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The causes of epilepsy in childhood vary. In about ⅔ of cases, it is unknown.
- Unknown 67.6%
- Congenital 20%
- Trauma 4.7%
- Infection 4%
- Stroke 1.5%
- Tumor 1.5%
- Degenerative .7%
Onset is between 3 and 15 years of age with a mean of around 8. Both sexes are equally affected. The disorder accounts for about 2–7% of benign childhood focal seizures.
People with epilepsy are at an increased risk of death. This increase is between 1.6 and 4.1 fold greater than that of the general population and is often related to: the underlying cause of the seizures, status epilepticus, suicide, trauma, and sudden unexpected death in epilepsy (SUDEP). Death from status epilepticus is primarily due to an underlying problem rather than missing doses of medications. The risk of suicide is increased between two and six times in those with epilepsy. The cause of this is unclear. SUDEP appears to be partly related to the frequency of generalized tonic-clonic seizures and accounts for about 15% of epilepsy related deaths. It is unclear how to decrease its risk. The greatest increase in mortality from epilepsy is among the elderly. Those with epilepsy due to an unknown cause have little increased risk. In the United Kingdom, it is estimated that 40–60% of deaths are possibly preventable. In the developing world, many deaths are due to untreated epilepsy leading to falls or status epilepticus.
Epilepsy is a relatively common disorder, affecting between 0.5-1% of the population, and frontal lobe epilepsy accounts for about 1-2% of all epilepsies. The most common subdivision of epilepsy is symptomatic partial epilepsy, which causes simple partial seizures, and can be further divided into temporal and frontal lobe epilepsy. Although the exact number of cases of frontal lobe epilepsy is not currently known, it is known that FLE is the less common type of partial epilepsy, accounting for 20-30% of operative procedures involving intractable epilepsy. The disorder also has no gender or age bias, affecting males and females of all ages. In a recent study, the mean subject age with frontal lobe epilepsy was 28.5 years old, and the average age of epilepsy onset for left frontal epilepsy was 9.3 years old whereas for right frontal epilepsy it was 11.1 years old.
Although the theory is controversial, there is a link between febrile seizures (seizures coinciding with episodes of fever in young children) and subsequent temporal lobe epilepsy, at least epidemiologically.
The prognosis of ICOE-G is unclear, although available data indicate that remission occurs in 50–60% of patients within 2–4 years of onset. Seizures show a dramatically good response to carbamazepine in more than 90% of patients. However, 40–50% of patients may continue to have visual seizures and infrequent secondarily generalized convulsions, particularly if they have not been appropriately treated with antiepileptic drugs.
The prognosis for Rolandic seizures is invariably excellent, with probably less than 2% risk of developing absence seizures and less often GTCS in adult life.
Remission usually occurs within 2–4 years from onset and before the age of 16 years. The total number of seizures is low, the majority of patients having fewer than 10 seizures; 10–20% have just a single seizure. About 10–20% may have frequent seizures, but these also remit with age.
Children with Rolandic seizures may develop usually mild and reversible linguistic, cognitive and behavioural abnormalities during the active phase of the disease. These may be worse in children with onset of seizures before 8 years of age, high rate of occurrence and multifocal EEG spikes.
The development, social adaptation and occupations of adults with a previous history of Rolandic seizures were found normal.
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 causes of TLE include mesial temporal sclerosis, traumatic brain injury, brain infections, such as encephalitis and meningitis, hypoxic brain injury, stroke, cerebral tumours, and genetic syndromes. Temporal lobe epilepsy is not the result of psychiatric illness or fragility of the personality.
The age of onset ranges from 1 to 14 years with 75% starting between 7–10 years. There is a 1.5 male predominance, prevalence is around 15% in children aged 1–15 years with non-febrile seizures and incidence is 10–20/100,000 of children aged 0–15 years
Though there is limited evidence, outcomes appear to be relatively poor with a review of outcome studies finding that two thirds of PNES patients continue to experience episodes and more than half are dependent on social security at three-year followup. This outcome data was obtained in a referral-based academic epilepsy center and loss to follow-up was considerable; the authors point out ways in which this may have biased their outcome data. Outcome was shown to be better in patients with higher IQ, social status, greater educational attainments, younger age of onset and diagnosis, attacks with less dramatic features, and fewer additional somatoform complaints.
Like many other types of seizures, gelastic seizures are hard to control for an extended period of time. The best outlook is for children suffering the seizures due to a benign tumor in their hypothalamus. The removal of these tumors can be effective not only for the frequency of the seizures, but also the behavioral and cognitive symptoms that come along with the syndrome. Cases have also been described where that antiepileptic drugs have stopped seizures fully.
Epilepsy has a substantial impact on the quality of life of the individuals that are afflicted with it. Physicians and researchers are coming to understand that the impact on the quality of life of the patient is as important as the effects of the seizures. Quality of life questionnaires and other assessment tools have been created to help quantify quality of life for individual patients. They consider such factors as physical health (including numbers and severity of seizures, medication side effects etc.), mental health, social relationships, lifestyle, role activities and life fulfillment. A Center for Disease Control study reported that seizure sufferers were more likely to have lower education levels, higher unemployment, higher levels of pain, hypersomnia/insomnia, increased psychological distress and social isolation/connection issues. Some of the issues which impact quality of life for people with epilepsy are: ability to drive and travel, the ability to date, marry and have children, the ability to have a job and independence, the ability to have an education and learn, and the ability to have good health and mental functioning. Future research is needed to find ways of not only controlling frontal lobe seizures, but of also addressing the specific quality-of-life issues that plague those with frontal lobe epilepsy.
- Driving and transportation restrictions
- Driving and travel restrictions are one of the greatest limitations that epileptic patients experience. Laws restricting driving privileges vary greatly in the United States as well as across the world. In the United States, 28 states require a patient to be seizure free for fixed periods of time ranging from 3–12 months. However, research done by Johns Hopkins University showed that there was no difference in seizure-related fatal crash rates in states with 3-month restrictions versus states with 6-12 month seizure-free restrictions. In 23 states, the restrictions and seizure free periods vary depending on the type of epilepsy and the individual case and in 13 states physicians were responsible for determining whether their patients should be allowed to drive. In 6 of those 13 states physicians could be held legally liable for their decisions regarding their epileptic patients’ driving capabilities. In many states, patients can also be legally liable for accidents, injury, damage and death caused by seizure related accidents.
- One of the major arguments in favor of restricting the licensing of epileptic drivers is the concern for public safety. However, the Johns Hopkins study showed that in a particular 2 year timeframe only 0.2% of fatal crashes occurred as a result of seizures. Alcohol related crash fatalities caused 156 times more driver deaths than seizure related crashes and young drivers between the ages of 16 and 24 were 123 times more likely to die in a fatal crash caused by their inexperience than an epileptic driver was to die in a crash that resulted from a seizure.
- Frontal lobe epileptic seizures unlike other epileptic seizures create symptoms that are as dangerous as loss of consciousness and much more difficult to discern from other problems such as drug and alcohol abuse, psychiatric disorders and disobedience. Jerking movements/lack of motor control, pedaling, pelvic thrusting, lapses in cognitive functioning and other hallmark symptoms of frontal lobe epileptic seizures all create dangerous behavior behind the wheel. Studies have not been done to date to determine the differential risk posed by drivers with frontal lobe epilepsy relative to the general epileptic population.
- Hormones and pregnancy issues
- Hormonal changes and pregnancy can shift seizure activity and the use of antiepileptic drugs can alter the efficacy of hormones as well as cause congenital malformations in fetuses. Seizure control in pregnant women is very important to the welfare of both the developing fetus and the mother. Hormonal shifts at puberty, with birth control and at menopause can also cause changes in the frequency and severity of seizures and must be closely monitored. Increased seizure activity is reported by 50% of women during the course of the pregnancy due to changing levels of hormones, fluids, salts and absorption and elimination of medications.
- Employment
- A report by the Epilepsy Foundation noted that the unemployment rate amongst people with epilepsy is 25% and in patients whose seizures are poorly controlled the rate jumps to 50%. Even though people with epilepsy are protected under The Americans with Disabilities Act, employment discrimination and high rates of unemployment due to employer attitudes still exist. A study in the UK showed that 16% of employers surveyed felt there were no jobs in their company suitable for people with epilepsy and that 21% felt that employing an epileptic would be a “major issue”. Fifty percent of the employers said they had a high concern regarding employing people with epilepsy with most citing safety concerns/workplace accidents as their major issue. Patients with frontal lobe epilepsy may be particularly prone to being discriminated against in employment and subject to higher rates of termination due to the unusual motor symptoms, speech, vocal outbursts and cognitive/judgment symptoms displayed during frontal lobe seizures. Frontal lobe seizures also tend to come on suddenly and progress rapidly making it difficult for an employer to control the exposure of the seizure to others.
- Education, learning and cognitive function
- Patients with frontal lobe epilepsy will likely also experience issues with learning and education. Many factors contribute to these issues including the impact of anticonvulsant medications. Anticonvulsant medications cause patients to feel “foggy” and sluggish. Drugs such as Topiramate cause problems such as mental blunting, word retrieval difficulties and irritability. Phenobarbital, Primidone and Vigabatrin can cause depression and suicidal tendencies. Stress and lack of sleep during exam periods can trigger seizures and many school sports teams restrict or ban people with epilepsy from sports for safety and liability reasons. Frontal lobe epilepsy sufferers also exhibit dysfunctional cognitive skills and memory issues which can make learning challenging. Research has shown that frontal lobe epilepsy has a greater negative impact than other forms of epilepsy on cognitive functioning. People with frontal lobe epilepsy show decreased cognitive capabilities in the following areas: humor appreciation, recognition of emotional expressions, response selection/initiation and inhibition, hyperactivity, conscientiousness, obsession, addictive behavior, motor coordination and planning, attention span, performance speed, continuous performance without intrusion and interference errors, copying and recall, concept formation, anticipatory behavior, memory span, working memory, executive planning, visuo-spatial organization, mental flexibility, conceptual shift, problem solving, programming of complex motor sequences, impulse control, judgment and forecasting of consequences.
- Physical health and risk of other conditions
- Patients with epilepsy face a greater risk of accidents, injury and other medical conditions than the general population. A European study showed that people with epilepsy were at greater risk for accidental injuries related to seizures such as concussions, abrasions and wounds and reported more hospitalizations and medical action than the general population. Other studies have shown that people with epilepsy are at a greater risk of seizure related drowning, suffocation, broken bones and burns and more likely to die in a fatal automobile crash.
- Epilepsy Ontario reports that people with epilepsy are also more likely to have other conditions than the general population such as: 30% of autistic children have epilepsy, 33% of cerebral palsy patients have epilepsy, 15-20% of fragile X syndrome patients have epilepsy, 50% of children with learning disabilities will have some form of epilepsy, 3-10% of patients with Lennox-Gastaut syndrome will have epilepsy, 80% of children with Rett syndrome will have epilepsy and 80% of patients with Tuberous Sclerosis will have epilepsy.
- Mental and emotional health
- Epileptic patients are more prone to suffer psychological and social dysfunction than individuals that do not have epilepsy. They report higher levels of anxiety and stress due to social isolation, discrimination, the unpredictability of their seizures and people’s reactions to them as well as fear of injury, death and brain damage from their seizures. Anticonvulsants can also result in lower functioning, depression, sluggishness and suicidal thoughts. Approximately 20% of people with epilepsy are depressed and the rate of suicide amongst people with epilepsy is 5 times the rate in the general population.
- People with frontal lobe epilepsy experience more significant social effects because the manifested symptoms are more unusual. Symptoms such as screaming, bicycling limbs, pelvic thrusting, inhibition control and other outbursts can be particularly embarrassing and isolating for the patient.
Most people with PNES (75%) are women, with onset in the late teens to early twenties being typical.
Some studies have reported an elevated frequency of childhood abuse in people with PNES. However, others that have controlled for other demographic factors have failed to find a higher rate of reported childhood abuse than in a comparable groups with organic disease (usually epilepsy).
A number of studies have also reported a high incidence of abnormal personality traits or personality disorders in people with PNES such as borderline personality. However, again, when an appropriate control group is used, the incidence of such characteristics it not always higher in PNES than in similar illnesses arising due to organic disease (e.g., epilepsy).
Other risk factors for PNES include having a diagnosis of epilepsy, having recently had a head injury or recently undergone neurosurgery.
Genetics may play a role in the risk that a person will develop PTE; people with the ApoE-ε4 allele may be at higher risk for PTE. The haptoglobin Hp2-2 allele may be another genetic risk factor, possibly because it binds hemoglobin poorly and thus allows more iron to escape and damage tissues. However, most studies have found that having family members with epilepsy does not significantly increase the risk of PTS, suggesting that genetics are not a strong risk factor.
Between 10 and 30% of people who have status epilepticus die within 30 days. The great majority of these people have an underlying brain condition causing their status seizure such as brain tumor, brain infection, brain trauma, or stroke. However, people with diagnosed epilepsy who have a status seizure also have an increased risk of death if their condition is not stabilized quickly, their medication and sleep regimen adapted and adhered to, and stress and other stimulant (seizure trigger) levels controlled.
However, with optimal neurological care, adherence to the medication regimen, and a good prognosis (no other underlying uncontrolled brain or other organic disease), the person—even people who have been diagnosed with epilepsy—in otherwise good health can survive with minimal or no brain damage, and can decrease risk of death and even avoid future seizures.
Consistent risk factors include:
- Severity of seizures, increased refractoriness of epilepsy and presence of generalized tonic-clonic seizures: the most consistent risk factor is an increased frequency of tonic–clonic seizures.
- Poor compliance. Lack of therapeutic levels of anti-epileptic drugs, non-adherence to treatment regimens, and frequent changes in regimens are risk factors for sudden death.
- Young age, and early age of seizures onset.
- Male gender
- Poly-therapy of epilepsy. It remains unclear whether this is an independent risk factor or a surrogate marker for severity of epilepsy.
- Being asleep during a seizure is likely to favour SUDEP occurrence.
Most children who develop epilepsy are treated conventionally with anticonvulsants. In about 70% of cases of childhood epilepsy, medication can completely control seizures. Unfortunately, medications come with an extensive list of side effects that range from mild discomfort to major cognitive impairment. Usually, the adverse cognitive effects are ablated following dose reduction or cessation of the drug.
Medicating a child is not always easy. Many pills are made only to be swallowed, which can be difficult for a child. For some medications, chewable versions do exist.
The ketogenic diet is used to treat children who have not responded successfully to other treatments. This diet is low in carbohydrates, adequate in protein and high in fat. It has proven successful in two thirds of epilepsy cases.
In some cases, severe epilepsy is treated with the hemispherectomy, a drastic surgical procedure in which part or all of one of the hemispheres of the brain is removed.
The more severe the brain trauma is, the more likely a person is to suffer late PTE. Evidence suggests that mild head injuries do not confer an increased risk of developing PTE, while more severe types do. In simple mild TBI, the risk for PTE is about 1.5 times that of the uninjured population. By some estimates, as many as half of sufferers of severe brain trauma experience PTE; other estimates place the risk at 5% for all TBI patients and 15–20% for severe TBI. One study found that the 30-year risk of developing PTE was 2.1% for mild TBI, 4.2% for moderate, and 16.7% for severe injuries, as shown in the chart at right.
Focal seizures (also called partial seizures and localized seizures) are seizures which affect initially only one hemisphere of the brain. The brain is divided into two hemispheres, each consisting of four lobes – the frontal, temporal, parietal and occipital lobes. A focal seizure is generated in and affects just one part of the brain – a whole hemisphere or part of a lobe. Symptoms will vary according to where the seizure occurs. In the frontal lobe symptoms may include a wave-like sensation in the head; in the temporal lobe, a feeling of déjà vu; in the parietal lobe, a numbness or tingling; and in the occipital lobe, visual disturbance or hallucination.
The estimated annual incidence of TGA varies from a minimum of 2.9 cases per 100,000 population (in Spain) and 5.2 per 100,000 (in USA), but among people aged over 50, the rate of TGA incidence is reported to range from approximately 23 per 100,000 (in a US population) to 32 per 100,000 (in a population in Scandinavia).
TGA is most common in people between age 56 and 75, with the average age of a person experiencing TGA being approximately 62.
TGA attacks are associated with some form of precipitating event in at least one-third of cases. The most commonly cited precipitating events include vigorous exercise (including sexual intercourse), swimming in cold water or enduring other temperature changes, and emotionally traumatic or stressful events. There are reports of TGA-like conditions following certain medical procedures and disease states. One study reports two cases of familial incidence (in which two members of the same family experienced TGA), out of 114 cases considered. This indicates the possibility that there could be a slight familial incidence.
If the definition of a precipitating event is widened to include events days or weeks earlier, and to take in emotionally stressful burdens such as money worries, attending a funeral or exhaustion due to overwork or unusual childcare responsibilities, a large majority, over 80%, of TGA attacks are said to correlate with precipitating events.
The role of psychological co-factors has been addressed by some research. It is the case that people in a state of TGA exhibit measurably elevated levels of anxiety and/or depression. Emotional instability may leave some people vulnerable to stressful triggers and thus be associated with TGA. Individuals who have experienced TGA, compared with similar people with TIA, are more likely to have some kind of emotional problem (such as depression or phobias) in their personal or family history or to have experienced some kind of phobic or emotionally challenging precipitating event.
In the United States, about 40 cases of SE occur annually per 100,000 people. This includes about 10–20% of all first seizures.
A person who suffers from epilepsy regardless of whether it is nocturnal or not, can be categorized into two different types of epilepsy either being generalized, or partial. A generalized epilepsy syndrome is associated with an overall hyperactivity in the brain, where electrical discharges occur all over the brain at once; this syndrome often has a genetic basis. While generalized epilepsy occurs all over the brain, partial epilepsy consists of a regional or localized hyperactivity, which means that the seizures occur conversely in one part of the brain or several parts at once.
Like other forms of epilepsy, nocturnal epilepsy can be treated with anti-convulsants.
Despite the effectiveness of anti-convulsants in people who suffer from nocturnal epilepsy, the drugs are shown to disrupt a person's sleeping structure. This may cause concern in people who suffer specifically from nocturnal epilepsy because undisrupted sleep is important for these people, as it lowers the likeliness of epileptic symptoms to arise.
One particular study by V. Bradley and D. O'Neill analysed the different forms of epilepsy, including nocturnal epilepsy and its relationship with sleep. They found that some patients only experienced epileptic symptoms while they are asleep (nocturnal epilepsy), and that maintaining good sleep helped in reducing epileptic symptoms. Another study determined that anti-convulsant medications can minimize epilepsy not just in people who are awake, but also in people who are asleep. However, some of these anti-convulsant medications did also have adverse effects on subjects' sleeping structures, which can exacerbate epileptic symptoms in people who suffer from nocturnal epilepsy.
To minimize epileptic seizures in these people, it is important to find an anti-convulsant medication that does not disrupt a person's sleeping structure. The anti-convulsant medications that were tested to meet this criteria are: phenobarbital, phenytoin, carbamazepine, valproate, ethosuximide, felbamate, gabapentin, lamotrigine, topiramate, vigabatrin, tiagabine, levetiracetam, zonisamide, and oxcarbazepine. Oxcarbazepine is shown to have the least amount of adverse effects on sleep. Another study shows that it enhances slow wave-sleep and sleep continuity in patients with epilepsy.