WHAT IS EPILEPSY?

 

Epilepsy affects 3 million Americans and 20% develop epilepsy before the age of five - a critical period of brain development. Surprisingly, epilepsy affects more people than cerebral palsy, multiple sclerosis, muscular dystrophy and Parkinson's Disease combined.
Before dealing with epilepsy firsthand, we thought, like many, that it was a manageable, treatable condition. For some people, this is true. But for many others, like Camille, epilepsy is defined by intractable seizures, impaired mental and motor functioning and life-threatening risks. Approximately 40,000 people die each year from epilepsy and related causes and one million people currently live with uncontrolled (intractable) seizures. Camille suffers from a rare form of epilepsy called Infantile Spasms (also known as West Syndrome). The estimated incidence is 1 in every 3,225 live births, which translates into about 1,300 new cases in the United States each year.

 

Epilepsy research has historically been underfunded. Theories abound as to the cause. Part of the issue may rest with several wide-spread misconceptions -- that epilepsy is a relatively benign syndrome which can be controlled and that seizures do not cause brain damage. Many of the one million people who suffer from intractable (uncontrollable) seizures have been hesitant to speak out because of the stigma associated with this condition. Until recently, much of the focus has been on living with Epilepsy and managing the condition. The medical community is just beginning to focus more resources on curing Epilepsy and eliminating its devastation, though much remains to be done.

 

Epilepsy affects 3 million Americans of all ages at a cost of $12.5 billion dollars annually. Yet the syndrome is woefully underfunded. In 2003, the NIH spent only $38 per patient affected by epilepsy while multiple sclerosis and Parkinson’s Disease received $248 and $230 per person, respectively. Over the four year period from 1999 to 2003, funding for Parkinson’s Disease increased by 74%, funding for multiple sclerosis increased by 59% and funding for Epilepsy, which afflicts substantially more people, increased only 6%.
With appropriate advocacy and awareness, these funding statistics can and must be changed.

 

Key Facts About Epilepsy
Epilepsy affects 3 million Americans, more Americans that cerebral palsy, multiple sclerosis and Parkinson's Disease combined.
More than one million Americans live with uncontrolled seizures and children face particular devastation.
Ongoing seizure activity damages the developing brain and can result in mental retardation, severe functional limitations and even death.  
Early diagnosis and treatment is critical to maximizing long-term prognosis.  

OVERVIEW
Epilepsy is a serious disorder, consisting of recurring seizures that affect awareness, sensation, or movement.  Epilepsy is not a single disease or disorder but a family of more than 40 syndromes that affect 3 million Americans and 50 million people worldwide have epilepsy.  There are more than 20 kinds of seizures.

 

While successful treatment enables many to live productive lives, many Americans (approximately one million) continue to have seizures despite all efforts to control them. Many of these are children, who can experience up to hundreds of seizures a day. The impact on the developing brain from this uncontrolled activity ranges from learning disabilities to retardation, and in a disturbingly large number of patients, even death. There is also an increasingly large incidence of new onset epilepsy in the aging population as a result of strokes, brain tumors and Alzheimers Disease.


WHAT IS EPILEPSY? When a person has had two or more seizures which have not been provoked by specific events such as trauma, infection, fever or chemical change, he or she is considered to have epilepsy.


WHAT IS A SEIZURE? A seizure is a sudden surge of electrical activity in the brain that usually affects how a person feels or acts for a short time. Seizures are not a disease in themselves. Instead, they are a symptom of many different disorders that can affect the brain. Some seizures can hardly be noticed, while others are totally disabling. The seizures in epilepsy may be related to a brain injury or a family tendency, but often the cause is completely unknown. The word "epilepsy" does not indicate anything about the cause or severity of the person's seizures.


WHAT CAUSES EPILEPSY? Epilepsy may develop because of an abnormality in brain wiring, an imbalance of nerve signaling chemicals (neurotransmitters), or a combination of these factors. Causes of epilepsy may include head injuries, brain tumors, lead poisoning, certain genetic diseases and some infectious diseases. However, in more than half the patients with epilepsy, the cause is still unknown.

STATISTICS
HOW COMMON IS EPILEPSY and HOW MANY ARE AFFECTED?
Epilepsy can strike at any time in one's life. About 3 million people in the USA have epilepsy. Anyone can develop epilepsy at any age, but 30% of epilepsy cases are children under 18 years of age and 20% develop epilepsy before the age of 5.  Each year, 120,000 children seek medical attention because of a first or newly diagnosed seizure.
There are more people with epilepsy in the US than the combined number of people with multiple sclerosis, cerebral palsy, muscular dystrophy and Parkinson's Disease . Epilepsy can occur as a single condition or may accompany other conditions affecting the brain, such as cerebral palsy, mental retardation, autism, Alzheimer's disease, and traumatic brain injury.

DEATH and EPILEPSY
Experts estimate that prolonged seizures (status epilepticus) are the cause of 22,000 to 42,000 deaths in the USA each year. In a major study of status epilepticus, 42% of deaths occurred in individuals with a history of epilepsy.
There are two types of mortality in epilepsy: accidents and sudden unexplained death (SUDEP). SUDEP is a serious problem and occurs mostly in intractable epilepsy, epilepsy which is not controlled by medication. Major risk factors for SUDEP are: more than three (3) generalized tonic-clonic seizures per year, more than two (2) anticonvulsant medications required to treat the seizures or moderately severe learning disability.

FACTS ABOUT EPILEPSY THAT MAY SURPRISE YOU
1. Epilepsy is a major health problem, affecting more people than multiple sclerosis, cerebral palsy, muscular dystrophy and Parkinson's Disease combined.
2.     Over 50 million people worldwide have been diagnosed with epilepsy, with 3 million people in the United States.
3. More than one million Americans suffer from uncontrolled seizures.
4.     In the US, almost 80% of patients report their seizures are inadequately controlled, or controlled only at the cost of debilitating side effects from medications.
5.     Tens of thousands of deaths occur annually in patients with epilepsy in the United States.
6.     Seizures may cause damage to the brain. In a child's developing brain this often leads to learning disabilities and/or mental retardation.
7.     Epilepsy is an increasing problem for the elderly, developing as a result of stroke, brain tumors and Alzheimers.
8.     In over 50% of patients with epilepsy, the cause is still unknown.
There is no cure for epilepsy


ARTICLES: Epilepsy: an autoimmune disease?
Journal of Neurology, Neurosurgery & Psychiatry 2000; 69:711-714                                                                 February 12, 2006


Epilepsy may present as a symptom of many neurological disorders and often an aetiological explanation cannot be identified. There is growing evidence that autoimmune mechanisms might have a role in some patients. This includes numerous reports of the detection of theoretically relevant serum autoantibodies, experimental data showing that antibodies can be epileptogenic, and a response of some epilepsy syndromes to immunomodulation.
The evidence for immunological mechanisms in epilepsy can be examined within the following three main areas: the childhood epilepsy syndromes, epilepsy associated with other immunologically mediated diseases, and the more common unselected groups of patients with epilepsy.


EXCERPTS from the article:
West's Syndrome (Infantile Spasms) and Lennox-Gastaut syndrome Although both West's syndrome and Lennox-Gastaut syndrome have very different clinical phenotypes, both syndromes have been reported to respond well to IVIg therapy.  Among the numerous unblinded studies published most have reported a positive response to treatment. Van Engelen et al have reviewed the use of IVIg treatment in childhood epilepsies and concluded that although there was no formal evidence of efficacy due to lack of controlled trials, some patients benefited greatly from this treatment.  In one series of children with West's syndrome 33% showed a positive response, with a rapid and permanent resolution in 21% of those treated.11 One placebo controlled (single blind crossover) study of 10 patients with Lennox-Gastaut syndrome reported a reduction in seizures in 20% of patients.
Reports of an activated but functionally impaired immune system, increased serum immunoglobulins and a HLA DR5 association in Lennox-Gastaut syndrome further supports immunological involvement.
Conclusions It seems likely that serum autoantibodies may be associated with some forms of epilepsy. However, epilepsy itself and antiepileptic drugs are reported to alter immune responses and it is not clear which autoantibodies arise as a consequence and which are causative. Furthermore the mechanisms of action of the putative pathogenic antibodies are not well understood.
Immunotherapies seem to have efficacy above standard antiepileptic treatment in some groups of patients. The studies of immunotherapy to date have involved few patients, almost invariably in open labelled designs, mainly due to the rarity of the epilepsy syndromes. Clearly larger placebo controlled trials are needed. Corticosteroid responsiveness does not necessarily indicate immune mediated pathology but could result from a direct inhibitory action on GABA receptors by such treatment.  Conversely, irreparable CNS damage resulting from autoimmune mechanisms could result in a lack of response to immunomodulation. Thus predicting the underlying pathogenesis from the response to treatment can be misleading.

Mechanisms of Seizure-Induced Damage
The reasons that seizures during development can be harmful are myriad. The developing brain is highly plastic, and seizures during early development could have pronounced effects on brain development, perturbing a wide-range of phenomena that is activity-dependent, including cell division, migration, sequential expression of receptors, formation and strengthening of synapses, and myelination. Much of the early work in seizure-induced brain damage has concentrated on cell death. Only recently has it been demonstrated that seizures can alter brain development through mechanisms other than necrosis and programmed cell death.
Source: Epilepsy and Developmental Disabilities, Orrin Devinsky et al.

Epilepsy Cuts Brain Cell Production in Critical Learning, Memory Center
A new study shows that chronic seizures actually decrease new neuron production in the brain's learning and memory center. The study is the first to demonstrate how new neuron production in the brain's "hippocampus" is affected by chronic, rather than acute, seizures, said the researchers from Duke University Medical Center and the Durham VA Medical Center. The hippocampus is the brain region where learning, memory and mood are regulated and where epilepsy causes injury.


In the study, rats with chronic epilepsy showed a 75 percent decrease in new neuron production in the hippocampus compared to normal animals, said Ashok K. Shetty, Ph.D., a research professor of neurosurgery at Duke and the study's senior author. The finding explains why chronic epileptics are prone to learning and memory deficits and depression, he said. Epilepsy occurs when electrical signals in the brain are disrupted, causing uncontrolled body movements and changes in learning, memory and emotion.


Shetty said their new knowledge of neuron growth, or neurogenesis, in chronic epilepsy could lead to treatments that alleviate the learning and memory deficits and mood symptoms that accompany the disease. The findings could potentially even reduce the prevalence of seizures, he said. Results of their study on neurogenesis in rats with epileptic seizures are published in the December issue of Neurobiology of Disease. Bharathi Hattiangady, Ph.D., research associate in neurosurgery, is the lead author, and research associate Muddanna Rao, Ph.D., is co-author of the study. The study is funded the National Institute of Neurological Disorders and Stroke (NINDS) of the National Institutes of Health.


"In the future, we could theoretically treat chronically epileptic patients with stem cell factors that induce new neuron production and see if it alleviates their learning and memory problems and depression; or we could prescribe exercise, enriched environment or anti-depressants," said Shetty. "All of these treatments are known to considerably increase adult neurogenesis in the hippocampus where learning, memory and mood are regulated."


In the Duke study, rats were induced to have seizures and hippocampal injury analogous to humans with temporal lobe epilepsy – the most common form of epilepsy. Immediately following the acute seizures, there was a 60 percent increase in new neuron production in the brain's hippocampus. A respite period with no seizures lasted for four to six weeks, and then seizures recurred with increasing severity – the chronic phase of temporal lobe epilepsy. During the chronic phase, rats displayed an average 75 percent decrease in neurogenesis compared with normal rats. The more frequent the rats' seizures were, the fewer new neurons they produced in the long term, the study showed. And, the fewer neurons their brains produced, the more likely they were to suffer more seizures.
"With chronic epilepsy, the brain's wiring is reorganized to become more excitable," said Shetty. "The seizures induce changes in nerve cells that make them more susceptible to additional seizures." The rapid production of new nerve cells following acute seizures was thought to repair damage, said Shetty. But the Duke study, as well as earlier studies, indicate that such rapid neurogenesis actually dispatches neurons to the wrong places and contributes to abnormal brain circuitry and hyper-excitability of neurons. Moreover, the delicate balance between excitatory neurons that fire signals and inhibitory neurons which halt them is lost, tipping the balance toward hyper-excitability.
"Studying early time-points in the epileptic brain produces an entirely different picture than studying the long-term effects of chronic seizures," said Shetty. "Understanding the brain's long-term response to epileptic injury will enhance our ability to treat the disease," he added.


From Duke University