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To date, most studies in the elderly have not used a syndromic classification. Epileptic
syndromes that occur commonly in the elderly are:
 Remote symptomatic seizures, usually due to precedent stroke or cerebro-vascular

disease. Seizures are usually easy to control.
 Acute symptomatic or provoked seizures, possibly due to acute stroke, toxic or

metabolic causes or secondary to syncope or cerebral systemic infection. Some people
have repeated intercurrent seizures, each related to a recurrent acute situation (e.g.
alcohol or hypoglycaemia).
 Progressive symptomatic seizures, usually caused by a tumour or non-vascular dementia
(though the latter is controversial).
 Cryptogenic cases in which a cause cannot be identified but which are presumed to be
symptomatic. Many such cases are believed to be due to occult cerebro-vascular disease.
 Late onset idiopathic generalised seizures are relatively rare in the elderly; the seizures
are usually easy to control. People may be misdiagnosed as having non-lesional partial
epilepsy. Sleep deprivation EEG studies are indicated.

Diagnostic pitfalls

As in younger people, the diagnosis of epilepsy in the elderly is entirely clinical. Eyewitness
accounts are often lacking and differentiating hypoglycaemia, syncope or impairment of
cerebral circulation from other causes may be difficult. Persistent headache or confusion after
an episode of loss of consciousness is suggestive of a seizure. Recurrent partial seizures are
often misdiagnosed as transient cerebral ischaemia if the stereotypical nature of the epileptic
symptoms is not recognised.

Concurrent disorders that predispose to syncope, e.g. carotid sinus syncope, micturition
syncope, and postural hypotension, are common in the elderly. Focal jerking of one arm may
occur in tight carotid stenosis. The elderly brain may be more sensitive to a number of
external insults. Cardiac arrhythmias frequently present with seizures in the elderly.
Conversely seizures of temporal lobe origin may present with autonomic disturbance and
cardiac dysrhythmia. Even after intensive investigation with EEG and 24-hour ECG,
diagnostic uncertainty may persist in a considerable proportion of people.

Post-ictal states in the elderly may be prolonged; Todd’s paresis may persist for days and is
often misinterpreted as a new stroke. Post-ictal confusion with disorientation, hyperactivity,
wandering and incontinence may persist for up to one week.

Diagnostic difficulties may also arise with neuropsychiatric presentations, e.g. epilepsia
partialis continua may be confused with an involuntary movement disorder, and the rare
paroxysmal sensory epilepsy is often labelled as recurrent transient cerebral ischaemia.

Prognosis in elderly with seizures and epilepsy

The National General Practice Study of Epilepsy7 reported an 80% risk of seizure recurrence
in older people at 52 weeks. Remote symptomatic seizures carried a higher risk of recurrence
(85%) at three years than acute symptomatic seizures (46%). Other studies have not found
older age to be a significant predictor of recurrence10,11. The presence of Todd’s paresis or
previous acute symptomatic seizures relating to the original insult appears to increase the risk
of recurrence11. A classic study examined prognosis in a large group of elderly admitted to
hospital following a seizure12. Of those not previously treated and observed for at least 12
months, 62% remained seizure free and 26% had less than three seizures per year; 72% of
the whole group entered remission within the first year. No controlled clinical trials exist but