syndrome (LOMEDS). Seizure. 2001 Jun;10(4):303-6.

Goldberg-Stern H, Strawburg RH, Patterson B, et al. Seizure frequency and characteristics in children with Down syndrome. Brain & Development 23 (2001) 375–378.

Stafstrom CE, Patxot DF, Gilmore HE, Wisniewski KE. Seizures in children with Down syndrome: etiology, characteristics and outcome. Dev Med Child Neurol 1991;33:191–200.

Romano C, Tine A, Fazior G, Rizzo R, Colognola RM, Sorge G, et al. Seizures in patients with trisomy 21. Am J Med Genet Suppl 1990;7:298–300.

Stafstrom CE. Epilepsy in Down syndrome: clinical aspects and possible mechanisms. Am J Ment Retard 1993;98:12–26.

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