Epilepsy in the elderly: prognosis

Prognosis of adults and children following a first unprovoked seizure

BACKGROUND

Epilepsy is clinically defined as two or more unprovoked epileptic seizures more than 24 hours apart. Given that, a diagnosis of epilepsy can be associated with significant morbidity and mortality, it is imperative that clinicians (and people with seizures and their relatives) have access to accurate and reliable prognostic estimates, to guide clinical practice on the risks of developing further unprovoked seizures (and by definition, a diagnosis of epilepsy) following single unprovoked epileptic seizure.

OBJECTIVES

1. To provide an accurate estimate of the proportion of individuals going on to have further unprovoked seizures at subsequent time points following a single unprovoked epileptic seizure (or cluster of epileptic seizures within a 24-hour period, or a first episode of status epilepticus), of any seizure type (overall prognosis). 2. To evaluate the mortality rate following a first unprovoked epileptic seizure.

SEARCH METHODS

We searched the following databases on 19 September 2019 and again on 30 March 2021, with no language restrictions. The Cochrane Register of Studies (CRS Web), MEDLINE Ovid (1946 to March 29, 2021), SCOPUS (1823 onwards), ClinicalTrials.gov, the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). CRS Web includes randomized or quasi-randomized, controlled trials from PubMed, Embase, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP), the Cochrane Central Register of Controlled Trials (CENTRAL), and the Specialized Registers of Cochrane Review Groups including Epilepsy. In MEDLINE (Ovid) the coverage end date always lags a few days behind the search date.

SELECTION CRITERIA

We included studies, both retrospective and prospective, of all age groups (except those in the neonatal period (< 1 month of age)), of people with a single unprovoked seizure, followed up for a minimum of six months, with no upper limit of follow-up, with the study end point being seizure recurrence, death, or loss to follow-up. To be included, studies must have included at least 30 participants. We excluded studies that involved people with seizures that occur as a result of an acute precipitant or provoking factor, or in close temporal proximity to an acute neurological insult, since these are not considered epileptic in aetiology (acute symptomatic seizures). We also excluded people with situational seizures, such as febrile convulsions.

DATA COLLECTION AND ANALYSIS

Two review authors conducted the initial screening of titles and abstracts identified through the electronic searches, and removed non-relevant articles. We obtained the full-text articles of all remaining potentially relevant studies, or those whose relevance could not be determined from the abstract alone and two authors independently assessed for eligibility. All disagreements were resolved through discussion with no need to defer to a third review author. We extracted data from included studies using a data extraction form based on the checklist for critical appraisal and data extraction for systematicreviews of prediction modelling studies (CHARMS). Two review authors then appraised the included studies, using a standardised approach based on the quality in prognostic studies (QUIPS) tool, which was adapted for overall prognosis (seizure recurrence). We conducted a meta-analysis using Review Manager 2014, with a random-effects generic inverse variance meta-analysis model, which accounted for any between-study heterogeneity in the prognostic effect. We then summarised the meta-analysis by the pooled estimate (the average prognostic factor effect), its 95% confidence interval (CI), the estimates of I² and Tau² (heterogeneity), and a 95% prediction interval for the prognostic effect in a single population at three various time points, 6 months, 12 months and 24 months. Subgroup analysis was performed according to the ages of the cohorts included; studies involving all ages, studies that recruited adult only and those that were purely paediatric.

MAIN RESULTS

Fifty-eight studies (involving 54 cohorts), with a total of 12,160 participants (median 147, range 31 to 1443), met the inclusion criteria for the review. Of the 58 studies, 26 studies were paediatric studies, 16 were adult and the remaining 16 studies were a combination of paediatric and adult populations. Most included studies had a cohort study design with two case-control studies and one nested case-control study. Thirty-two studies (29 cohorts) reported a prospective longitudinal design whilst 15 studies had a retrospective design whilst the remaining studies were randomised controlled trials. Nine of the studies included presented mortality data following a first unprovoked seizure. For a mortality study to be included, a proportional mortality ratio (PMR) or a standardised mortality ratio (SMR) had to be given at a specific time point following a first unprovoked seizure. To be included in the meta-analysis a study had to present clear seizure recurrence data at 6 months, 12 months or 24 months. Forty-six studies were included in the meta-analysis, of which 23 were paediatric, 13 were adult, and 10 were a combination of paediatric and adult populations. A meta-analysis was performed at three time points; six months, one year and two years for all ages combined, paediatric and adult studies, respectively. We found an estimated overall seizure recurrence of all included studies at six months of 27% (95% CI 24% to 31%), 36% (95% CI 33% to 40%) at one year and 43% (95% CI 37% to 44%) at two years, with slightly lower estimates for adult subgroup analysis and slightly higher estimates for paediatric subgroup analysis. It was not possible to provide a summary estimate of the risk of seizure recurrence beyond these time points as most of the included studies were of short follow-up and too few studies presented recurrence rates at a single time point beyond two years. The evidence presented was found to be of moderate certainty.

AUTHORS' CONCLUSIONS

Despite the limitations of the data (moderate-certainty of evidence), mainly relating to clinical and methodological heterogeneity we have provided summary estimates for the likely risk of seizure recurrence at six months, one year and two years for both children and adults. This provides information that is likely to be useful for the clinician counselling patients (or their parents) on the probable risk of further seizures in the short-term whilst acknowledging the paucity of long-term recurrence data, particularly beyond 10 years.

Frequency and Stratification of Epileptogenic Lesions in Elderly With New Onset Seizures

Objective: To evaluate prospectively the frequency of epileptogenic lesions in a consecutive cohort of elderly patients presenting with new onset unprovoked seizures, and who underwent a complete evaluation including dedicated epilepsy protocol MRI.

Methods and materials: We included all consecutive patients 60 years or older who participated in a prospective study on new onset epilepsy. The work-up included the acquisition of a dedicated epilepsy protocol MRI and a 3 h video/EEG recording. We evaluated the frequency and types of epileptogenic lesions in the whole cohort and stratified those variables by age, gender, types and number of seizures at presentation. We also correlated the EEG findings with the clinical characteristics and neuroimaging results.

Results: Of the 101 patients enrolled in the study and who underwent an epilepsy protocol MRI, an epileptogenic lesion was identified in 67% of cases. The most common etiologies were vascular events, followed by tumoral causes and traumatic brain injuries. Epileptogenic lesions were more likely to be identified in patients who presented with only focal aware and impaired awareness seizures. In addition, patients with tumoral epilepsy were significantly more likely to only experience those seizure types compared to patients with other pathological substrates. Interictal/ictal discharges were detected in the EEG of 21% of patients. Epileptiform discharges were significantly more frequent in patients with an epileptogenic lesion on brain MRI, especially in those with a brain tumor.

Conclusions: Our results stress the importance of obtaining a dedicated epilepsy protocol MRI in elderly patients with new onset seizures. An epileptogenic lesion will be identified in approximately two thirds of patients with important implications regarding initiation of treatment. In addition, the data underscore the value of distinguishing the types of seizures experienced at presentation as this will apprise the treating physician on the likelihood of identifying an epileptogenic lesion and on the probable etiologies.

Epilepsy and dementia in the elderly

Epilepsy is a frequent condition in the elderly; however, it remains a relatively understudied condition in older adults with dementia. The diagnosis of a seizure is particularly difficult and is most often based on questions to the caregiver. Epilepsy in dementia has significant consequences on the prognosis of the underlying dementia: it can result in a worsening of cognitive performance, particularly in language, as well as a reduction in autonomy, a greater risk of injury and a higher mortality rate. In this review, management strategies are recommended for the clinician. The presence of pre-existing Alzheimer's disease does not exempt the clinician from ruling out other symptomatic causes of seizures. Anti-epileptic drugs (AED) should be started only after the diagnosis has been clearly established, when the risk of recurrence is high, and with monotherapy whenever possible. Although few data are available, the more recent AED offer significant advantages over the older medications in this context.

Medical decision-making abilities in older adults with chronic partial epilepsy

Little is known about the medical decision-making abilities of older adults with chronic partial epilepsy, although these patients are often faced with medical decisions that impact their health care. Twenty-one older adults with epilepsy and 21 healthy older adults completed the Capacity to Consent to Treatment Instrument (CCTI) and Dementia Rating Scale II (DRS-II). Older adults with epilepsy performed significantly below controls on the CCTI standards Evidencing Choice, Appreciation, and Understanding and the DRS-II Total Score. DRS-II was positively associated with performance on the standards Appreciation and Understanding. Number of antiepileptic drugs, duration of epilepsy, and age at seizure onset were related to performance on Understanding. Older adults with epilepsy demonstrated deficits in their capacity to give informed consent for medical treatment that appear to be associated with cognition and seizure variables. Physicians should consider the decisional abilities of their older adult patients with epilepsy when presenting treatment options.

Older adults with epilepsy demonstrate cognitive impairments compared with patients with amnestic mild cognitive impairment

Little is known about the cognitive effects of chronic epilepsy in older adults. To better characterize cognitive impairment in seniors with epilepsy, we compared cognitive performance of 26 seniors with epilepsy with that of 26 well-matched patients with mild cognitive impairment (MCI) and 26 well-matched healthy older adults. Participants completed neuropsychological testing with the Dementia Rating Scale (DRS), Logical Memory, and CFL Word Fluency. There were no significant demographic group differences, although seniors with epilepsy had higher self-reported depression. Seniors with epilepsy performed below controls on virtually all neuropsychological tests, and performed below patients with MCI on DRS Total score, Initiation/Perseveration, and CFL Fluency. Seniors with epilepsy on antiepileptic drug (AED) polytherapy had the most severe cognitive deficits, whereas seniors with epilepsy on AED monotherapy were comparable to cholinesterase inhibitor-naïve patients with MCI. This study emphasizes the clinical importance of cognitive impairment in seniors with epilepsy and highlights the need for future studies addressing causes and treatment of cognitive impairment.

Cognitive functioning in community dwelling older adults with chronic partial epilepsy

PURPOSE

To examine cognitive functioning in community-dwelling older adults with chronic partial epilepsy and demographically matched healthy older adults.

METHODS

Standardized measures of neurocognitive function were collected as part of an ongoing study investigating health-related quality-of-life issues in older adults with epilepsy. Cognitive tests consisted of the Mattis Dementia Rating Scale (subscales include attention, initiation/perseveration, construction, conceptualization, memory), Logical Memory subtest from the WMS-III (immediate and delayed recall scores), and word fluency. Mood was measured with the Geriatric Depression Scale. Older adults with epilepsy (n=25) and healthy older adults (n=27) completed testing. All participants were at least 60 years old, living independently in the community, and had no history of drug/alcohol abuse or life-threatening medical conditions. All older adults with epilepsy had been diagnosed as having medically intractable partial complex seizures, including those with histories of secondary generalization.

RESULTS

Older adults with epilepsy demonstrated impairments across all cognitive measures compared with the healthy controls. Seizure onset (age) and seizure duration (years) were not statistically associated with neurocognitive function or self-reported mood. Older adults with epilepsy who were receiving antiepileptic drug (AED) polytherapy (n=11) displayed worse performance on the attention, initiation/perseveration, and memory subscales of the DRS and Logical Memory delayed recall score compared with those older adults with epilepsy receiving monotherapy (n=14). The number of AEDs taken was not associated with seizure frequency.

CONCLUSIONS

Negative effects on cognitive function are experienced by older adults with chronic partial epilepsy. AED polytherapy may increase the risk for negative cognitive dysfunction.

Seizure Semiology in the Elderly: A Video Analysis

PURPOSE

To describe the seizure semiology of patients older than 60 years and to compare it with that of a control group of younger adults matched according to the epilepsy diagnosis.

METHODS

Available videotapes of all patients aged 60 years and older who underwent long-term video-EEG evaluation at the Cleveland Clinic Foundation (CCF) between January 1994 and March 2002 were analyzed by two observers blinded to the clinical data. A younger adult control group was matched according to the epilepsy diagnosis, and their seizures also were analyzed.

RESULTS

Fifty-four (3.3%) of the 1,633 patients were 60 years or older at the time of admission. For 21 of them, at least one epileptic seizure was recorded. Nineteen patients had focal epilepsy (nine temporal lobe, two frontal lobe, two parietal lobe, eight nonlocalized), and two patients had generalized epilepsy. Seventy-three seizures of the elderly patients and 85 seizures of the 21 control patients were analyzed. In nine elderly patients and 14 control patients, at least one of their seizures started with an aura. Eleven elderly patients and 19 control patients lost responsiveness during their seizures. Approximately two thirds of the patients in both groups had automatisms during the seizures. Both focal and generalized motor seizures (e.g., clonic or tonic seizures) were seen less frequently in the elderly.

CONCLUSIONS

Only a small percentage of the patients admitted to a tertiary epilepsy referral center for long-term video-EEG monitoring are older than 60 years. All seizure types observed in the elderly also were seen in the younger control group, and vice versa. Simple motor seizures were seen less frequently in the elderly.

Seizures in elderly patients with dementia: epidemiology and management

Epileptic seizures occur in patients with dementia at a higher prevalence than among healthy elderly individuals. The incidence of seizures among patients with dementia varies with the aetiology of the dementing illness. In patients with Alzheimer's disease (the most common form of dementia), approximately 10-22% have at least one unprovoked seizure. Seizures usually occur in later stages of Alzheimer's disease, on average, > or =6 years into the course of the disease. Seizures in Alzheimer's disease are more likely to occur with early-onset disease, particularly if there is a familial presenilin I mutation. The incidence of seizures in other dementing diseases is less clear. There are special considerations regarding the management of seizures in the elderly with dementia. First, the presence of cognitive impairment may impede an accurate diagnosis of seizures. Clinicians may also mistake seizure manifestations for symptoms of the underlying dementia. Second, since most dementia patients are elderly, there are pharmacokinetic changes with aging that affect the use of antiepileptic drugs. Third, antiepileptic drugs have potential cognitive adverse effects that may worsen dementia. Although few studies are available, extrapolations from research in young people and elderly patients without dementia provide several recommendations for the management of seizures in patients with dementia: exclude symptomatic causes of seizures before committing to antiepileptic drug therapy; treat after a first seizure if there is evidence of focal neurological involvement or a risk of recurrent seizures; use antiepileptic drugs with minimal cognitive adverse effects, such as carbamazepine, valproic acid, gabapentin and lamotrigine; and use the lowest possible dosage and monitor antiepileptic drug levels, where possible.

Strategies for optimizing antiepileptic drug therapy in elderly people

The elderly take more antiepileptic drugs (AEDs) than all other adults. This extensive use directly correlates with an increased prevalence of epilepsy in a growing population of older people, as well as other neuropsychiatric conditions such as neuropathic pain and behavioral disorders associated with dementia and for which AEDs are administered. The agents account for nearly 10% of all adverse drug reactions in the elderly and are the fourth leading cause of adverse drug reactions in nursing home residents. Numerous factors associated with advanced age contribute to the high frequency of untoward drug effects in this population; however, strategies are available to ensure optimal outcomes.

Treating epilepsy in the elderly: safety considerations

The incidence of epilepsy increases with advancing age. Epilepsy in the elderly has different aetiologies from that in younger populations, cerebrovascular disease being the most common condition associated with seizures. Partial seizures are the predominant seizure type in older patients. A diagnosis of epilepsy in the elderly is based mainly on the history and is frequently delayed. In addition, seizure imitators are especially frequent. In many cases ancillary tests for diagnosis may show normal age-related variants, sometimes making results difficult to interpret. Treating epilepsy in the elderly is problematic due to a number of issues that relate to age and comorbidity. The physical changes associated with increasing age frequently lead to changes in the pharmacokinetics of many anticonvulsants. The treatment of epilepsy in the elderly is also complicated by the existence of other diseases that might affect the metabolism or excretion of anticonvulsants and the presence of concomitant medications that might interact with them. Moreover, specific trials of anticonvulsants in the aged population are scarce. General guidelines for treatment include starting at lower doses, slowing the titration schedule, individualising the choice of anticonvulsant to the characteristics of the patient, avoiding anticonvulsants with important cognitive or sedative adverse effects, and where possible, treating with monotherapy.

Clinical-neurophysiological features of motor lesions in patients with post-stroke epilepsy

Twenty-two patients with post-stroke epilepsy (group 1) were studied, along with 30 stroke patients without epilepsy (group 2). Bilateral (on both the paralyzed and intact sides) decreases in the central conduction time (CCT) along the pyramidal tract were found in group 1, which were not seen in group 2, who had similarly severe motor lesions (p < 0.01). The tendency to decreased CCT was also seen 5-6 days after ischemic stroke in patients without epileptic manifestations, though CCT in this group increased by day 10-14; low values persisted in group 1 for prolonged periods. The facilitation differentiation (deltaF, the difference in CCT between resting and effort conditions) was also found to increase. In patients with post-stroke epilepsy, motor lesions were characterized by higher levels of muscle tone than in other stroke patients, though the levels of paralysis were similar.

First ever seizures in the elderly: a seven-year follow-up study

The clinical characteristics and prognosis of first ever seizures among the elderly (aged 65 years or more) were ascertained by following up a cohort of patients for 7 years. Twenty-three patients (mean age, 69.9 +/- 4.9 years) were registered in the Neurology Service between January 1988 and March 1989. Twelve patients had partial seizures with or without generalization. Three patients had status epilepticus, whereas ten had presented for single seizure. On presentation 61.9% patients had neurological deficits and 73.9% had one or more systemic disorder. Head computerized tomography scans were abnormal in 17 cases. Seizures were attributed to acute stroke (26.1%), trauma (8.7%), subdural haematoma, degenerative diseases of the brain, cerebral metastasis, or central nervous system infections. The cause was unknown in 43.5% cases. At the end of 7 years, follow-up was complete for 15 patients (65.2%). The mean duration of follow-up was 68.6 +/- 28.7 months. Eight (53.3%) patients had died. Nine patients (60%) had attained 2-year remission of which three remained seizure free throughout. Six of the seven living patients were continuing antiepileptic drugs treatment. Forty per cent of them were dependent on others for the activities of daily life.

Management of Seizures in the Elderly: A Survey of UK Geriatricians

The incidence and prevalence of epilepsy increase substantially with old age. Despite this, the investigation and management of this patient population remains a grey area. Four hundred and eleven (53%) consultant geriatricians responded to a questionnaire exploring their approach to seizures in the elderly in order to establish an overview of current clinical practice. Between one and five patients presenting with seizures, predominantly aged between 75–85 years, were reviewed monthly. Seventy per cent of geriatricians undertook to investigate the patients themselves with biochemical and haematological profiles performed by most. Electroencephalography and computerized tomographic scanning were routinely requested by a quarter of responders. Only 58% would themselves initiate therapy with antiepileptic drugs, with 16% of consultants starting treatment following the first seizure, 59% after a second and 5% after a third. Phenytoin was first choice for generalized tonic-clonic seizures with carbamazepine preferred for partial seizures. If good control was not obtained, 67% would substitute another first line drug, while 27% would add in a second. Less than 3% would use the new anticonvulsants lamotrigine or vigabatrin. Sixty per cent monitored anticonvulsant concentrations in patients with poor control or suspected toxicity. A wide variability was seen in the current approach to seizures in the elderly, which reflects a lack of established practice. Epilepsy clinics for the elderly would encourage structured research into the many unanswered questions affecting the care of older people with seizures.

Anticonvulsant therapy in the elderly--a need for placebo controlled trials

Epileptic seizures are common in the elderly, yet data concerning the long-term clinical course and apparent impact of anticonvulsant therapy are scant. We studied 73 consecutive elderly patients with a diagnosis of seizures [remote symptomatic (52%), acute symptomatic (23%), progressive symptomatic (10%), cryptogenic (15%)] during a median period of clinical review of 33 (range 3-72) months. Sixty-seven patients received anticonvulsant drugs, 38 phenytoin (PHT), 21 carbamazepine (CBZ), 6 sodium valproate (VPA) and 2 phenobarbitone. Six patients were untreated with drugs and three of these had no further seizures over a median review period of 26 months. Forty-one (61%) treated patients remained seizure free and a further nine patients suffered less than three fits per year. Seventeen patients had poorer control (three to five seizures per year in six patients and more than five seizures per year in eleven patients). Mean daily dosage of anticonvulsants (PHT 248 mg, CBZ 320 mg, VPA 571 mg) and serum concentrations were modest. Anticonvulsant side effects were reported by 27% of all treated patients (22% of those who were seizure free). Both adverse effects and satisfactory seizure control were associated in the majority of patients with serum anticonvulsant concentrations at the lower limit or below recommended therapeutic ranges utilised in the young. This study suggests that placebo controlled studies are warranted to appraise the extent to which anticonvulsant drugs modify a generally favourable prognosis for seizure disorders in the elderly and to adequately define the benefit-risk ratio of such drugs.

Risk of recurrence after first unprovoked tonic-clonic seizure in adults

The likelihood of seizure recurrence after a first unprovoked seizure has profound social, vocational and emotional implications for the patients. Recurrence rates have varied between 27% and 71% in various studies, and the management of patients with a single unprovoked seizure is a controversial topic. In this prospective study we investigated the influence of age, sex, family history, EEG patterns, and anticonvulsant drug (ACD) therapy on seizure recurrence after a first unprovoked tonic-clonic seizure in adults. For this purpose, between October 1988 and January 1991, we studied adult patients who had experienced their after unprovoked tonic-clonic seizure within last 2 months before neurological consultation, and followed them until June 1993. There were 147 patients who met the criteria for inclusion. Overall cumulative recurrence rates were 31.8% by 6 months, 41.3% by 1 year, 44.1% by 2 years, 42.2% by 3 years, and 45.2% by 4 years. Among the risk factors that were evaluated, the time of the day at which the initial seizure occurred was associated significantly (P < 0.05) with seizure recurrence. In our series, 62 patients received ACD and 85 did not. We did not find a significant difference in recurrence rate with regard to ACD therapy. Our results are comparable with those of studies reported previously and suggest that the majority of recurrences after a first unprovoked seizure were seen in the first year (in our series 89% of all recurrences). In our study there was no significant predictor of seizure recurrence, except the time of day at which the initial seizure occurred.

Magnetic resonance imaging and late-onset epilepsy

The value of magnetic resonance imaging (MRI) in investigation of patients with late-onset epilepsy has not been studied systematically. We evaluated prospectively the usefulness of MRI in 50 patients with late-onset epilepsy in whom a computed tomography (CT) scan was normal (32), did not allow a definitive diagnosis to be made (12), or showed irrelevant lesions (6). Patients were assessed clinically and had an EEG, and CT and MRI scans were reported by one neuroradiologist blinded to clinical and laboratory data. Of the 32 patients with a normal CT scan, MRI was normal in 20, showed irrelevant ischemic lesions in 8, and showed the cause of seizures in 4 patients. Of the 12 patients with nondiagnostic CT, MRI clarified the diagnosis in 5 and was normal in 2 patients. In 6 patients, both scans showed irrelevant ischemic lesions, and in 1 patient MRI showed a relevant additional lesion. The incidence of MRI-detected white matter ischemic lesions was no greater than in an age- and sex-matched group of subjects without seizures. MRI was diagnostic in 32% of the patients with partial seizures and/or focal EEG findings, as compared with 0% of patients without focal features (p less than 0.01). We conclude that MRI is useful in investigation of patients with late-onset epilepsy with focal features.

Idiopathic first seizure in adult life: who should be treated?

OBJECTIVE

To assess the accuracy of the diagnosis, recurrence rate, and fate after the first recurrence in adult patients with an untreated idiopathic first seizure.

DESIGN

Hospital based follow up study.

SETTING

One university hospital and three general hospitals in The Netherlands.

PATIENTS

165 patients aged 15 years or more with a clinically presumed idiopathic seizure; diagnosis was based on a description of the episode according to prespecified diagnostic criteria.

MAIN OUTCOME MEASURES

Results of additional investigations and follow up regarding the accuracy of the diagnosis; first recurrence; and response to treatment after the first recurrence.

RESULTS

Computed tomography showed major abnormalities in 5.5% of the patients and follow up led to doubts about the initial clinical diagnosis in another 6%. Cumulative risk of recurrence was 40% at two years. The cumulative risk of recurrence at two years was 81% (95% confidence interval 66% to 97%) in patients with epileptic discharges on a standard or partial sleep deprivation electroencephalogram, 39% (27% to 51%) in patients with other electroencephalographic abnormalities, and 12% (3% to 21%) in patients with normal electroencephalograms. Treatment was initiated in most patients who had one or more recurrences; 40 (70%) patients were completely controlled, eight (14%) had sporadic seizures, and nine (16%) did not become free of seizures within one year despite treatment.

CONCLUSIONS

The decision to initiate or delay treatment should be based on electroencephalographic findings.

Epileptic seizures and cerebrovascular disease

A series of 88 patients with completed stroke was selected in which heralding, early and late seizures were distinguished according to their onset. Relationships between CT scan and clinical EEG data are discussed with particular emphasis on possible mechanisms of seizures. Thus, small emboli or haemodynamic factors are stressed in the cases of heralding seizures, metabolic disturbances with cytotoxic effects in early seizures and chronic epileptic focus in late seizures.

Epilepsy in the elderly: life expectancy and causes of death

All patients over the age of 60 who experienced seizures between 1979-83, were registered. The number of deaths was registered until July 2, 1985. Included were 162 patients who received no anti-epileptic drugs prior to the study period; 87 patients had established epilepsy at the time of admission. The number of deaths among previously untreated patients significantly exceeded expectation. Mortality was not significantly correlated to severity of epilepsy. In patients with brain tumor all but one died within the first year. Mortality among patients with postapoplectic seizures was significantly higher than expected being especially during the first year. Numbers of deaths among patients with seizures of unknown cause did not differ from the expected, neither did causes of death. Numbers of deaths in patients with established epilepsy at the time of admission was significantly higher than expected although none had malignant tumours and only 4 had postapoplectic seizures thus illustrating the influence of selecting patients with chronic active epilepsy. Eleven patients died suddenly and unexpectedly of unknown cause, which was more than expected. These patients were found dead under circumstances compatible with death occurring during seizure. Epilepsy was mentioned on the death certificate in only one case, indicating that the frequency of sudden, unexpected death among epileptics could easily be underestimated.