Epilepsy is a neurological disease that results in abnormal electrical activity in the brain. It mainly affects children, adolescents and the elderly to varying degrees. The causes are in some cases genetic, but in most cases they are not identified.
Definition of epilepsy
Epilepsy is characterized by a sudden increase in electrical activity in the brain, resulting in a temporary disruption of communication between neurons. Usually they are short lived. They can take place either in a specific area of the brain or as a whole. These abnormal nerve impulses can be measured during an electroencephalogram (EEG), a test that records brain activity.
Contrary to popular belief, epileptic seizures are not always accompanied by jerky movements or convulsions. They may indeed be less spectacular. They are then manifested by unusual sensations (such as olfactory or auditory hallucinations, etc.) with or without loss of consciousness, and by various manifestations, such as a fixed gaze or involuntary repetitive gestures.
Important fact: Seizures must repeat for it to be epilepsy. Thus, having had a single seizure in your life does not mean that you have epilepsy. It takes at least two for a diagnosis of epilepsy to be made. An epileptic seizure can appear in several circumstances: head trauma, meningitis, stroke , drug overdose, drug withdrawal, etc.
It is not uncommon for young children to have seizures during a fever flare. Called febrile convulsions , they usually stop around the age of 5 or 6. It is not a form of epilepsy. When such convulsions occur, it is still important to see a doctor.
Causes of Epilepsy
In about 60% of cases, doctors are unable to determine the exact cause of the seizures. It is assumed that about 10% to 15% of all cases would have a hereditary component since epilepsy seems to be more common in some families. Researchers have linked certain types of epilepsy to the malfunction of several genes. For most people, genes are only part of the cause of epilepsy. Certain genes can make a person more sensitive to environmental conditions that trigger seizures.
Note that several years can elapse between the accident and the onset of epilepsy. And remember that for there to be epilepsy, seizures must occur repeatedly and not just once. Stroke is the leading cause of epilepsy in adults over 35 years old.
Infectious diseases: Infectious diseases, such as meningitis, AIDS, and viral encephalitis, can cause epilepsy.
Prenatal injury: Before birth, babies are susceptible to brain damage that could be caused by several factors, such as infection in the mother, poor nutrition, or poor oxygen supply. These brain damage can lead to epilepsy or cerebral palsy.
Developmental disorders: Epilepsy can sometimes be associated with developmental disorders, such as autism and neurofibromatosis.
Who is affected?
In North America, about 1 in 100 people have epilepsy. Among neurological diseases , it is the most common, after migraine. Up to 10% of the world’s population can have a single seizure at some point in their life.
Although it can occur at any age, epilepsy usually starts in childhood or adolescence, or after the age of 65. In older people, the increase in heart disease and stroke increases the risk.
Types of seizures
There are 2 main types of epileptic seizures:
Partial seizures: limited to a specific region of the brain; the patient may be conscious during the seizure (simple partial seizure) or his consciousness may be altered (complex partial seizure). In the latter case, the patient will usually not remember his seizures.
Generalized seizures: spread to all areas of the brain. The patient loses consciousness during the seizure.
Sometimes a seizure, initially partial, spreads to the whole brain and thus becomes generalized. The type of sensation experienced during a seizure gives an indication to the doctor of its origin (frontal lobe, temporal lobe, etc.).
The seizures can be of origin:
Idiopathic: This means that there is no apparent cause.
Symptomatic: This means that the doctor knows the cause. He can also suspect a cause, without identifying it.
There are three descriptions of seizures, depending on the part of the brain where the seizure activity started.
They are limited to a restricted area of the brain.
Simple partial seizures (formerly called “focal seizures”). These attacks usually last a few minutes. During a simple partial seizure, the individual remains conscious.
Symptoms depend on the area of the brain affected. The person may feel tingling, make an uncontrollable tightening movement in a part of the body, experience olfactory, visual or taste hallucinations, or manifest an unexplained emotion.
Symptoms of simple partial seizures can be confused with other neurological disorders, such as migraine, narcolepsy, or mental illness. Careful examination and testing is needed to distinguish epilepsy from other disorders.
Complex partial seizures (formerly called “psychomotor seizures”). During a complex partial seizure, the individual is in an altered state of consciousness.
He does not respond to stimulation and his gaze is fixed. He may have automatisms, that is to say he performs involuntary repetitive gestures such as pulling on his clothes, chattering his teeth, etc. Once the crisis is over, he will not remember at all or very little what happened. He may be confused or fall asleep.
This type of seizure involves the whole brain.
Generalized absences: This is what we used to call the “little evil”. The first attacks of this type of epilepsy usually occur in childhood, from the age of 5 to 10 years. They last a few seconds and may be accompanied by brief fluttering of the eyelids. The person loses contact with his environment, but retains his muscle tone. More than 90% of children with this type of epileptic seizure go into remission from the age of 12.
Tonicoclonic seizures: They were once called “great evil”. It is this type of seizure that is generally associated with epilepsy because of their spectacular appearance. The seizure usually lasts less than 2 minutes. These are generalized convulsions which take place in 2 phases: tonic then clonic.During the tonic phase , the person may cry out and then pass out. Then his body stiffens and his jaw tightens. This phase usually lasts less than 30 seconds.Then in the clonic phase, the person goes into convulsions (uncontrollable, jerky muscle twitches). Breathing, blocked at the onset of the attack, can become very irregular. This usually lasts less than 1 minute.
When the seizure is over, the muscles relax, including those of the bladder and bowels. Later, the person may be confused, disoriented, experience headaches and want to sleep. These effects have a variable duration, from about twenty minutes to several hours. Muscle pains sometimes persist for a few days.
Myoclonic attacks: Rarer, they are manifested by sudden jerking of the arms and legs. This type of seizure lasts from one to a few seconds depending on whether it is a single shock or a series of tremors. They usually do not cause confusion.
Atonic crises: During these uncommon seizures, the person suddenly collapses due to a sudden loss of muscle tone. After a few seconds, she regains consciousness. She is able to get up and walk.
Seizures can lead to bodily injury if the person loses control of their movements.
Individuals with epilepsy can also experience significant psychological repercussions caused, among other things, by the unpredictability of seizures, prejudices, undesirable effects of drugs, etc.
Seizures that are prolonged or that do not end in a return to a normal state must absolutely be treated urgently . They can cause serious neurological sequelae at any age. Indeed, during a prolonged crisis, certain areas of the brain lack oxygen. In addition, damage can be done to neurons due to the release of excitatory substances and catecholamines associated with acute stress.
Some seizures can even turn out to be fatal. The phenomenon is rare and little known. It is known as ” Sudden Unexpected and Unexplained Death in Epilepsy ” (SUDEP). It is believed that an attack could alter the heartbeat or stop breathing. The risk would be higher in epileptics whose seizures are not well treated.
Having a seizure at times can be dangerous for yourself or for others.
Fall: If you fall during a seizure, you risk injuring your head or breaking a bone.
Drowning: If you have epilepsy, you are 15 to 19 times more likely to drown while swimming or in your bathtub than the rest of the population due to the risk of having a seizure in the water.
Car accidents: A seizure that causes loss of consciousness or control can be dangerous if you drive a car. Some countries have driving license restrictions related to your ability to control your seizures.
Emotional health issues: People with epilepsy are more likely to have psychological problems, particularly depression, anxiety and, in some cases, suicidal behavior. The problems can result from difficulties related to the disease itself as well as from the side effects of the drug.
A woman with epilepsy who is planning to become pregnant should take special care. She should see a doctor at least 3 months before conception. For example, the doctor may adjust the medication because of the risk of birth defects with some anti-epileptic drugs. In addition, many anti-epileptic drugs are not metabolised the same way during pregnancy, so the dosage may change. Note that epileptic seizures themselves can endanger the fetus by temporarily depriving it of oxygen.
In general, if the person is well cared for, they can lead a normal life with certain restrictions . For example, driving a car as well as the use of technical equipment or machines in the course of a job may be prohibited at the start of treatment. If the person with epilepsy has not had a seizure for a certain period of time, the doctor can reassess his situation and issue him a medical certificate putting an end to these prohibitions.
Epilepsy can last a lifetime, but some people who have it will eventually have no more seizures. Experts estimate that about 60% of untreated people no longer have seizures within 24 months of their first seizure.
Having had your first seizures at a young age seems to promote remission. About 70% go into remission for 5 years (no seizures for 5 years).
About 20 to 30 percent develop chronic epilepsy (long-term epilepsy).
For 70% to 80% of people in whom the disease persists, drugs are successful in eliminating the seizures.
British researchers have reported that death is 11 times more common in people with epilepsy than in the rest of the population. The authors added that the risk is even greater if a person with epilepsy also has a mental illness. Suicides, accidents and assaults accounted for 16% of early deaths; A majority had been diagnosed with a mental disorder.