Many children and youth with autism spectrum disorders are also diagnosed with epilepsy, also called a seizure disorder. A seizure is a disturbance in the electrical activity of the brain. Twenty-five million Americans (1 in 10) have had, or will have, at least one seizure at some time in their lives. Among children and adolescents with autism, from 20-40% experience some form of epilepsy between early childhood and adulthood, which can be very alarming to parents.
In early childhood, many young children have one or several seizures during periods of high fever, such as a bout of the flu. They may never have another seizure the rest of their life. But for other children with autism, those initial febrile seizures may be followed by other epileptic episodes without fever, repeatedly over time. For some, epileptic seizures will be a part of their life indefinitely.
Epileptic seizures may include muscle spasms, mental confusion, loss of consciousness and/or uncontrolled or aimless body movements. Some individuals cannot remember what happened immediately before or during a seizure. There is an old myth that a person having an epileptic seizure may swallow his or her tongue. Medical experts say that is impossible, though some individuals bite their tongue during a seizure.
There are two main types of seizures:
Generalized involving an electrical discharge of nerve cells throughout much of the brain. They include:
Tonic-Clonic seizures or "grand mal" (loss of consciousness, stiffening of body, jerking of limbs) and Absence seizures or "petit mal" (blank spells, staring, slight twitching)
Partial Epileptic Seizures- begin with a discharge of neurons in just one part of the brain. They include Simple Partial seizures (uncontrolled body movements often with one hand or part of the body, brief changes in sensory perceptions) and Complex Partial seizures (confusion, loss of awareness, aimless movements). Occasionally people exhibit violent outbursts of aggression or property destruction during a Complex Partial Seizure. In the past this type of epilepsy was called Psychomotor Epilepsy. Infantile Spasms (babies have sudden, jerking seizures) are considered a type of Partial Epilepsy
Seizures may be frequent or rare. Some children have many seizures per day, and others may only have a few seizures per year. Seizure may last a few seconds or several minutes. They may be severe or mild. A person can have more than one type of seizure, and the pattern of seizures may change with time, which can be very confusing to parents. Children with autism and higher IQ are less prone to seizures than those with lower IQ.
Anti-Epileptic Medications (AEDs)
Antiepileptic medications can control seizures in about 70% of patients. However, medications won't cure epilepsy. An accurate diagnosis of the type of epilepsy is important in choosing the best treatment. Narrow Spectrum Antiepeliptic Medications mostly work for specific types of seizures (such as partial, focal, or absence, myoclonic seizures). Broad Spectrum AEDs additionally have some e
ffectiveness for a wide variety of seizures (partial plus absence myoclonic seizures). Examples of Narrow-Spectrum AEDs are Dilantin, Tegretol and Neurontin. Examples o Broad Spectrum AEDs are Depakote, Topamax and Klonopin.
Anyone who exhibits persistent seizure activity or who does not regain consciousness for five minutes or more after a witnessed seizure should be considered to have status epilepticus. For most children at highest risk, maintaining abortive therapy in the home may be a reasonable precaution. Rectal, nasal spray, or within the cheek pouch and sublingual ways of administering medication may be used. Versed (midazolam) can be given by nasal spray or inserted in the child’s cheek pouch. Rectal administration of Valium (diazepam) or Ativan (lorazepam) is generally safe when under close supervision of the child’s neurologist. When status epilepticus persists over an extended period on a given occasion, the child should be transported to an emergency room by emergency personnel to provide oxygen and intubation if necessary. There is some evidence of small but significant decline in intellectual functioning over a five year period for individuals with persistent Status Epilepsy.
The ketogenic diet is a high-fat, adequate-protein, low carbothydrate diet that in medicine is used primarily to treat difficult-to-control (refractory) epilepsy in children. Some neurologists say that when 2-3 or more antiepileptic drugs have been tried and failed to reduce seizures, the ketogenic diet should be considered. The diet mimics aspects of starvation by forcing the body to burn fats rather than carbohydrates. Success rates with the ketogenic diet have been modest, in the range of 30% showing reductions of 50% in seizure frequency. Common but easily treatable short-term side effects include constipation and low blood sugar, if there is an initial fast. Cholesterol may increase by around 30% which could pose problems with long term treatment. Long-term use of the ketogenic diet in children increases the risk of retarded growth, bone fractures, and kidney stones. Supplements are necessary to counter the dietary deficiency of many micronutrients.
Vagal stimulation is only used in individuals whose numerous seizures are unresponsive to medications and the ketogenic diet has been ineffective. An electrical lead is surgically attached to the left vagus nerve that runs along side the espophagus and windpipe, and delivers a very small electrical current that continuously cycles between on and off periods. The programmable
pacemaker is placed on the patient's upper chest. In one study, 55.08 % of treated children and youth had a satisfactory outcome (either no or minimal seizures or sizable improvement), and 44.92 %, there was no worthwhile improvement of seizures. Other studies have reported similar results. In general, vagus nerve stimulation is the last choice of epileptologists before surgical removal of the brain tissue causing the seizures in treatment-resistant cases..
The goal of epilepsy surgery is to identify an abnormal area of the brain’s surface from which the seizures originate and remove it without causing any significant functional impairment. The primary components of the pre-surgical evaluation includes a detailed clinical history and physical examination, advanced brain imaging, video-EEG monitoring, neuropsychological testing and assessment of psychological and social functioning. If the information obtained during the noninvasive pre-surgical evaluation consistently points towards a single area of the brain as being the site of seizure onset, then surgery may be appropriate to remove that area. If the brain scan demonstrates a well-characterized lesion and is consistent with the clinical features of the seizures, then surgery may be reasonable. The most common type of surgery removes layers of scarred nerve cells within the hippocampus, two structures shaped like thin loaves of French bread running along both the sides of the brain adjacent to the underside. This surgical procedure (meticulous removal of mesial temporal sclerotic tissue) has a high success rate, often with minimal side effects. Neurosurgery always involves some risk of damage to other adjacent structures, though that is usually minimal. Surgery is nearly always the last resort after the above approaches have been tried and failed to provide relief from frequent debilitating seizures.
Resources: The books by Blackburn (2003) and Freeman, Vinning and Pillas (2002) are excellent starting points for parents of children with epilepsy and autism. Timely information about epilepsy diagnosis and treatment can be found at The National Institute of Neurological Disorders and Stroke web site; NINDS Epilepsy Information Page.
Blackburn, LB (2003) Growing up with epilepsy: A practical guide for parents. Demos Health Publisher
Dodrill and Wilensky. Intellectual impairment as an outcome of status epilepticus. Neurology 1990;40[Suppl 2]:23-27. From Devinsky O and Tarulli A. Progressive cognitive and behavioral changes in epilepsy. In: Devinsky O and Westbrook LE, eds. Epilepsy and Developmental Disabilities. Boston: Butterworth-Heinemann; 2001;133-149. With permission from Elsevier
Fisher, R.S. Epilepsy.ComNewsletter. Summary of Antiepilpetic Drugs http://www.epilepsy.com/epilepsy/newsletter/sept09/aeds
Freeman,JM, Vinning, EPG and Pillas,DJ (2002) Seizure and epilepsy in childhood: A guide, 3rd edition. Baltimore, MD: The Johns Hopkins University Press.
Gabis, L, Pomeroy, J, Andriola, MR (2005) Autism and epilepsy: Cause, consequence, comorbidity, or coincidence? Epilepsy and Behavior 7: 652-56
Gillberg, C. (1991) The Treatment of Epilepsy in Autism. J. Autism Develop.Disord. 21: 61-77
Kabir,SM et.al. (2009) Vagus nerve stimulation in children with intractable epilepsy: indications, complications and outcome. Childs Nerv System. 25: 1097-100.
Malow, BA (2006) Searching for Autism Symptomatology in Children with Epilepsy—A New Approach to an Established Comorbidity. Epilepsy Curr. 6(5): 150–152.
The National Institute of Neurological Disorders and Stroke web site; NINDS Epilepsy Information Page http://www.ninds.nih.gov/disorders/epilepsy/epilepsy.htm
Stafstrom CE (2006)Dietary Approaches to Epilepsy Treatment: Old and New Options on the Menu. EpilepsyUSA, reproduced in Epilepsy Foundation Newsroom. http://www.epilepsyfoundation.org/epilepsyusa/diet200607.cfm
WebMD Medications to treat Seizures http://www.webmd.com/epilepsy/medications-treat-seizures
Yasuhara, A. (2010) Correlation between EEG abnormalities and symptoms of autism spectrum disorder (ASD). Brain Dev. 32:791-8.