Incidence and mortality

Both the incidence and complications of status epilepticus increase with aging. Morbidity and mortality increase steadily with age after age 20, mortality rates being in excess of 50% in patients over age 80.84,85 To some extent this statistic both reflects and interacts with other mortality risk factors, including duration of status and, especially, etiology. (See more information on Complications and Prognosis.)

Causes

The highest mortality rates occur when status epilepticus is associated with anoxia, infection, metabolic dysfunction, trauma, tumor, and vascular disease, particularly hemorrhage.85

Status epilepticus brought on by the abrupt discontinuation of AED therapy, a major precipitant among patients with known epilepsy, continues to have a relatively good prognosis in older patients, if treated promptly.

Treatment

Prompt treatment is especially important in seniors, to avoid systemic complications86,87 such as:

  • blood pressure lability
  • hypoxemia
  • acidosis
  • rhabdomyolysis with renal failure

Seniors are more sensitive than younger people to the hypotensive and respiratory suppressant effects of intravenously administered AEDs, particularly phenytoin, barbiturates, and benzodiazepines. Vital signs must be carefully monitored and sometimes the rate of infusion must be slowed, despite the risk of prolonging status. Phenytoin, for example, should probably be infused at rates no greater than 25 mg/min.

An interesting alternative for second-line treatment is intravenous valproate, which, though not currently FDA-approved for the treatment of status epilepticus, can be safely loaded at a rapid rate without significant cardiorespiratory suppression. 94

The decision to use pentobarbital coma in refractory status is particularly difficult. Increased complications related to age beyond 40 and to multiple organ failure have been documented.88

Data are insufficient to determine whether midazolam infusion is safer. Anecdotal reports suggest that it may be.89 Propofol is another option for refractory status epilepticus. Retrospective studies do not conclusively distinguish among these three alternatives with respect to efficacy and safety.95

Other neurologic or medical conditions may mimic nonconvulsive generalized90,91 or partial92,93 status epilepticus. A thorough history, examination, and testing may prevent iatrogenic harm from inappropriate treatment.

Adapted from: Bromfield EB. Epilepsy and the elderly. In: Schachter SC, Schomer DL, eds. The comprehensive evaluation and treatment of epilepsy. San Diego, CA: Academic Press; 1997. p. 233-254.
With permission from Elsevier (www.elsevier.com).

Authored By: 
Edward Bromfield MD
Steven C. Schachter MD
Donald L. Schomer MD
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