Annals of Long Term Care

Introduction
Although many consider epilepsy a condition of childhood, the highest incidence of new-onset epilepsy occurs in individuals over the age of 60 (Figure 1). Seizures can be either provoked or unprovoked. Metabolic disturbances and alcohol withdrawal are common causes of acute provoked seizures, and treatment is directed towards the underlying provoking medical condition. In contrast, the diagnosis of epilepsy is made when a patient experiences recurrent unprovoked seizures. In this short review, issues surrounding acute provoked seizures in the geriatric population will not be discussed. Instead, we will address: (1) the type of epilepsy older individuals experience, (2) the causes of new-onset epilepsy in the elderly,(3) the diagnostic evaluation of the older patient with spells of alteration in level of consciousness, and (4) the treatment of epilepsy in the elderly. The older antiepileptic drugs (AEDs), especially phenobarbital and phenytoin, have recently fallen out of favor for treatment of the elderly, primarily because of their side-effect profile. Many neurologists advocate the use of the newer AEDs (eg, lamotrigine, gabapentin) since they are effective and better tolerated in the older individual with a seizure disorder.

Types of Seizures
One of the major developments in the field of epilepsy has been the adoption of the International Classification of Epileptic Seizures (ICES), which recognizes two major categories of seizures: those that begin locally in a specific region of the brain and then spread (partial seizures); and those that are widespread with no identifiable focal origin at onset (generalized seizures).1 In contrast to children who commonly present with generalized seizures, the majority of older individuals who develop new-onset epilepsy experience partial seizures. Partial seizures are subdivided based on the impact of the seizure on consciousness. Simple partial seizures are typically brief (less than a minute) and consciousness is preserved, although communication skills may be impaired. During a simple partial seizure, a patient may experience abnormalities of movement (eg, twitching), emotions (eg, fear), or sensations (eg, visual disturbances) that correspond to the affected region of the brain. In the past, the term aura was used to describe the simple partial seizure, or warning, sensed by some patients before the loss of consciousness experienced with spread of the abnormal epileptic discharge in the brain and evolution to a complex partial seizure. During a complex partial seizure, consciousness is altered. Typically, complex partial seizures last 1-3 minutes and involve a larger area of the brain. Often starting with a blank stare, patients can develop nonpurposeful movements (automatisms), such as chewing or fumbling with objects. Confused and frequently still ambulatory, these patients are at risk for falls and injuries. Partial seizures can spread and evolve into generalized tonic clonic seizures (previously called grand mal seizures). Status epilepticus, defined as continuous seizure activity or multiple seizures without a return of consciousness, is almost twice as common in the elderly than in younger adults and is associated with significant morbidity and mortality.2,3

Etiology of Seizures
It is not surprising that partial seizures are the most common type of seizures in the elderly, since stroke is the most commonly identified cause of new-onset epilepsy in the geriatric population. Risk factors for the development of post-stroke epilepsy include hemorrhage, cortical involvement, and a history of acute symptomatic seizures.4 Unfortunately, there is no way of determining which stroke patients will develop epilepsy, and there is no role for prophylactic AED therapy.