Once thought to be the result of demonic or supernatural forces, seizures were regarded with fear by ancient societies and treated with magic or religion. Today, adult-onset seizures are known to be either a symptom of associated disorders, such as alcoholism or Alzheimer's disease, or a primary condition. When multiple unprovoked seizures occur, doctors may diagnose epilepsy. This seizure disorder may be classified as primary or secondary to other conditions affecting the central nervous system.
Types
Seizures in adults may be due to temporary conditions, such as withdrawal from alcohol, the effects of drugs, or stopping medications such as minor tranquilizers. An imbalance of blood components, such as sodium, glucose, calcium or magnesium, can also cause seizures. Illnesses that affect the brain such as dementia, meningitis, encephalitis or AIDS might induce seizures. Other reasons for seizures include brain abscesses or tumors. Traumatic brain injury or stroke may alter the structure and function of brain tissue, triggering seizure activity.
Primary epilepsy may be caused by inherited traits. A family history may also be a factor in idiopathic seizures, or those that have no known cause. Seizures due to fever are rare in adults, according to Sandra Kammerman and Lloyd Wasserman, researchers from the New York University School of Medicine and authors of an article on seizure disorders published in the August 2001 issue of "Western Journal of Medicine."
Prevalence
Kammerman and Wasserman report that stroke is the most common neurological disorder in the United States, followed by Alzheimer's disease and epilepsy, and that the incidence of new-onset epilepsy increases with age. People over age 75 are twice as likely to develop epilepsy as adults under the age of 65.
Medical History
Common causes of seizures in adults are differentiated in large part by their history. Doctors will interview witnesses for a description of how the seizure began, how long it lasted, what body parts were affected, and the type of movements that were observed, such as writhing, stiffness, or shaking. The person's behavior following the seizure might also provide clues, narrowing down possible causes.
Features
Causes of adult seizures fit into two main categories: epileptic and nonepileptic. Nonepileptic causes may be temporary, depending on risk factors and events leading up to the seizures. Differentiating epilepsy as a cause of seizures is dependent on specific features of the disease, such as distinctive sounds. Researchers from the University of South Florida studied audio recordings of 20 epileptic seizures and 20 nonepileptic seizures. A characteristic vocalization called the "ictal cry" was heard in 85 percent of epileptic seizures and was absent in all of the nonepileptic seizures.The findings, published in the July 2010 issue of "Epilepsy and Behavior," suggest that doctors can rely on the ictal cry to diagnose epilepsy as the cause of seizure activity.
Considerations
The cause of seizures may influence economic and social as well as treatment considerations. The likelihood of recurrence of seizures is a concern for obtaining a driver's license in the United States and elsewhere. Proof of having been free of seizures for one year is a common requirement. In addition, persons with epilepsy are protected from housing and workplace discrimination by the Americans With Disabilities Act.
