What is Status Epilepticus and SUDEP?

What is Status Epilepticus

Status epilepticus is a potentially life-threatening condition in which a person either has an abnormally prolonged seizure or does not fully regain consciousness between seizures. Most people agree that any seizure lasting longer than 5 minutes or if a second seizure occurs before recovery, should, for practical purposes, be treated as though it was status epilepticus. Status epilepticus affects about 195,000 people each year in the United States and results in about 50,000 deaths.

It is important to treat a person with status epilepticus as soon as possible. Doctors in a hospital setting can treat status epilepticus with several different drugs and can undertake emergency life-saving measures, such as administering oxygen, if necessary. People in status epilepticus do not always have severe convulsive seizures. Instead, they may have repeated or prolonged non convulsive seizures. This type of status epilepticus may appear as a sustained episode of confusion or agitation in someone who does not ordinarily have that kind of mental impairment.

What is SUDEP

Sudden Unexpected Death in Epilepsy is a mysterious, rare condition, better known as SUDEP, in which typically young or middle-aged people with epilepsy die without a clearly defined cause. By definition, (1) death is sudden and unexpected, (2) a clear cause of death must be absent, and (3) victims must have had epilepsy. Victims are often found in bed with or without signs of having had a convulsive seizure, but were otherwise in a reasonable state of health at the time of death. Although seizures are suspected to have occurred prior to death, there should be no evidence of seizure as the direct cause of death.

What causes SUDEP

Although the cause of death is unknown, some researchers suggest that a seizure causes an irregularity in the heart rhythm. More recent studies have suggested that a combination of impaired breathing (apnea), increased fluid in the lungs (impairing the exchange of oxygen and carbon dioxide), and being face down on the bed all combine to cause death due to impaired respiration. In many cases, death probably occurs after a seizure has ended.

How common is SUDEP

Various report information gathered shows the number of people with epilepsy who die of sudden unexpected death in epilepsy (SUDEP) to be rare. The incidence of SUDEP in the general epilepsy population has been reported to be 0.09–1.2/1,000 person-years. This incidence is higher, 1.1–5.9/1,000 person-years, in patients with medically refractory epilepsy and even higher, 6.3–9.3/1,000 person-years, in patients who have failed respective epilepsy surgery ({A} Tomson T, Nashef L, Ryvlin P, Sudden unexpected death in epilepsy: current knowledge and future directions, Lancet Neurol, 2008; (11):1021–31. {B} Devinsky O, Sudden, unexpected death in epilepsy, N Engl J Med, 2011;365(19):1801–11.)

One most recent study out from the Institute of Medicine 2012, entitled; Epilepsy Across the Spectrum: Promoting Health and Understanding sites “SUDEP numbers vary from 1 in 10,000 newly diagnosed people with epilepsy to 9 of every 1,000 candidates for epilepsy surgery.” It is clear that much more research and data collection is needed in order to get more accurate numbers.

Although the risk is highest in people with severe, intractable epilepsy that have frequent seizures and take large doses of many anti-epileptic drugs. A recent 40 year follow-up of children once diagnosed with epilepsy suggests that SUDEP may account for approximately 30% of all deaths in people with epilepsy (Sillanpää & Shinnar 2010). However, with poor case identification and inconsistencies in the investigation and recording of the deaths, these numbers could very well be an underestimate.

The lowest risk is seen among people with newly diagnosed Epilepsy. The risk is highest in young male adults (ages 20-40), with frequent convulsive seizures, taking several anti-epileptic medications. Combination therapy (poly-therapy) with anti-epileptic drugs had a 3 times higher risk compared with those on a single anti epileptic drug (mono therapy) in a recent combined ILAE analysis. There is no conclusive evidence of greater risks associated with the use of individual specific anti-epileptic drugs. On the other hand, SUDEP is rare in patients with new onset epilepsy, in patients without convulsive seizures as a seizure type, and in patients with well controlled seizures.

What are the risk factors for SUDEP
Major risk factors for SUDEP appear to relate to the severity of the epilepsy, as SUDEP is more common in people with:

  • Seizures that can’t be controlled
  • Treatment with multiple anti-convulsant drugs
  • Having long standing chronic epilepsy
  • Generalized tonic-clonic seizures
  • Seizures that happen at night (called nocturnal seizures)
  • Not taking anti convulsant medicine as prescribed
  • Stopping the use of anti convulsant medicine abruptly
  • Developmental delays
  • Onset of epilepsy at a young age

A few safety precautions can minimize the chances of SUDEP

  • Patients should make sure to take the medications prescribed for them.
  • Patients should visit with their doctor regularly, especially if convulsive seizures are not completely controlled.
  • Adult patients with a high likelihood of tonic-clonic seizures in sleep should be supervised whenever possible. (SUDEP is extremely rare in children with epilepsy and in other patients who are well monitored. In fact, supervision has emerged as a protective factor for SUDEP, independent of seizure control.)
  • Basic first aid should be provided during a seizure, including rolling the person onto one side, checking respiration and avoiding putting any object in the patient’s mouth.
  • Family members and/or caregivers of patients with uncontrolled convulsive seizures should learn cardiopulmonary resuscitation.

IOM Summary: Data seem to suggest that the mechanism of SUDEP may be dependent upon individual susceptibility to one or a combination of factors. These may include: seizure-related central apnea and/or lung edema with respiratory death; seizure-related hypoxia plus acute pulmonary changes and systemic acidosis leading to a fatal arrhythmia; an inherited cardiac ion channelopathy combined with acute seizure-related cardiac autonomic disruption leading to a fatal arrhythmia. Added to the mix is the unknown of acute psychological stress. The mechanism(s) of SUDEP remain a mystery, but with a growing interest in investigating the mechanistic variables, there is reason to be optimistic that eventually it will be solved.

I’m work to raise SUDEP awareness in part by teaching seizure recognition and first aid. The ultimate goal of all SUDEP research is to prevent deaths caused by seizures. This requires a better understanding of it, by comparing people who die from SUDEP to people living with epilepsy, and people with epilepsy who die of other causes.

 

About Epilepsy

What IS epilepsy?

Seizures are a symptom of epilepsy. Epilepsy is the underlying tendency of the brain to release electrical energy that disrupts other brain functions. So the seizure is the symptom of this underlying condition. Having a single seizure does not necessarily mean a person has epilepsy. Epileptic seizures are usually convulsive, but not always. Seizures can last from a few seconds up to minutes or hours, depending on the intensity of neuronal excitability. Epilepsy treatment usually requires the regular intake of controlled anti-convulsive medications.

Epilepsy will affect every person (directly or indirectly) at some point during their lifetime. There are approximately 30,000 (about 1% of the population) people in Orange County, California affected by epilepsy and 380,000 people with epilepsy and seizure disorders throughout the state of California. Most people with epilepsy lead outwardly normal lives. Approximately 80 percent can be significantly helped by modern therapies, and some may go months or years between seizures. However, the disease can and does affect daily life for people with epilepsy, their family, and their friends. Approximately 1 in 10 people will experience a seizure at some point in their life; about 1 in 20 children have epilepsy; and nearly 1 in 26 people will develop epilepsy during their lifetime.

Epilepsy affects about 65 million people worldwide. An underestimated 3.4 million Americans are diagnosed with epilepsy, with approximately 150,000 new cases diagnosed in the United States each year. The onset of epilepsy is highest in children and older adults; depending on the diagnostic criteria and study method used. There are about 326,000 children in America with epilepsy under the age of 15. Epilepsy affects 1 in 20 children. It may be associated with another serious and difficult to treat syndrome, developmental disorder or genetically related condition. The social impact on children with epilepsy can be severe and they have almost a 45% higher risk of being bullied.

As many as 50,000 Americans die each year from seizures and related causes, including drowning and other accidents. It’s widely misunderstood condition that too often goes untreated and misdiagnosed. By some estimates, the mortality rate for people with epilepsy is two to three times higher—and the risk of sudden death SUDEP is 24 times greater than that of the general population.

Epilepsy ranks 7th on the global burden of mental health, neurological and substance use disorders worldwide after Alzheimer’s, schizophrenia, and depression and alcohol use; but ahead of migraine, panic disorder, insomnia, post-traumatic stress, Parkinson’s disease, and multiple sclerosis. Law enforcement personnel are becoming educated about the different intensities and types of epileptic seizures in order to prevent misinterpreting behavior, such as the appearance of intoxication, exhibited by persons experiencing a seizure or in or in the immediate recovery period.

What causes epilepsy?

In approximately 70% of people diagnosed with epilepsy, the cause is not known. The remaining 30% of patients are found to have common causes such as stroke heredity, lead poisoning, infection, brain tumor/head trauma, prenatal brain development problems and more. About 1% of the general population will develop epilepsy. Although the risk is higher in people with certain medical conditions such as Alzheimer’s disease, Autism, Cerebral palsy, Mental retardation and Stroke.

In some cases, head injury can lead to seizures or epilepsy. Simple safety measures can protect people from seizures, epilepsy and other problems that result from head injury.  Other types of epilepsy may be induced through occupational damage, due to repeated exposure to acoustic or visual stimuli, or as a result of an isolated high-intensity auditory or visual stimulus.

Whatever the case, the sensory stimulation induces chemical changes in the related brain areas, causing a kind of electrical short-circuit, with a group of neurons briefly firing in a synchronous rhythm. These stimuli-induced forms of seizures are known as acquired epilepsy. When the epilepsy results from an identified cerebral condition, it is classified as symptomatic. Non-symptomatic epilepsies are those occurring in people who do not present brain abnormalities or neurological disorders other than the seizures.

Epilepsy is associated with a variety of developmental and metabolic disorders. Epilepsy is just one of a set of symptoms commonly found in people with these disorders. Sometimes, epilepsy develops as a result of brain damage (simple safety measures can protect people from seizures that result from head injury) and from other disorders. For example, brain tumors, alcoholism, and Alzheimer’s disease frequently lead to epilepsy because they alter the normal workings of the brain. Strokes, heart attacks, and other conditions that deprive the brain of oxygen also can cause epilepsy in some cases. Meningitis, AIDS, viral encephalitis, and other infectious diseases can lead to epilepsy, as can hydrocephalus — a condition in which excess fluid builds up in the brain. Epilepsy also can result from intolerance to wheat gluten (also known as celiac disease), or from a parasitic infection of the brain called neurocysticercosis. Seizures may stop once these disorders are treated successfully.

Seizures can result from exposure to lead, carbon monoxide, and many other poisons. They also can result from exposure to street drugs and from overdoses of antidepressants and other medications. These seizure triggers do not cause epilepsy but can provoke first seizures or cause breakthrough seizures in people who otherwise experience good seizure control with their medication. Sleep deprivation in particular is a universal and powerful trigger of seizures. For this reason, people with epilepsy should make sure to get enough sleep and should try to stay on a regular sleep schedule as much as possible.

For some people, light flashing at a certain speed or the flicker of a computer monitor can trigger a seizure; this problem is called photosensitive epilepsy. Smoking cigarettes also can trigger seizures. The nicotine in cigarettes acts on receptors for the excitatory neurotransmitter acetylcholine in the brain, which increases neuronal firing. Seizures are not triggered by sexual activity except in very rare instances.

What are the benefits of keeping a seizure diary? Keeping a daily seizure diary (a good one is http://www.seizuretracker.com) is one way to make living with epilepsy easier. By tracking your seizure activity and epilepsy medication routine, you can help provide valuable diagnosis information to your neurologist/epileptologist.