What is Sudden Unexpected Death in Epilepsy?
Epilepsy is a common neurological condition that affects up to 1 in 26 people. It’s defined by recurrent seizures that occur without any apparent cause. People with epilepsy have a higher risk of death, including from causes not related to epilepsy, such as suicide, cancer, and heart disease, as well as causes related to epilepsy. These can include severe seizures (known as status epilepticus), side effects of anti-seizure medications, accidents involving motor vehicles or bicycles, withdrawal from alcohol, pneumonia likely caused by inhaling food or drink, and drowning.
A key concern is Sudden Unexpected Death in Epilepsy (SUDEP), which is defined as a death in someone with epilepsy that’s not caused by an accident (like drowning or severe seizures) or other known causes, but is often associated with a seizure. SUDEP is a leading cause of death for people with epilepsy. Research shows that 55% of 60 deaths in a study of people who developed epilepsy as children were related to epilepsy, with 30% being sudden, unexplained deaths. The risk of such a sudden, unexplained death was 7% at 40 years of age. As SUDEP often goes unwitnessed, diagnosis is typically only possible after death.
Efforts to distinguish SUDEP from other causes of death in epilepsy have led to distinguishing it into four categories: definite, probable, possible, and unlikely SUDEP. These categories help in studying the risks, causes, and prevention strategies associated with SUDEP more accurately. This increases awareness of SUDEP among health professionals and the general public, leading to better patient advice and potential changes to risk factors.
What Causes Sudden Unexpected Death in Epilepsy?
Sudden, unexpected death in epilepsy, or SUDEP, has been researched extensively. Information from past patient records, hospitals, a significant study called the MORTEMUS trial, and eyewitness accounts have identified common symptoms that occur during or just after a seizure. These symptoms include changes to breathing and heart rhythm, as well as a reduction in brain function.
Research has shown that breathing factors often play a role in SUDEP. Many times, people who have died from SUDEP were found in a face-down posture, usually while asleep, which could mean they might have suffocated. The MORTEMUS trial mentioned above reported several cases of SUDEP, along with other cases of cardiac arrests and near-SUDEP instances. The study concluded that anyone in a hospital epilepsy unit should be carefully watched at night, as changes to heart rhythm and difficulty in breathing can happen after a seizure, which could potentially lead to SUDEP.
While changes in heart rhythm have been identified in cases of SUDEP, issues with breathing (like not breathing, irregular breathing patterns, or lack of oxygen) are more commonly connected to a decrease in brain function. These symptoms are typically observed in instances of SUDEP that were witnessed. Since the heart’s rhythm functions independently of the brain, if changes in the heart rhythm were observed in SUDEP cases, it may indicate another mechanism of the condition, like channelopathy, a disease that affects the proteins in our cells responsible for electrical signaling. In instances where brain wave activity was recorded using video electroencephalography (or EEG), significant changes in heart rhythm were not observed.
Some think that a reduction in overall brain activity might be the main event that leads to SUDEP. When the whole brain’s function decreases, it can suppress the areas responsible for controlling breathing, which can lead to severe acidosis, a buildup of too much acid in the body. This decrease in brain function can then cause your carbon dioxide levels to rise, resulting in a condition called hypercapnia acidosis, and could potentially trigger a condition known as laryngospasm, where the vocal cords suddenly seize up or close shut.
Risk Factors and Frequency for Sudden Unexpected Death in Epilepsy
Sudden, unexpected death from epilepsy, also known as SUDEP, can occur in anyone, from young children to older adults. It is most common in people aged 20 to 45. It seems to be more likely in certain groups of people with epilepsy. For instance, those seen in an epilepsy center, those with uncontrolled epilepsy, those living in residential care facilities, or patients who are referred for epilepsy surgery. Males, and those who had epilepsy start in childhood, are also more likely to experience SUDEP.
Large research studies in the USA and Europe have found higher SUDEP rates in people facing obstacles to getting good healthcare. These obstacles include being unemployed, lack of access to medications and treatments, and living far from healthcare providers. SUDEP can occur in different types of epilepsy, but doesn’t seem to affect people with only absence (brief periods of ‘blanking out’) or myoclonic (sudden, brief jerks of a muscle or group of muscles) seizures.
A study in Sweden found that patients who have a certain type of seizure, generalized tonic clinic seizures (GTCS), had a ten times higher risk of SUDEP, and most of these patients lived alone. A two times higher risk of SUDEP was found in individuals who had been diagnosed with substance abuse or alcohol dependence.
- SUDEP is most common in people aged 20 to 45.
- It is more likely in people who:
- Are seen in an epilepsy center
- Have uncontrolled epilepsy
- Live in residential care facilities
- Are referred for epilepsy surgery
- Are males
- Had epilepsy start in childhood
- Higher SUDEP rates are seen in people who:
- Are unemployed
- Lack access to medications and treatments
- Live far from healthcare providers
- Patients with GTCS have a ten times higher risk of SUDEP, and most live alone.
- Individuals who had been diagnosed with substance abuse or alcohol dependence have a two times higher risk of SUDEP.
Signs and Symptoms of Sudden Unexpected Death in Epilepsy
Sudden unexpected death in epilepsy (SUDEP) is associated with different risk factors. For instance, having multiple generalized tonic-clonic seizures in a year significantly raises the risk of SUDEP. Similarly, those who don’t add anti-seizure drugs when their epilepsy is uncontrolled are at a higher risk of SUDEP. Other significant risk factors of SUDEP in children include early-onset epilepsy and developmental delays.
On the other hand, there are a few factors that can actually decrease the risk of SUDEP. They include the presence of another person in the same room who can potentially intervene during a seizure, and the use of a monitoring or listening device in the room of the person at risk. However, it’s crucial to note that the majority of SUDEP cases are unwitnessed. Studies on SUDEP cases in epilepsy monitoring units contribute to collecting more patient data, allowing for better identification of risk factors.
The American Academy of Neurology conducted an extensive study on over 20 other potential risk factors, such as gender, age at the start of seizures, type and dose of epilepsy drugs used, type of epilepsy, other medical and psychological disorders, brain scan results, and EEG patterns. However, none of these factors were strongly linked to a higher or lower risk of SUDEP.
Other potential risk factors being currently researched include the time of day the seizure occurs, physiological changes at different times, and body position during the seizure. Additionally, non-modifiable risk factors, like severe epilepsy, early onset of epilepsy, and genetic factors related to potassium and sodium channels are also being studied. Specific genetic variants, such as KCNH2 and SCNC5, are crucial to identify as they can influence medical treatment decisions.
Testing for Sudden Unexpected Death in Epilepsy
Sudden unexpected death in epilepsy, often referred to as “SUDEP,” is an event where a person with epilepsy dies suddenly and unexpectedly, and we can’t find any apparent alternative cause of death. This means, when we suspect SUDEP, it’s essential to rule out any other possible causes of death to be sure that’s what happened. The process of diagnosing SUDEP is often based on the medical history and autopsy findings.
Figuring out the cause of death is a complex process due to many factors that might be involved in someone’s death. Being accurate with this step is crucial because it can impact legal aspects and public health policies.
To make the process more orderly, a classification system was suggested that takes into account various aspects and existing health conditions of the deceased. This 8-tiered system breaks down as follows:
- Definite SUDEP: This is when a patient with epilepsy dies suddenly and unexpectedly. There doesn’t necessarily have to be evidence of a recent seizure, and the autopsy doesn’t show a cause of death other than epilepsy.
- Definite SUDEP plus comorbidity: This is similar to definite SUDEP, but the patient also had another medical condition that could’ve contributed to the death.
- Probable SUDEP: This is when an autopsy wasn’t performed, but the patient with epilepsy died unexpectedly.
- Probable SUDEP plus comorbidity: Similar to probable SUDEP, but with another medical condition that could’ve contributed to the death.
- Possible SUDEP: This is when there was a sudden death in a patient with epilepsy, but there’s a likely alternative cause of death.
- Resuscitated SUDEP: This is when a patient with epilepsy was resuscitated and survived for more than an hour after a cardiopulmonary arrest where no other cause was found.
- Not SUDEP: A clear alternative cause of death was identified.
- Unclassified: There’s not enough information to make a definitive diagnosis.
Certain findings that can hint towards a SUDEP diagnosis include the patient being found lying face down, indications of recent seizures like oral trauma, bruises, or a hemorrhage in the eye, or cuts on the head or limbs. Though these signs are not exclusive to SUDEP, they can help substantiate the diagnosis of a recent seizure.
Treatment Options for Sudden Unexpected Death in Epilepsy
Sudden, unexpected death in epilepsy (SUDEP) is a serious risk associated with epilepsy and very frightening for patients and their immediate families. SUDEP means an epileptic person dies suddenly with no clear cause, so it’s important to look at ways to lower the risk of it happening. Techniques to reduce the risk of SUDEP can range from improving control of epilepsy episodes, using devices to alert when seizures are happening, adjusting patient position to help breathing during a seizure, and using certain medications to minimize the chance of breathing troubles.
Commonly recommended actions are reducing the factors that might lead to SUDEP. This can include taking steps to lessen the frequency of epilepsy episodes, ensuring medication is taken as prescribed, and considering more advanced treatments like surgery for suitable patients. Lately, devices that monitor seizures (like alarms, heart rate monitors, and bed sensors) are seen as promising, and more evidence is emerging about their effectiveness.
However, a comprehensive review in 2012 found that while these monitoring methods might accurately detect severe, convulsive seizures (also known as generalized tonic-clonic seizures or GTCS), there isn’t enough evidence to suggest they can prevent SUDEP. As well, the usefulness of interventions such as “safety pillows” to minimize the risk of suffocation or using certain drugs to lessen low-breathing issues isn’t strongly backed by data yet.
What else can Sudden Unexpected Death in Epilepsy be?
When someone unexpectedly dies while having epilepsy, there are several other potential causes of death that doctors consider and these can usually be identified through an autopsy. These often include:
- Drowning
- Heart muscle disease (Cardiomyopathy)
- Irregular heart rhythms (Cardiac arrhythmia)
- Overdosing on drugs
- Lung disease (Pulmonary disease)
- Injury or accident (Trauma)
- Bleeding within the brain (Intracranial hemorrhage)
What to expect with Sudden Unexpected Death in Epilepsy
Sudden unexpected death in epilepsy, or SUDEP, is a condition that can sadly result in loss of life. However, when it comes to epilepsy as a whole, patient outcomes can vary greatly – from poor to exceptional.
There are multiple tools available to determine the risk of a patient with epilepsy developing SUDEP. One such tool is the ‘SUDEP-7 inventory’, which analyses a number of factors to assess each patient’s risk, including:
* Having three or more major seizures (known as ‘tonic-clonic seizures’) in the past year.
* Having one or more major seizures in the past year.
* Having one or more seizures of any type in the past year.
* Suffering more than 50 seizures per month in the past year.
* Having epilepsy for 30 years or more.
* Being treated with three or more antiseizure medications.
* Having a measured IQ of less than 70, indicating an intellectual disability.
Should a patient have any of the risk factors listed above, it increases their risk score according to this tool (the highest score possible being 12). However, it’s important to understand that an individual’s risk score has not been proven to predict SUDEP accurately.
Statistically speaking, the chance of dying from SUDEP is 1 in 1000. However, this risk is greater in patients whose epilepsy is not well-controlled.
Possible Complications When Diagnosed with Sudden Unexpected Death in Epilepsy
The worst possible complication of epilepsy is SUDEP (sudden unexpected death in epilepsy). There are also other risks associated with epilepsy. These include injuries happening during a seizure, aspiration pneumonitis (a lung infection due to breathing in foreign material), drowning, a lengthy period of continuous seizure activity known as ‘status epilepticus’, and toxicity caused by anti-seizure medicine.
In addition to these, people with epilepsy also have a higher chance of developing mental health disorders. These may include learning disabilities or mood disorders such as depression. Other potential problems facing patients are reduced physical activity and the experience of being negatively labeled by society.
Common Risks of Epilepsy:
- SUDEP (Sudden Unexpected Death in Epilepsy)
- Injuries during seizures
- Aspiration pneumonitis (lung infection)
- Drowning
- Status epilepticus (continuous seizure)
- Toxicity from anti-seizure medicine
- Learning disabilities
- Mood disorders such as depression
- Decreased physical activity
- Social stigmatization
Preventing Sudden Unexpected Death in Epilepsy
Sudden unexpected death in epilepsy, often referred to as SUDEP, is a serious complication that can sometimes occur with epilepsy. To prevent SUDEP, it’s important to identify things that might increase the risk of this complication, and then make changes to reduce these risks. Talking with families of epilepsy patients who are at risk for SUDEP has been found to change the way patients behave in a way that reduces their risk of SUDEP.
While these discussions might cause worry for both patients and caregivers, research has shown that patients generally prefer to be informed about their risk of SUDEP. Health organizations such as the United Kingdom National Institute for Clinical Excellence (NICE) and the Scottish Intercollegiate Guideline Network (SIGN) have also recommended that doctors should discuss SUDEP with patients soon after they have been diagnosed with epilepsy.
For these discussions, there are a number of tools available to help doctors assess a patient’s risk of SUDEP. One of these is the SUDEP-7 Risk Inventory. These tools can guide discussions with patients and help to improve their health outcomes by enabling early identification and reduction of SUDEP risks.
