A SYSTEMATIC REVIEW ON EPILEPSY
Epilepsy is a group of neurological diseases characterized by epileptic seizures. Epileptic seizures are episodes that can vary from brief and nearly undetectable to long periods of vigorous shaking. In epilepsy, seizures tend to recur, and have no immediate underlying cause while seizures that occur due to a specific cause are not deemed to represent epilepsy.
The cause of most cases of epilepsy is unknown, although some people develop epilepsy as the result of brain injury, stroke, brain tumor, and substance use disorders. Genetic mutations are linked to a small proportion of the diorder. Epileptic seizures are the result of excessive and abnormal cortical nerve cell activity in the brain. The diagnosis typically involves ruling out other conditions that might cause similar symptoms such as fainting. Additionally, making the diagnosis involves determining if any other cause of seizures is present such as alcohol withdrawal or electrolyte problems. This may be done by imaging the brain and performing blood tests. Epilepsy can often be confirmed with an electroencephalogram (EEG) but a normal test does not rule out the condition
EPILEPSY: A REVIEW
Epilepsy is one of the most common serious neurological disorders affecting about 65 million people globally. It affects 1% of the population by age 20 and 3% of the population by age 75. It is more common in males than females with the overall difference being small. Most of those with the disorder (80%) are in the developing world.
The number of people who currently have active epilepsy is in the range 5–10 per 1,000, with active epilepsy defined as someone with epilepsy who has had a least one seizure in the last five years. Epilepsy begins each year in 40–70 per 100,000 in developed countries and 80–140 per 100,000 in developing countries. Poverty is a risk and includes both being from a poor country and being poor relative to others within one’s country. In the developed world epilepsy most commonly starts either in the young or in the old. In the developing world its onset is more common in older children and young adults due to the higher rates of trauma and infectious diseases. In developed countries the number of cases a year has decreased in children and increased among the elderly between the 1970s and 2003. This has been attributed partly to better survival following strokes in the elderly
People with epilepsy tend to have recurrent seizures (fits). The seizures occur because of a sudden surge of electrical activity in the brain – there is an overload of electrical activity in the brain. This causes a temporary disturbance in the messaging systems between brain cells. During a seizure the patient’s brain becomes “halted” or “mixed up”.
Every function in our bodies is triggered by messaging systems in our brain. What a patient with epilepsy experiences during a seizure will depend on what part of his/her brain that epileptic activity starts, and how widely and quickly it spreads from that area. Consequently, there are several types of seizures and each patient will have epilepsy in his/her own unique way.
The word “epilepsy” comes from the Greek word epi meaning “upon, at, close upon”, and the Greek word Leptos meaning “seizure”. From those roots we have the Old French word epilepsie, and Latin word epilepsia and the Greek words epilepsia and epilepsies.
How common is epilepsy?
Approximately 50 out of every 100,000 people develop epilepsy each year in industrialized nations.
About 50 million people worldwide are said to be affected by epilepsy and seizures.
Epilepsy in USA – according to The Epilepsy Foundation over 3 million Americans are affected by epilepsy and seizures. About 200,000 new cases of seizures and epilepsy occur in the USA each year. 10% of all Americans will experience a seizure some time during their lifetime.
Epilepsy in UK – according to Epilepsy Action 460,000 people in the United Kingdom have epilepsy.
Epilepsy worldwide – according to The National Society for Epilepsy (UK) about 50 million people have epilepsy globally.
Epilepsy can have both genetic and acquired causes, with interaction of these factors in many cases. Established acquired causes include serious brain trauma, stroke, tumours and problems in the brain as a result of a previous infection. In about 60% of cases the cause is unknown. Epilepsies caused by genetic, congenital, or developmental conditions are more common among younger people, while brain tumors and strokes are more likely in older people. Seizures may also occur as a consequence of other health problems; if they occur right around a specific cause, such as a stroke, head injury, toxic ingestion or metabolic problem, they are known as acute symptomatic seizures and are in the broader classification of seizure-related disorders rather than epilepsy itself.
The diagnosis of epilepsy is typically made based on observation of the seizure onset and the underlying cause. Neuroimaging to look at the function of the brain such as electroencephalogram and structure of the brain such as MRI are also usually part of the workup.. While figuring out a specific epileptic syndrome is often attempted, it is not always possible. Video and EEG monitoring may be useful in difficult cases
Epilepsy and life expectancy
Researchers from the University of Oxford and University College London reported in The Lancet in 2013 that premature death is 11 times more common among people with epilepsy compared to 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 15.8% of early deaths. Among these 15.8%, the majority had been diagnosed with a mental disorder.
Epilepsy in developing nations
There are twice as many people with epilepsy in developing nations than industrialized countries. Unfortunately, over 60% of people in poorer nations do not receive proper medical care for epilepsy, researchers from the University of Oxford reported in the journal The Lancet.
The authors added that the burden of epilepsy in developing countries is “under-acknowledged by health agencies”, even though treatments for the disorder are very cost-effective.
Types of seizures
There are three types of diagnoses a doctor might make when treating a patient with epilepsy:
1. Idiopathic – this means there is no apparent cause.
2. Cryptogenic – this means the doctor thinks there is most probably a cause, but cannot pinpoint it.
3. Symptomatic – this means that the doctor knows what the cause is.
There are three descriptions of seizures, depending on what part of the brain the epileptic activity started:
A partial seizure means the epileptic activity took place in just part of the patient’s brain. There are two types of partial seizure:
o Simple Partial Seizure – the patient is conscious during the seizure. In most cases the patient is also aware of his/her surroundings, even though the seizure is in progress.
o Complex Partial Seizure – the patient’s consciousness is impaired. The patient will generally not remember the seizure, and if he/she does, the recollection of it will be vague.
A generalized seizure occurs when both halves of the brain have epileptic activity. The patient’s consciousness is lost while the seizure is in progress.
Secondary Generalized Seizure
A secondary generalized seizure occurs when the epileptic activity starts as a partial seizure, but then spreads to both halves of the brain. As this development happens, the patient loses consciousness.
Symptoms of epilepsy
The main symptoms of epilepsy are repeated seizures. There are some symptoms which may indicate a person has epilepsy. If one or more of these symptoms are present a medical exam is advised, especially if they recur:
• A convulsion with no temperature (no fever).
• Short spells of blackout, or confused memory.
• Intermittent fainting spells, during which bowel or bladder control is lost. This is frequently followed by extreme tiredness.
• For a short period the person is unresponsive to instructions or questions.
• The person becomes stiff, suddenly, for no obvious reason
• The person suddenly falls for no clear reason
• Sudden bouts of blinking without apparent stimuli
• Sudden bouts of chewing, without any apparent reason
• For a short time the person seems dazed, and unable to communicate
• Repetitive movements that seem inappropriate
• The person becomes fearful for no apparent reason, he/she may even panic or become angry
• Peculiar changes in senses, such as smell, touch and sound
• The arms, legs, or body jerk, in babies these will appear as cluster of rapid jerking movements.
The following conditions need to be eliminated as they may present similar symptoms, and are sometimes misdiagnosed as epilepsy:
• A high fever with epilepsy-like symptoms
• Narcolepsy (recurring episodes of sleep during the day and often disrupted nocturnal sleep)
• Cataplexy (a transient attack of extreme generalized weakness, often precipitated by an emotional response, such as surprise, fear, or anger; one component of the narcolepsy quadrad)
• Sleep disorders
• Panic attacks
• Fugue states (a rare psychiatric disorder characterized by reversible amnesia for personal identity)
• Psychogenic seizures (a clinical episode that looks like an epileptic seizure, but is not due to epilepsy. The EEG is normal during an attack, and the behavior is often related to psychiatric disturbance, such as a conversion disorder)
• Breath-holding episodes (when a child responds to anger there may be vigorous crying and subsequent apnea and cyanosis – the child then stops breathing and skin color changes with loss of consciousness)
While many cases are not preventable, efforts to reduce head injuries, provide good care around the time of birth, and reduce environmental parasites such as the pork tapeworm may be effective. Efforts in one part of Central America to decrease rates of pork tapeworm resulted in a 50% decrease in new cases of epilepsy.
Epilepsy is usually treated with daily medication once a second seizure has occurred, but for those at high risk, medication may be started after the first seizure. In some cases, a special diet, the implantation of a neurostimulator, or neurosurgery may be required.
Recent developments on epilepsy treatment from MNT news
Brain stimulator reduces seizures in patients with drug-resistant epilepsy
In 2013, the Food and Drug Administration approved an implantable medical device to treat epilepsy. Now, doctors from the Rush Epilepsy Center in Illinois are the first to couple it with a novel electrode placement planning system, which is enabling the device to better reduce seizures.
The device, called the NeuroPace RNS System, works by using “on-demand” direct stimulation in order to find abnormal electrical activity in the brain and send small bits of electrical stimulation. The doctors from Rush Epilepsy Center explain, by doing this, the device suppresses seizures before they begin.
New pill developed to suppress epilepsy seizures
Within a decade, people with drug-resistant epilepsy may be able to take a pill to suppress seizures as required, in a similar way to how we take painkillers to relieve a headache.
Researchers from University College London (UCL) in the UK believe that the new “on demand” seizure suppressant pill they have developed may offer help to this 30% of epilepsy patients who do not respond successfully to AEDs.
Omega-3 fish oil ‘could reduce seizure frequency for epilepsy patients’
A new study claims epilepsy patients could reduce seizure frequency by consuming low doses of omega-3 fish oil every day. The research team at the University of California-Los Angeles (UCLA) School of Medicine, says their findings may be particularly useful to epilepsy patients who no longer respond to medication.
They publish their findings in the Journal of Neurology, Neurosurgery & Psychiatry.
Music could help treat epilepsy
Researchers are increasingly reporting the therapeutic potential of music. Now, a new study suggests it could be useful for treating epilepsy.
Epilepsy is a brain disorder that causes people to have recurring seizures. The seizures happen when clusters of nerve cells, or neurons, in the brain send out the wrong signals. People may have strange sensations and emotions or behave strangely. They may have violent muscle spasms or lose consciousness.
Epilepsy has many possible causes, including illness, brain injury, and abnormal brain development. In many cases, the cause is unknown.
Doctors use brain scans and other tests to diagnose epilepsy. It is important to start treatment right away. There is no cure for epilepsy, but medicines can control seizures for most people. When medicines are not working well, surgery or implanted devices such as vagus nerve stimulators may help. Special diets can help some children with epilepsy.
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