Epilepsy

Question 1

What are 3 details about epilepsy?

Answer 1

Epilepsy refers to the abnormal and excessive discharge of a set of neurons in the brain resulting in transitory abnormal neurological phenomena which may include alterations of consciousness or convulsions

Symptoms can range from total sustained muscle contraction (tonus) to violent rhythmic jerking and shaking of all muscle groups (clonus) depending upon which neuronal circuits are misfiring

An epileptic seizure is caused by a crescendo of action potentials in one or more circuits of the brain

Question 2

What are 8 details about the diagnosis of epilepsy?

Answer 2

Epilepsy is diagnosed by confirmation of two or more unprovoked seizures separated by at least 24 hours in an individual

Abnormal findings may also be present in electroencephalogram (EEG) studies and imaging studies of the brain

Since other neurological events can mimic seizures, particularly in children, a careful history must be taken in order to document the exact nature of the “seizure” and arrive at a correct diagnosis

Stimuli that may incite seizure-like symptoms include illness, infection, physical or emotional trauma, medications and use of illicit drugs

True seizures are characterized by inappropriate rhythmic limb movements and/or muscle contractions (clonus) often interrupted by sustained muscle contraction (tonus)

Seizures invariably involve altered consciousness and
unresponsiveness to verbal commands during the episode

Immediately following a seizure, persisting focal findings (delay in restoration of normal speech, sight, hearing, cognition, motor function) can often be used to pinpoint the area of the brain affected

Electroencephalogram (EEG) studies are recommended in the evaluation of individuals with suspected seizures or epilepsy

Question 3

What are 4 details about simple and complex seizures?

Answer 3

Epilepsy is a collection of syndromes and conditions rather than a single disease

A partial or focal seizure refers to a specific localized cerebral area in which the neurons are excessively firing

A simple seizure is one in which there is no loss of consciousness, and a complex seizure is one in which there is impaired awareness or loss of consciousness

Thus, a simple partial seizure refers to localized brain dysfunction without loss of consciousness, whereas a complex partial seizure refers to localized brain
dysfunction and unconsciousness

Question 4

What are 3 details about generalized seizures?

Answer 4

A partial seizure will occasionally evolve into a generalized seizure wherein the patient loses consciousness and manifests other signs and symptoms of widespread neuronal discharge

A generalized seizure is one involving both cerebral hemispheres with widespread cerebral dysfunction and corresponding impact on many motor and cognitive
functions

All generalized seizures involve the loss of consciousness

Question 5

What are the 6 types of seizures?

Answer 5

These are subdivided into six types: absence (petit mal), myoclonic, clonic, tonic, atonic and tonic-clonic (grand mal) seizures

Question 6

What are 2 details about absence (petit mal) seizures?

Answer 6

Absence (petit mal) seizures cause a brief loss of consciousness for a few seconds without other symptoms

Such seizures typically interrupt normal childhood activity and may reoccur several times throughout the day

Question 7

What is 1 detail about myoclonic vs. clonic seizures?

Answer 7

Myoclonic seizures consist of sporadic “jerking” muscle contractions of very short duration whereas clonic seizures involve inappropriate repetitive rhythmic
movements simultaneously occurring on both sides of the body

Question 8

What is 1 detail about tonic vs. atonic seizures?

Answer 8

Tonic seizures are characterized by sustained contraction of muscles whereas atonic seizures involve the loss of muscle tone particularly in the arms and legs
which often results in a fall

Question 9

What are 2 details about grand mal seizures?

Answer 9

The most dramatic of the generalized seizures is the grand mal seizure, in which the patient first loses consciousness and manifests generalized contraction of all muscles (the tonic phase) for 30 to 60 seconds followed by violent uncontrolled spasmodic muscle contractions (the clonic phase) for 30 to 60 seconds, after which the patient enters into a deep coma (the postictal phase) that may last up to 30 minutes.

Grand mal seizures can be fatal and are characterized by incontinence, tongue biting, convulsions, and accidental injury

Question 10

What are 3 details about status epilepticus?

Answer 10

A catastrophic event in a patient with epilepsy is the occurrence of status epilepticus

This life-threatening condition is defined as the presence of intense unrelenting seizure activity lasting longer than 30 minutes

Status epilepticus occurs in about 1 in 5 patients who have been diagnosed with epilepsy

Question 11

What are 2 details about the classification of seizures?

Answer 11

Accurate classification according to seizure type involves testing by an electroencephalogram (EEG) which records tracings of brain waves from different regions of the brain

Such tests are often unavailable in epidemiologic investigations of epilepsy that are conducted in the field

Question 12

What are 5 details about the treatment and prognosis of epilepsy?

Answer 12

The cornerstone of epileptic treatment is administration of anticonvulsant and antipsychotic medications antecedent to seizures or during times of high stress

In the USA, there are more than 20 medications that are
approved for the treatment of epilepsy

Recent studies suggest that with early diagnosis and accurate differentiation between generalized and partial seizures coupled with administration of targeted anticonvulsant medications as needed to inhibit seizures and minimize side effects, the majority of patients with disease are able to achieve sustained freedom from seizure activity

In patients with symptomatic epilepsy (with known etiology), effective treatment involves not only the management of seizure activity but also intervention to
address the underlying pathology

Early epilepsy diagnosis and monotherapy has also proven successful in rural communities

Question 13

What are 3 details about the risk factors for epilepsy?

Answer 13

The risk factors for early onset disease during childhood and late onset disease in the elderly are dramatically different

Young patients develop epilepsy as a consequence of genetic predisposition, trauma, infection whereas elderly patients develop epilepsy secondary to cerebrovascular disease (stroke), metabolic conditions (type 2 diabetes), cancer, other neurodegenerative conditions (Alzheimer’s disease) and alcohol abuse and/or withdrawal

About 30% of first acute seizures among the elderly are status epilepticus requiring emergency care

Question 14

What are 2 details about DALYs due to epilepsy?

Answer 14

The Disability Adjusted Life Years (DALY) that are lost due to epilepsy reflect a public health burden of tremendous dimensions

Rates are highest in impoverished nations where there is little access to treatment

Question 15

What are 3 details about the global burden of epilepsy?

Answer 15

The World Health Organization reports that about 50 million people worldwide have epilepsy

Approximately 40 million of those afflicted reside in
developing nations with little or no access to treatment.

About 30 million people with this condition receive no
medication

Question 16

What are 3 details about the prevalence of epilepsy?

Answer 16

Epilepsy is often a lifelong disorder that persists in an
individual for many decades

Annual prevalence rates are therefore much higher than the incidence rates, varying widely worldwide from 1 to 20 per 1,000 with a median rate of about 7 per 1,000

High annual prevalence rates have been reported for
impoverished nations in sub-Saharan Africa and Latin America (15 to 20 per 1,000) whereas much lower rates have been reported for industrialized nations

Question 17

What are 9 details about the epilepsy treatment gap?

Answer 17

Results of a recent world wide survey revealed a wide range of treatment gaps from 6% in Singapore to 100% in Bolivia

Treatment gaps of less than 10% were observed for patient populations in Taiwan, Norway, Singapore, the UK, Ireland, the USA, and selected populations in Argentina, Brazil and France

In sharp contrast, treatment gaps greater than 95% were found in rural China, Ethiopia, the Gambia, the Lao People’s Republic, Nigeria, Pakistan, Panama, Togo, Uganda, the United Republic of Tanzania and Zambia

The epilepsy treatment gap, defined as the proportion of people with active epilepsy who require treatment but do not receive it, has been proposed as a useful parameter to compare access to and quality of care for epilepsy patients across populations

Prior anecdotal and descriptive estimates suggest that the treatment gap is much higher in low-income than high-income countries

Wide variability was also noted within some countries

For example, treatment gaps in India ranged from 22% for patients in urban areas to 90% for patients living in rural villages

The results clearly reflect dramatic global disparities in the care and treatment of epilepsy patients

Treatment gaps for active epilepsy exceed 75% in most low-income countries and 50% in most middle-income countries, whereas high-income countries have treatment gaps of less than 10%

Question 18

What are 3 details about epilepsy mortality?

Answer 18

Individuals with epilepsy die from four major causes: status epilepticus (often due to lack of anticonvulsant medications), suicide associated with depression, trauma associated with seizures, and sudden unexpected death in epilepsy

Those at highest risk for epilepsy-related deaths usually have underlying neurological impairment or poorly controlled seizures whereas those with mild to moderate epilepsy are at much lower risk of epilepsy-related death

The case fatality and mortality rates reported for epileptic patients are highest in developing nations and rural areas where there is little access to treatment

Question 19

What are 2 details about epilepsy risk factors?

Answer 19

Risk factors for circumstantial epilepsy include age (epilepsy is most commonly diagnosed in children and elderly adults), male gender, head trauma, stroke, cardiovascular disease, encephalitis (infection of the brain), brain tumors and other cancers, certain metabolic conditions, alcohol and other drugs

Any exposure that causes brain damage or interrupts normal brain function should be regarded as a potential risk factor for the development of epileptic seizures

Question 20

What are 4 details about catamenial epilepsy?

Answer 20

Catamenial epilepsy is when partial seizures cluster around certain phases of a woman’s menstrual cycle.

Three major types of catamenial epilepsy have been defined: perimenstrual, periovulatory, and periluteal.
In each type, seizure activity is increased by about 2-fold during the corresponding time of the menstrual cycle

Estrogen replacement therapy has traditionally been used in menopausal women with epilepsy to alleviate their menopausal symptoms such as hot flashes and
vaginal dryness.

However, recent studies suggest that hormone therapy may increase seizure activity

Question 21

What are 5 details about cysticercosis and seizures?

Answer 21

Cysticercosis is a systemic infection caused by the pork tapeworm Taenia solium

Humans acquire the parasite by ingesting its eggs in food or water contaminated by feces of infected individuals

Neurocysticercosis is caused by infection of the central nervous system and/or brain by the larval stage of Taenia solium

This condition is a major cause of neurologic disease in developing countries of Latin America, South America, Africa and Asia

Neurocysticercosis is the underlying cause of many seizures in these populations, and is primarily responsible for the higher incidence of epilepsy in developing versus industrialized nations

Question 22

What are 2 details about weight and seizures?

Answer 22

Severely underweight subjects with BMI less than 18.5 and gravidly obese subjects with BMI greater than 40 have been found to have elevated seizure rates
(RR=1.6 and 1.8, respectively)

Findings suggest that individuals at the extremes of body mass are susceptible to seizure development

Question 23

What are 4 details about type II diabetes and seizures?

Answer 23

Patients with type 2 diabetes have been found to be at increased risk for the development of acute epileptic seizures in a number of studies

In patients with type 2 diabetes, the onset of epileptic seizure is often associated with nonketotic hyperglycemia

Several types of epileptic seizures have been reported in patients with nonketotic hyperglycemia

Early recognition and swift correction of the condition by administration of insulin and rehydration are essential to prevent serious morbidity and mortality

Question 24

What are 4 details about strokes and seizures?

Answer 24

Stroke is a major risk factor for the development of epileptic seizures

Population-based studies have found 20 to 40-fold increases in seizure risk relative to the general population

Status epilepticus can also occur following a stroke, involving 31% of stroke patients with seizures in one large study

Status epilepticus was the initial seizure type in more than half of these patients

Question 25

What are 6 details about alcohol consumption seizures?

Answer 25

Meta-analysis of 18 published studies quantified the association between alcohol consumption and epilepsy risk Results reveal a significant dose response in the risk of epilepsy with increasing alcohol consumption The data suggest that a threshold level of about 4 alcoholic drinks per day (48 g of pure alcohol) is sufficient to produce a 2 to 3-fold elevation in the risk (Samokhvalov et al., 2010) Various hypotheses have been advanced to explain the link between alcohol abuse and epilepsy risk These include alcohol toxicity to neurons, hypoxia due to alcohol-related cerebrovascular disease, brain damage due to traumatic injury, and a “kindling theory” The kindling theory suggests that repeated withdrawal from alcohol including natural withdrawal during sleep over many years gradually reduces the epileptogenic threshold

Question 26

What are 4 details about toxocariasis and epilepsy?

Answer 26

Human toxocariasis is another parasitic zoonotic infection found primarily in populations of developing nations Infection is caused by Toxocara canis, a common roundworm found in dogs and cats Humans ingest eggs of the parasite in contaminated food and fomites The larvae of Toxocara canis can migrate into the central nervous system and cause neurologic symptoms including epilepsy

Question 27

What are 3 details about river blindness and epilepsy?

Answer 27

Onchocerciasis, also known as river blindness, is a parasitic infection caused by Onchocerca volvulus, a small nematode (roundworm) that is transmitted to humans through the bite of a blackfly of the genus Simulium The larval nematodes spread to many tissues of the body including the retina of the eye and in some cases the brain The worms carry a symbiotic bacteria, Wolbachia pipientis, and when the worms die, Wobachia symbionts are released triggering a host immune response that causes intense itching and necrosis of infected tissues

Question 28

What are 4 details about seizure categorization?

Answer 28

Types of seizure are categorized according to the location of dysfunctional neuronal circuits in the brain and the extent of consciousness with corresponding impact on motor and cognitive function Simple seizures are subclassified according to the profile of symptoms: motor impairment involving muscle contraction and rigidity; cognitive impairment affecting vision, hearing, smell, taste or touch; and memory or emotional disturbances. Complex partial seizures are characterized by impaired awareness of surroundings or loss of consciousness. Other characteristics include automatisms such as lip smacking, chewing, fidgeting and other inappropriate involuntary repetitive movements.