Epilepsy in the elderly: life expectancy and causes of death

Association of comorbid-socioeconomic clusters with mortality in late onset epilepsy derived through unsupervised machine learning

BACKGROUND AND OBJECTIVES

Late-onset epilepsy is a heterogenous entity associated with specific aetiologies and an elevated risk of premature mortality. Specific multimorbid-socioeconomic profiles and their unique prognostic trajectories have not been described. We sought to determine if specific clusters of late onset epilepsy exist, and whether they have unique hazards of premature mortality.

METHODS

We performed a retrospective observational cohort study linking primary and hospital-based UK electronic health records with vital statistics data (covering years 1998-2019) to identify all cases of incident late onset epilepsy (from people aged ≥65) and 1:10 age, sex, and GP practice-matched controls. We applied hierarchical agglomerative clustering using common aetiologies identified at baseline to define multimorbid-socioeconomic profiles, compare hazards of early mortality, and tabulating causes of death stratified by cluster.

RESULTS

From 1,032,129 people aged ≥65, we identified 1048 cases of late onset epilepsy who were matched to 10,259 controls. Median age at epilepsy diagnosis was 68 (interquartile range: 66-72) and 474 (45%) were female. The hazard of premature mortality related to late-onset epilepsy was higher than matched controls (hazard ratio [HR] 1.73; 95% confidence interval [95%CI] 1.51-1.99). Ten unique phenotypic clusters were identified, defined by 'healthy' males and females, ischaemic stroke, intracerebral haemorrhage (ICH), ICH and alcohol misuse, dementia and anxiety, anxiety, depression in males and females, and brain tumours. Cluster-specific hazards were often similar to that derived for late-onset epilepsy as a whole. Clusters that differed significantly from the base late-onset epilepsy hazard were 'dementia and anxiety' (HR 5.36; 95%CI 3.31-8.68), 'brain tumour' (HR 4.97; 95%CI 2.89-8.56), 'ICH and alcohol misuse' (HR 2.91; 95%CI 1.76-4.81), and 'ischaemic stroke' (HR 2.83; 95%CI 1.83-4.04). These cluster-specific risks were also elevated compared to those derived for tumours, dementia, ischaemic stroke, and ICH in the whole population. Seizure-related cause of death was uncommon and restricted to the ICH, ICH and alcohol misuse, and healthy female clusters.

SIGNIFICANCE

Late-onset epilepsy is an amalgam of unique phenotypic clusters that can be quantitatively defined. Late-onset epilepsy and cluster-specific comorbid profiles have complex effects on premature mortality above and beyond the base rates attributed to epilepsy and cluster-defining comorbidities alone.

New onset epilepsy in the elderly: clinical, radiological and electroencephalographic features and treatment responses

OBJECTIVE

To evaluate new onset epilepsy characteristics, etiology, radiological and electroencephalographic features and to document treatment response in the elderly.

METHODS

This was a retrospective study carried out in King Fahd Medical City, Riyadh, Kingdom of Saudi Arabia, from 2010 to 2013. Medical records were searched to recruit patients. Hundred and nineteen patients were enrolled who fulfill the inclusion criteria. Clinical data with respect to seizure semiology, etiology, electroencephalographic findings, radiological findings, co-morbidities, and anti-epileptic drug (AED) therapy were assessed.

RESULTS

Cerebrovascular disease was the most common etiology, followed by occult cerebrovascular disease (oCVD). Focal onset seizures were the most common clinical presentation in this group of cohort. Electroencephalogram (EEG) showed generalized slowing in majority of patients (45.5%), with 21.8% interictal epileptiform activity. Patients required lower doses of AEDs to control seizures, gain better seizure control. Common co-morbidities were hypertension and diabetes mellitus.

CONCLUSION

Patients presenting with LOE, should have search for any other cerebrovascular risk factors. Further research is needed to determine the prevalence of oCVD in LOE, and to investigate whether addressing cerebrovascular risk factors in this cohort of patients can reduce the incidence of stroke.

Epilepsy in the elderly: facts and challenges

The incidence of epilepsy in the elderly has increased steadily over the last few decades. In some industrialized countries, one-third of the population is expected to be over the age of 65 in 2030. Therefore, we will face a dramatic increase in the number of elderly patients with epilepsy, many of whom will likely present comorbidities. This increase will put a heavy burden on health care and pension systems. This article focuses on epidemiology, diagnosis and treatment in epilepsies in the elderlies and outlines current research as well as future requirements for research. The diagnosis of epilepsy in the elderly can be difficult and may require long-term video-EEG monitoring. Stroke is the most frequent etiology in epilepsies in the elderlies. Status epilepticus in acute symptomatic epilepsies often results in fatality and may become an increasing health problem. The article also describes the current strategies in antiepileptic drug treatment and epilepsy surgery in the elderly. Novel antiepileptic drugs are necessary as current antiepileptics have strong interaction potentials and harmful side effects, making them ill-suboptimal for treating epilepsy in the elderly.

Treatment and management of epilepsy in the elderly demented patient

Epilepsy and seizures are more frequent in the elderly population than in any other age group. The number of individuals older than 65 is constantly increasing, and dementia is a process that predominantly affects this age group. Several studies have shown that dementia is an important risk factor for developing seizures and epilepsy. Seizure semiology in the elderly demented might differ from that of younger age groups and diagnosis can be complicated further by the variety of other causes of transient changes of alertness and behavior that affects these patients. The pharmacokinetic changes of antiepileptic drugs in the elderly make this group a major therapeutic challenge. Side effects and drug interactions play a major role in the choice of antiepileptic agents. This review intends to summarize the existing data to see whether this can help guide the clinician in the treatment and management of epilepsy in the elderly patient with dementia. Nonpharmacologic therapeutic options are also briefly considered.

Suicide in people with epilepsy: how great is the risk?

PURPOSE

Suicide is more common in populations with epilepsy, but estimates vary concerning the magnitude of the risk. We aimed to estimate the risk using meta-analysis.

METHODS

A literature search identified 74 articles (76 cohorts of people with epilepsy) in whom the number of deaths by suicide in people with epilepsy and the number of person-years at risk could be estimated. Standardized mortality ratios (SMRs) with 95% confidence intervals (CIs) were calculated for each cohort, for groups of cohorts, and for the total population.

RESULTS

The overall SMR was 3.3 (95% CI 2.8-3.7) based on 190 observed deaths by suicide compared with 58.4 expected. The SMR was significantly increased in people with incident or newly diagnosed epilepsy in the community (SMR 2.1), in populations with mixed prevalence and incidence cases (SMR 3.6), in those with prevalent epilepsy (SMR 4.8), in people in institutions (SMR 4.6), in people seen in tertiary care clinics (SMR 2.28), in people with temporal lobe epilepsy (SMR 6.6), in those following temporal lobe excision (SMR 13.9), and following other forms of epilepsy surgery (SMR 6.4). The SMR was significantly low overall in two community-based studies of people with epilepsy and developmental disability.

DISCUSSION

We confirm that the risk of suicide is increased in most populations of people with epilepsy. Psychiatric comorbidity has been demonstrated to be a risk factor for suicide in the general population and in people with epilepsy, and such comorbidity should thus be identified and treated.

A review of sudden unexpected death in epilepsy: prediction of patients at risk

This review attempts to provide up-to-date quantitative data from published reports on sudden unexpected death in epilepsy (SUDEP) appearing on Medline and, especially, to provide a means to predict the probability of SUDEP in a given patient. The mean incidence of SUDEP was 1.8/1000, similar to the median of 1.5. The mean standardized mortality ratio was 6.8, and the mean percentage of SUDEP cases among deaths from epilepsy was 16.6. Seventeen risk factors were identified, each given a value according to the number of studies in the literature that specified that condition as a significant risk. The addition of these 17 values then indicated the risk for a given patient. The author calculated these for a group of 91 patients who died of SUDEP and also for 91 live patients. Many of their values for the different risks were significantly different. The sensitivity of these SUDEP values was 71.3%, the specificity 81.8%, and the positive predictive value 84.6%. A discussion includes the question of whether the death in SUDEP is primarily cardiac or pulmonary and the suggestion that it may be either or both in a given patient. The most important risk factor in this study was noncompliance with antiepileptic medication, and the main message of this study to caregivers is that therapeutic drug levels are crucial to avoid SUDEP.

Management of a first seizure. Special problems: adults and elderly

A first seizure out of a clear blue sky can be a major life-changing event. Careful history-taking and appropriate investigation together with a clear explanation provided to patient and family are an essential requirement. Although for most patients, pharmacotherapy can be withheld and events awaited, there are circumstances where introduction of antiepileptic drug (AED) therapy should be considered. Medical causes of seizures should also be sought and treated. In addition, a first seizure in HIV-positive patients and in those with underlying neurocysticercosis should usually provoke the introduction of AED therapy. Particular problems can occur in patients with a single episode of provoked status epilepticus, a first tonic-clonic seizure during pregnancy and, particularly, an unprovoked event in older and learning disabled people. Treatment following a first seizure should balance risk factors for recurrence with the informed opinion of the patients and their family.

Dentate filter function is altered in a proepileptic fashion during aging

PURPOSE

The elderly have an increased incidence and prevalence for seizure disorders. Further, since up to 50% of these cases have no identifiable antecedent, it has been hypothesized that aging of the central nervous system itself may be epileptogenic. Aged rats, compared to adults, exhibit a greater susceptibility to and severity of seizures associated with hippocampal activation. Whether this aging-related change reflects proconvulsive changes in limbic circuitry is unknown and thus was the focus of this study.

METHODS

Hippocampal slices from adult and aged Fischer 344 rats were examined using electrophysiological techniques. The dentate gyrus was our model region since it is involved with both wet-dog shakes and limbic seizures, and it is affected preferentially with age.

RESULTS

No differences were noted between groups in field potential activity elicited with low frequency stimulation. In contrast, 5-Hz molecular layer stimulation could evoke multiple population spikes in approximately 40% of aged versus 0% of adult slices. Further, recording in CA3 revealed that this stimulation paradigm could elicit multiple spikes in aged, but not adult, slices that frequently evolved into spontaneous epileptiform bursts. This change in the capacity of the dentate to respond to and filter afferent input was associated with an aging-related decrease in the frequency of spontaneous IPSPs and an increased propensity for large amplitude prolonged EPSPs following disinhibition.

CONCLUSIONS

These epileptogenic changes in dentate function and circuitry could contribute to the exacerbated susceptibility for hippocampal seizures in aged rodents, as well as the aging-related decline in spatial learning and memory.

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.

Outcomes in Elderly Patients With Newly Diagnosed and Treated Epilepsy

Epilepsy develops most commonly in the elderly. Seizures can severely affect a senior citizen's quality of life, and despite a growing elderly population with epilepsy, there is a paucity of good clinical data in this age group. To address some of the issues encountered by elderly patients with epilepsy, prospective information from elderly patients attending the Epilepsy Unit at the Western Infirmary in Glasgow, Scotland, was analyzed. Ninety patients, aged 65-93 years, were diagnosed with epilepsy and started on antiepileptic drug (AED) treatment. Neuroimaging was performed in 84 patients (93%), with 69 evaluated via computerized tomography and 15 via magnetic resonance imaging; abnormalities were found in 45 patients (54%). Sixty-eight patients underwent interictal electroencephalography, which revealed epileptiform discharges in 18 patients (26%). Fifty-eight of 90 patients (64%) became seizure free for at least 12 months on modest doses of the first prescribed AED. Seizures remained uncontrolled in 21 patients (23%), and the first AED was withdrawn in 11 patients (12%) because of adverse events. Following pharmacological manipulation, a total of 76 patients (84%) achieved seizure freedom. Patients starting treatment > or =2 years after their first seizure were less likely to achieve seizure control than patients who initiated treatment earlier. Newly diagnosed elderly patients were more likely to remain seizure free on AED treatment than newly diagnosed younger populations (p < 0.001). The majority of patients evaluated had partial-onset seizures, and underlying cerebral atrophy and infarcts were common. Treating an older person with initial AED therapy can be complicated; taking adequate time and communicating clearly are paramount. Although most of the patients evaluated had a positive outcome, all AEDs have some disadvantages in this population. Choice of drug may depend on comorbidity and comedication, among other factors. Initial dosing should be low with a slow titration schedule. A holistic approach to care helps optimize the outcome for elderly people with epilepsy.

Antiepileptic drug use in nursing home residents: A cross-sectional, regional study

The use of antiepileptic drugs (AED), their primary indication, comorbid conditions, and concomitant medications were collected from 565 nursing homes (NH) residents of six NH located around the city of Mainz, Germany representing 5.05% of all NH residents in the area. Data were collected from the electronic pharmacy files and by reviewing all available medical records. Average age was 82.2 +/- 2.4 years, 85.5% were women. Of 565 NH residents 28 (4.96%) received AED therapy, of which in 17 (63%) AED were prescribed for a seizure-related diagnosis. In 76.5% seizure types were unspecified and a distinction in focal and generalized epilepsy was made in only 23.5% of patients. Three patients never had epileptic seizures and in four residents the reason for AED use was unclear. AEDs most frequently prescribed were carbamazepine (37.1%), valproic acid (25.9%), and phenytoin (14.8%). Five patients received benzodiazepines (18.5%), newer generation AED were used in only four (14.8%) cases. Residents on average took n = 5.6 +/- 3.3 other drugs. Opportunities exist for health care professionals to improve the medical management of nursing facility residents receiving AEDs.

Pharmacological outcomes in older people with newly diagnosed epilepsy

BACKGROUND

Old age is the most common time in life to develop epilepsy. Despite this, there are few published data exploring pharmacological outcomes in this population.

METHODS

We analyzed outcomes in 117 older patients (median age, 73; range, 65-92) for whom localization-related epilepsy was newly diagnosed and treatment begun at a single center over a 20-year period.

RESULTS

Seventy-three (62%) patients became seizure-free for at least 12 months on their first AED, with 30 (26%) failing to respond and 14 (12%) not tolerating the treatment. Following pharmacological manipulation, 93 (79%) patients attained remission, 87 (93%) on monotherapy and 6 (7%) on duotherapy. No individual AED was more likely to confer seizure freedom than any other. Patients attaining remission were more likely to have had fewer pretreatment seizures (P=0.0078) than those who did not obtain full seizure control.

CONCLUSION

The prognosis in epilepsy may be better in older than younger people, perhaps reflecting lower lesional epileptogenicity and genetic predisposition.

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.

Aging alters electroencephalographic and clinical manifestations of kainate-induced status epilepticus

PURPOSE

The elderly exhibit an increased risk for developing status epilepticus and status-related morbidity and mortality. However, it is unclear how aging alters the progression of electroencephalographic (EEG) activity and behavioral manifestations during status epilepticus.

METHODS

A repetitive low-dose kainate treatment protocol (2.5 mg/kg/h; i.p.) was used in this study in conjunction with EEG and behavioral monitoring from freely behaving adult (7-8 months) and aged (22-25 months) Fischer 344 rats to assess the effects of aging on status epilepticus.

RESULTS

During kainate treatment, both groups exhibited an increase in EEG power that corresponded with the time course of kainate treatment. However, visual inspection and spectral analysis revealed a reduction of the faster frequencies (12.5-35 Hz) in the EEGs of aged rodents. A similar progression of behavioral manifestations was observed in adult and aged rodents during kainate treatment, although the frequency of preseizure manifestations (e.g., wet-dog shakes; aged rats, 110 events/h vs. adults, 25 events/h; median values) was greater, and latency to onset for any given behavioral manifestation (e.g., class V seizures; aged median, 60 min, vs. adult median, 145 min) was consistently shorter within the aged group.

CONCLUSIONS

These data reveal that aged Fischer 344 rats exhibit altered EEG activity (reduction of higher frequencies) and clinical manifestations during kainate-induced status epilepticus. Taken together, these data indicate an age-related change in seizure onset and spread after exposure to glutamate analogues.

Risk factors for sudden unexpected death in epilepsy: a controlled prospective study based on coroners cases

We performed a controlled prospective study of pathologically verified sudden unexpected death in epilepsy (SUDEP) in a coronial setting, to identify risk factors. We prospectively studied coronial deaths of people with epilepsy in Vic., Australia, during a 21-month period. Fifty SUDEP and 50 subjects with epilepsy who died of other causes (controls) were collected sequentially. Clinical data was obtained shortly after death from questionnaires completed by treating doctors, discussion with family members and coronial files, including police reports of death, autopsy and toxicology reports. Factors assessed were age, sex, duration of epilepsy, type of seizure(s), seizure frequency, symptomatic epilepsy, including post-traumatic epilepsy, presence of structural brain lesion, idiopathic epilepsy, mental retardation, psychiatric illness, including dementia, recent stressful life event, particular antiepileptic drugs (AEDs) and AED polytherapy, compliance with AED treatment, psychotropic drug prescription, alcohol and other substance abuse, place of death and evidence of terminal seizure. The SUDEP group was characterised by younger age and higher proportion found dead in bed and with evidence of terminal seizure compared to controls. The profile of patients at risk for SUDEP are young people with epilepsy. They are most likely to die in sleep and our data support the view that SUDEP is a seizure-related event. This, taken in conjunction with the finding that there was no increased risk associated with a particular AED in monotherapy or multiple AEDs suggests that attempts to better treat patients' epilepsy with AEDs might decrease the risk of SUDEP. Although the literature suggests that SUDEP is more frequent in patients with severe epilepsy, we did not find a correlation with seizure frequency suggesting that other clinical indices may be more important.

[Is epilepsy in the elderly overlooked? An investigation in a home for the aged]

The symptoms of epileptic seizures in old patients differ from those in younger patients. Therefore, these seizures may be misinterpreted as symptoms of other "typical" diseases in old people. In an old people's home, we assessed whether a standardized questionnaire is able to reveal undiagnosed epilepsy in the elderly. Reported sudden falls, loss of consciousness, and cramps were the criteria for further diagnostic procedures. We found epilepsy in 11 of 389 study participants. In four of them (1% of the total sample), the epilepsy was newly diagnosed; five more cases remained unclear. Therefore, the total number of epileptic patients might have been even higher. Most of the reported sudden falls and unconsciousness (89%) were due to internal medical or other neurological or orthopaedic causes. Once these have been excluded, the diagnosis of epilepsy should be considered. The results of our pilot study suggest that epilepsy in old people's homes is often unrecognised. Early diagnosis and treatment of epilepsy in the elderly is important to improve prognosis and social consequences for affected persons.

Systematic review and meta-analysis of incidence studies of epilepsy and unprovoked seizures

PURPOSE

To evaluate the methodology of incidence studies of epilepsy and unprovoked seizures and to assess the value of their findings by summarizing their results.

METHODS

A Medline literature search from January 1966 to December 1999 was conducted. In each selected study, key methodologic items such as case definition and study design were evaluated. Furthermore, a quantitative meta-analysis of the incidence data was performed.

RESULTS

Forty incidence studies met the inclusion criteria. There was considerable heterogeneity in study methodology, and the methodologic quality score was generally low. The median incidence rate of epilepsy and unprovoked seizures was 47.4 and 56 per 100,000, respectively. The age-specific incidence of epilepsy was high in those aged 60 years or older, but was highest in childhood. Males had a slightly higher incidence of epilepsy (median, 50.7/100,000) than did females (median, 46.2/100,000), and partial seizures seemed to occur more often than generalized seizures. Developing countries had a higher incidence rate of epilepsy (median, 68.7/100,000) than did industrialized countries (median, 43.4/100,000). Similar results were found for unprovoked seizures. The incidence of epilepsy over time appears to decrease in children, whereas it increases in the elderly.

CONCLUSIONS

The age-specific incidence of epilepsy showed a bimodal distribution with the highest peak in childhood. No definitive conclusions could be reached for the incidence of unprovoked seizures and other specific incidence rates of epilepsy. More incidence studies with an adequate study methodology are needed to explore geographic variations and time trends of the incidence of epilepsy and unprovoked seizures.

Epilepsy and mortality: a record linkage study in a U.K. population

PURPOSE

To examine patterns of mortality for a population with epilepsy compared with the nonepilepsy population.

METHODS

The study used cross-sectional record linkage, combining an electronic death register with an epilepsy patient register constructed from a variety of routine health data sources collected from 1991 to 1997. The study was conducted in Cardiff and the Vale of Glamorgan, Wales, U.K., and included all deaths recorded between 1993 and 1996.

RESULTS

There were 352 deaths for patients with epilepsy, 2.0% of all deaths. The crude mortality rates for patients with and without epilepsy were 36.2 and 9.9 per 1,000. The Standardised Mortality Ratio was 2.14 (95% CI, 1.74-2.55) for 1996 deaths. The single most common disease group was cancer, accounting for 66 (18.8%) of deaths for people with epilepsy (SMR, 1.47; 95% CI, 1.11-1.82). Significant excesses were demonstrated for cerebrovascular disease, diseases of the digestive system, respiratory diseases, and other causes of death.

CONCLUSIONS

People with epilepsy have an increased mortality over the population as a whole. The main causes of death are those most common in the population as a whole and those that underlie the epilepsy itself.

Survival of patients with epilepsy: an estimate of the mortality risk

PURPOSE

To investigate the extent and causes of the differences in mortality found in studies on mortality in epilepsy based on a quantitative review of the literature.

METHODS

We used MEDLINE database and Cumulative Index Medicus for 1960-2001, Excerpta Medica for 1948-1965, and relevant journals and bibliographies. We selected comparative studies investigating mortality in epilepsy patients conducted in the last 100 years. The Standardized Mortality Ratio (SMR) was selected as primary outcome. Nineteen studies were included. Pooled estimates were precision weighted and tested for homogeneity. Sources of variability between risk estimates were explored by using multivariate fixed-effects models.

RESULTS

SMRs ranged from 1.3 to 9.3. Risk estimates proved heterogeneous (chi-square test statistic: 1,177; df = 18; p < 0.001). The most important determinant was "source population," explaining half of the variance of the estimates (R(2), 0.47; p = 0.006). SMRs in community studies ranged from 1.3 to 3.1, and for institutionalized populations, from 1.9 to 5.1.

CONCLUSIONS

Our results show that the mortality risk in patients with epilepsy is dependent on source population of patients. Within the different source populations, considerable unexplained variance remains. Hence no uniform summary estimate for the elevated mortality could be determined.

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.

Sudden unexpected deaths in epilepsy--where are we now?

In people with uncontrolled chronic epilepsy there is an excess mortality directly attributable to the epilepsy itself. This is largely due to accidental and non-accidental deaths occurring during or immediately after seizures. Most sudden unexpected deaths in epilepsy fall within the latter category. To acknowledge rather than conceal these deaths is essential before prevention strategies can be addressed.

Sudden death in epilepsy: a study of incidence in a young cohort with epilepsy and learning difficulty

Sudden death, often seizure related, may occur in patients with epilepsy. Population-based incidence is probably on the order of 1:1,000/year. The incidence is much higher in selected groups, however. We wished to establish the incidence of sudden unexpected death (SUD) in a young cohort with severe epilepsy and learning difficulties. The study cohort included 310 pupils with epilepsy enrolled at a special residential school between April 1970 and April 1993. The follow-up period totaling 4,135 person-years included a period of residence at the school as well as time after leaving. Age and sex standardized overall mortality ratio was 15.9 [95% confidence interval (CI) 10.6-23.0], with 20 of 28 deaths considered epilepsy related. An incidence of sudden death cases of 1:295/year was noted. All 14 sudden deaths occurred when the pupils were not under the close supervision of the school and most were unwitnessed, which has implications for prevention.

Sudden Death in Epilepsy: An Avoidable Outcome?

In a retrospective survey of mortality among the first 1000 unselected patients referred to the Epilepsy Research Unit at the Western Infirmary in Glasgow between 1985 and 1990, a total of 18 deaths were identified. Three patients had committed suicide and one each had died of status epilepticus in hospital, a subdural haematoma and a myocardial infarction. The remaining 12 deaths (67%) were sudden (median age 32 years; range 22–68 years). Poor seizure control and poor compliance with antiepileptic drug therapy were recorded in only three (25%) of these patients. There was a change in antiepileptic drug regimen in five (28%) in the month before death. Only two (17%) underwent postmortem examination. In nine of the 12 patients dying suddenly, the primary cause of death was not listed as epilepsy but as asphyxia (3), aspiration (2) and one each of ischaemic heart disease, myocardial infarction, asystole and drowning (in the bath). ‘Status epilepticus' was assumed to have been responsible for the other three deaths, two of which were unwitnessed. Sudden death in people with epilepsy is an entity of great concern. Appropriate death certification and mandatory postmortem examination are essential to provide a truer picture of this neglected phenomenon.

Hormones and epilepsy through the lifetime

Hormones influence brain function from gestation throughout life and may affect the seizure threshold by altering neuronal excitability. Estrogen enhances and progesterone diminishes neuronal excitability experimentally, whereas testosterone and corticosteroids have less consistent effects. Hormonal effects in the CNS also depend on the region of brain in which the hormone acts. Sites of action for most steroid hormones include the hypothalamus and limbic cortex, providing a mechanism for modulating behavior and endocrine function. Seizure patterns may change at certain life stages, perhaps as a result of alterations in hormones. At puberty, epilepsy and benign rolandic epilepsy often remit, while juvenile myoclonic and photosensitive epilepsy may arise. Other types of epilepsy do not respond predictably to events in the reproductive life or to advancing age. In some women, fluctuations in hormones over the menstrual cycle appear to increase seizure vulnerability, probably reflecting changes in relative amounts of estrogen and progesterone. Seizure patterns can be altered, for better or worse, during pregnancy. Whether this reflects the effects of hormones or changes in levels of antiepileptic drugs is not resolved. More information is needed about changes in established epilepsy at menopause and in the elderly. Better understanding of endocrine effects on seizures over a lifetime should lead to more effective epilepsy therapies.

A survey of epileptic disorders in southwest France: seizures in elderly patients

An underestimation of epileptic seizures occurring in aged patients is likely. In an epidemiological survey undertaken in Southwest France, the annual incidence rate per 100,000 persons 60 years or older was 127.2 for all seizures (101.3 in persons aged 60 to 69, 150.4 in those aged 70 to 79, and 139.9 in persons 80 years or older). It was 34.1 for symptomatic localization-related and undetermined epilepsies, 16.1 for isolated seizures, and 77.0 for seizures related to an acute situation, such as metabolic derangements, stroke, or head trauma. In this survey, seizures with an onset age of 60 or older represented 28.0% of the confirmed epilepsies, 17.5% of the isolated seizures, and 52.6% of the acute symptomatic seizures. These figures differ dramatically from those in most previous reports concluding that age-specific incidence declined through adult life. They are closer to the data from more recent reports. The main reason for such a high incidence of epileptic seizures in elderly patients is the number of acute symptomatic (or situation-related) seizures. However, even chronic epilepsies increase in frequency in aging persons. Cerebrovascular disease was the most frequently recognized origin (53.9% of the patients with confirmed epilepsies) and brain tumor was found in 32.9% of the patients.

Cardiac and respiratory correlations with unit discharge in epileptic human temporal lobe

We recorded respiratory activity and electrocardiogram (ECG) together with single cell activity from the amygdala and hippocampus of epileptic patients who later received anterotemporal lobectomy. Cross-correlation histograms were used to test for neuronal discharge timing relationships with inspiration or ECG. Linear regression was used to test for correlations of inspiratory time, respiratory period, and heart rate (HR) with tonic unit rate for each breath. Of 129 cells from 16 patients who later had resection, 89 were contralateral and 40 were ipsilateral to the resected lobe. Of the contralateral cells, 19% had a timing relationship with the cardiac cycle and only 1% had such a relationship with the respiratory cycle. Tonic correlations with HR were noted in 22% and with respiratory period and inspiratory time in 11 and 6%. Neither these percentages nor mean discharge rate differed between structures, although variance in rate was much higher on the resected side. Amygdala cells on the resected side showed more correlations with the cardiac cycle (55 vs. 20%), respiratory period (46 vs. 3%), and inspiratory time (27 vs. 7%) and were more likely to show several types of correlation. The results suggest a selective loss of ipsilateral amygdala cells and/or afferents, favoring relationships with cardiac- and respiratory-related systems and a possible synaptic reorganization of remaining cardiorespiratory afferents.