The following information is intended solely for educational purposes. It should not be construed as medical advice nor a substitute for medical care. Autism Speaks does not engage in the practice of healthcare or the provision of healthcare advice. Please consult your or your child’s physician for guidance about care and treatment.
Also see this website's Family Services Resources on Autism and Epilepsy.
Epilepsy is a brain disorder marked by recurring seizures, or convulsions. Epilepsy is more common among individuals with autism than among the general population. Seizures are more common in individuals with lower verbal abilities.
Studies suggest that 15 to 30 percent of individuals with autism also have epilepsy.
About 5 percent of those who develop epilepsy in early childhood also develop autism.
Diagnosing and treating epilepsy is critically important. Research shows that individuals with autism and untreated epilepsy are at greater risk for overall poor health, and in extreme circumstances, premature death. Compared to those without seizures, children with ASD and seizures are also more likely to have sleep difficulties and behavior problems.
Experts propose that some of the brain abnormalities associated with autism may also contribute to seizures. These abnormalities may include chemical imbalances in the molecules that send signals between brain nerve cells. According to the National Institute of Neurological Disorders and Stroke (NINDS), some individuals with epilepsy have abnormally high levels of neurotransmitters that increase neuron activity (excitatory). Others have low levels of neurotransmitters that decrease neuron activity (inhibitory). An overload of neuron activity can result in seizures.
The good news is that epilepsy can usually be controlled with medication.
Recognizing Epilepsy Symptoms
Seizures can begin at any age. Characteristic symptoms include:
- Unexplained staring spells
- Stiffening of muscles
- Involuntary jerking of limbs
- Facial twitching
- Unexplained confusion
- Severe headaches
Other less-specific symptoms can include:
- Sleepiness or sleep disturbances
- Marked and unexplained irritability or aggressiveness
- Regression in normal development
Like autism, epilepsy exists on a spectrum. Severity varies widely among people with epilepsy. There are several types of seizures, each with somewhat different symptoms:
- Tonic-clonic seizures are the most common. Also known as gran mal seizures, they produce muscle stiffening followed by jerking. Gran mal seizures also produce loss of consciousness.
- Absence seizures can be difficult to recognize. Also known as petit mal seizures, they are marked by periods of unresponsiveness. The person may stare into space. He or she may or may not exhibit jerking or twitching.
- Tonic seizures involve muscle stiffening alone.
- Clonic seizures involve repeated jerking movements on both sides of the body.
- Myoclonic seizures involve jerking or twitching of the upper body, arms or legs.
- Atonic seizures involve sudden limpness, or loss of muscle tone. The person may fall or drop his or her head involuntarily.
Diagnosing and Treating Epilepsy in Individuals with Autism
If a parent or guardian suspects that a child or adult is having seizures, it’s important to seek evaluation by a neurologist.
Most likely, the neurologist will order an electroencephalogram (EEG). An EEG is a noninvasive process that involves the placing of electrodes on an individual’s head in order to monitor activity in the brain. By analyzing the brain activity patterns that the EEG measures, the neurologist can determine if someone is having seizures.
Treating epilepsy in individuals with autism follows the same principles as treatment of epilepsy in any person. Typically, the physician selects an anti-epileptic drug based on several considerations such as the type and severity of seizures and their associated EEG patterns.
Anti-epileptic drugs do not cure epilepsy. In most cases, however, they can prevent or minimize seizures. At present, U.S. doctors can choose from more than twenty medications. After starting a medication, it’s important to closely monitor effectiveness and possible side effects. Relatively common side effects include mild fatigue, abdominal discomfort or dizziness. These tend to ease off after the first weeks of use. To minimize side effects, the doctor may start medications at a low dose and slowly increase it. Dosage adjustments are to be expected when taking anti-epileptic medications.
Epilepsy drugs eliminate seizures in around two-thirds of patients. More difficult-to-control cases sometimes respond to combinations of two or more medications.
When medications fail to control seizures, physicians and families can discuss other options. These include vagus nerve stimulation, a technique that prevents seizures by sending pulses of electrical energy to the brain through a device that acts like a “pacemaker” for the brain. Another option is the surgical removal of seizure-producing areas of the brain.
Autism Speaks Autism Treatment Network is dedicated to enhancing the ability of pediatricians and other doctors to treat associated medical conditions including epilepsy. Many ATN centers are staffed by neurologists with expertise in treating children with autism and epilepsy.
Sudden Unexpected Death in Epilepsy
The combination of autism and epilepsy is often associated with overall poor health and, in extreme circumstances, premature death. According to a recent scientific literature review, the incidence of Sudden Unexpected Death in Epilepsy (SUDEP) ranges from 1 to 93 cases per 10,000 people with epilepsy per year (depending on the study).
Unexpected death is more common in those with uncontrolled grand mal seizures, including those who are who are not taking sufficient antiepileptic medication to control their seizures. Causes of death include not breathing, loss of normal heart rhythm, brain dysfunction or a combination of these.
Physicians work with patients on strategies that minimize the risk of death associated with epilepsy. First and foremost is prevention of seizures to the utmost extent possible. This includes finding the right medicines and ensuring that the affected child or adult takes the proper dosage at the proper time. Also useful are seizure monitors that can notify caretakers when a seizure is beginning.
Research on Epilepsy and Autism
Recent research suggests that certain gene mutations, or changes in DNA, may increase the occurrence of both epilepsy and autism. The best understood of these genes cause rare syndromes associated with autism and epilepsy. These syndromes include tuberous sclerosis, a genetic disorder that causes tumors to form in organs. Forty percent of people with tuberous sclerosis also develop autism, and ninety percent experience seizures. Cortical dysplasia-focal epilepsy, a congenital disorder caused by abnormal development of neurons, is another such syndrome. Nearly two-thirds of those affected also have autism.
More research is needed to increase understanding of the shared brain networks, genes and other biological mechanisms that cause both autism and epilepsy. Autism Speaks is currently partnering with the International League Against Epilepsy and Citizens United for Research in Epilepsy to further this research. You can explore epilepsy studies funded by Autism Speaks here.
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