Epilepsy‐related mortality is low in children: A 30‐year population‐based study in Olmsted County,MN

Purpose: Epilepsy is a common childhood neurologic disorder, affecting 0.5–1% of children. Increased mortality occurs due to progression of underlying disease, seizure‐related accidents, suicide, status epilepticus, aspiration during seizures, and sudden unexplained death in epilepsy (SUDEP). Previous studies show mortality rates of 2.7–6.9 per 1,000 person‐years. Potential risk factors include poor seizure control, intractable epilepsy, status epilepticus, tonic–clonic seizures, mental retardation, and remote symptomatic cause of epilepsy. Few population‐based studies of mortality and SUDEP in childhood‐onset epilepsy have been published. The purpose of this study is to report mortality and SUDEP from a 30‐year population‐based cohort of children with epilepsy. Methods: The Medical Diagnostic Index of the Rochester Epidemiology Project was searched for all codes related to seizure and convulsion in children living in Olmsted County, Minnesota and of ages birth through 17 years from 1980 through 2009. The medical records of these children were reviewed to identify all those with new‐onset epilepsy, and to abstract other baseline and follow‐up information. Potential risk factors including seizure type, epilepsy syndrome, history of status epilepticus, the presence and severity of neurologic impairment, and epilepsy outcome was reviewed. Epilepsy outcome was characterized by seizure frequency, number of antiseizure medications (antiepileptic drugs, AEDs) used, and number of AEDs failed due to lack of efficacy, and epilepsy intractability at 1 year and 2, 3, 5, 10, 15, and 20 years after epilepsy onset. We followed all children through their most recent visit to determine vital status, cause of death, and whether autopsy was performed. Key Findings: From 1980 to 2009, there were 467 children age birth through 17 years diagnosed with epilepsy while residents of Olmsted County, Minnesota, and who had follow‐up beyond the time of epilepsy diagnosis. Children were followed for a median of 7.87 years after the time of diagnosis (range 0.04–29.49 years) for a total of 4558.5 person‐years. Sixteen (3.4%) of the children died, or 3.51 deaths per 1,000 person‐years. Two deaths were epilepsy related (12.5%) for a rate of 0.44 per 1,000 person‐years. One of these children died of probable SUDEP and one died of aspiration during a seizure. The remaining 14 deaths (87.5%) were caused by other complications of underlying disease. Several risk factors for mortality were found, including abnormal cognition, abnormal neurologic examination, structural/metabolic etiology for epilepsy, and poorly controlled epilepsy. Significance: Although mortality in children with epilepsy was higher than what would be expected in the general pediatric population, death occurred significantly more in children with neurologic impairment and poorly controlled epilepsy. Epilepsy‐related death, including SUDEP, was rare and mortality due to epilepsy alone was similar to the expected mortality in the general population (observed deaths = 2, expected deaths = 1.77; standardized mortality ratio 1.13, 95% confidence interval 0.19–3.73, p = 0.86). By contrast, most children died of complications of the underlying neurologic disease or unrelated disease rather than the epilepsy.     

Sudden unexpected death in epilepsy in adults with mental retardation

The medical records of residents of a facility for persons with mental retardation from January 1, 1978, through December 31, 1997, were analyzed to identify incidence of sudden unexpected death for groups of 180 individuals with and 125 without comorbid epilepsy. Eighty deaths were identified, with 55 occurring in the epilepsy group and 25 in the nonepilepsy group. The rate of sudden unexpected death was 1.3 deaths per 1,000 patient years in the nonepilepsy group and 3.6 deaths per 1,000 patient years in the epilepsy group. The risk factors for sudden unexpected death in the epilepsy group were nonambulatory status and poorly controlled seizure disorder (increased seizure rate and increased number of antiepileptic drugs).     

Combined analysis of risk factors for SUDEP

Purpose: To pool data from four published case–control studies of sudden unexpected death in epilepsy (SUDEP) with live controls, to increase the power to determine risk factors. Methods: Case–control studies from the United States, Sweden, Scotland, and England were combined. SUDEP was defined as (1) a history of epilepsy (>1 epileptic seizure during a period of <5 years); (2) death occurring suddenly; (3) death unexpected (i.e., no life‐threatening illness); and (4) death remained unexplained after all investigative efforts, including autopsy. Definite SUDEP required all criteria. Logistic regression analyses adjusted for study. Further analysis simultaneously adjusted for study, age at death, gender, and duration of epilepsy. Key Findings: Of the risk factors that could be analyzed across some or all studies, those that were statistically significant were increased frequency of generalized tonic–clonic seizures (GTCS), use of polytherapy, duration of epilepsy, young age at onset, gender, symptomatic etiology, and lamotrigine therapy. Results persisted when epilepsy onset was younger than 16 years and when it was 16 years or older. In univariate analysis, lamotrigine therapy was associated with significantly increased risk for SUDEP among individuals with idiopathic generalized epilepsy. Significance: This analysis refines the identification of people with epilepsy that are at particular risk of SUDEP. The emerging profile indicates that people with early onset refractory symptomatic epilepsy with frequent GTCS and antiepileptic drug (AED) polytherapy are at higher risk. The results suggest that reduction of the number of GTCS is a priority, of more importance than reducing the number of AEDs. The role of AEDs and other treatment should be analyzed further in future studies.     

Unexpected, unexplained death in epileptic patients.

Thirty-seven cases of unexpected, unexplained death in epileptic patients were recorded by the Allegheny County Coroner's Office during the years 1969 through 1973. In no case was there anatomic or chemical evidence at autopsy sufficient to explain death. All patients had a duration of epilepsy greater than a year. All but two had less than one seizure per month. Blood levels of anticonvulsants at autopsy revealed only three patients with therapeutic levels of the drugs. Almost 50 percent of the cases studied had no demonstrable anticonvulsant. It is suggested that inadequate levels of anticonvulsant drugs are a significant factor associated with unexpected, unexplained death in epileptic patients.     

Sudden unexplained death in children with epilepsy

BACKGROUND: Sudden unexplained death is a significant cause of mortality in people with epilepsy. Risk factors that have been identified include male sex, poor compliance with medications, and antiepileptic drug (AED) polypharmacy. However, these may not apply to the pediatric population in which the causes of epilepsy differ from the adult population. Therefore, risk factors for sudden unexplained death in epilepsy (SUDEP) in children must be evaluated independently from those in the adult population. METHODS: Cases of SUDEP in children less than 18 years of age occurring over a 10-year period in the province of Ontario, Canada, were identified. Records were reviewed for demographic and clinical features and neuropathology findings. RESULTS: Twenty-seven cases of SUDEP in children were identified. Sixty-three percent were male. Age at death ranged from 8 months to 15 years. Fourteen children had symptomatic epilepsy (52%), five had cryptogenic epilepsy (18%), and eight had idiopathic epilepsy (30%). Twelve children were treated with one AED (46%), 10 were on two AED (38%), and three were on three AED (12%). At the time of death, seven children had one serum AED concentration below the therapeutic range (35%) and 12 children had AED levels within the therapeutic range (60%). CONCLUSIONS: This case series represents the largest series of sudden unexplained death in children with epilepsy. At least two previously described risk factors for SUDEP in adults, low serum AED levels at time of death and AED polytherapy, do not appear to be significant in children.     

Early development of intractable epilepsy in children: a prospective study

BACKGROUND: Little is known about early prediction of intractable epilepsy (IE) in children. Such information could help guide the early use of new therapies in selected patients. METHODS: Children with newly diagnosed epilepsy (n = 613) were prospectively identified from child neurology practices in Connecticut (1993--1997) and followed-up for the occurrence of IE (failure of > or = 2 drugs, > or = 1 seizure/month, over 18 months) [corrected]. Etiology and epilepsy syndromes were classified per International League Against Epilepsy guidelines. RESULTS: The median follow-up is 4.8 years, and 599 (97.7%) have been followed for more than 18 months. Sixty children (10.0%) have met the criteria for IE, including 34.6% with cryptogenic/symptomatic generalized, 2.7% with idiopathic, 10.7% with other localization-related, and 8.2% with unclassified epilepsy (p < 0.0001). After multivariable adjustment for epilepsy syndrome, initial seizure frequency (p < 0.0001), focal EEG slowing (p = 0.02), and acute symptomatic or neonatal status epilepticus (p = 0.001) were associated with an increased risk of IE, and age at onset between 5 and 9 years was associated with a lowered risk (p = 0.03). The absolute number of seizures and unprovoked or febrile status epilepticus were not associated substantially with IE. CONCLUSIONS: Approximately 10% of children meet criteria for IE early in the course of their epilepsy. Cryptogenic/symptomatic generalized syndromes carry the highest risk and idiopathic syndromes the lowest. Half of IE occurs in children with nonidiopathic localization-related syndromes. Initial seizure frequency is highly predictive of IE. By contrast, absolute number of seizures and unprovoked or febrile status epilepticus are not.     

Mortality in epilepsy

Both community-based studies and reports from more selected epilepsy populations consistently reveal persons with epilepsy to have a mortality rate two to three times that of the general population. This increased rate is most pronounced in patients with remote symptomatic epilepsy, although many studies also report a significant excess mortality also among those with idiopathic epilepsy. The highest standardized mortality ratios (SMR) are seen in young age groups, mainly due to the low expected mortality in children, and during the first 5-10 years after diagnosis. Many of these observations suggest that the higher mortality is partly related to the underlying disorder causing epilepsy rather than a direct consequence of the seizures. For example, mortality in cerebrovascular diseases is increased, with SMRs ranging from 1.8 to 5.3 in the various studies. Deaths due to neoplasms, and in particular brain tumors, is also increased among patients with epilepsy. Accidents, status epilepticus, and sudden unexpected death (SUD) are more directly seizure-related causes of death. The incidence of such deaths vary considerably depending on the population being studied. While rare among patients with new-onset epilepsy, seizure-related deaths may account for up to 40% of all deaths in patients with chronic epilepsy. SUD is probably the most frequent seizure-related cause of death among young adults with epilepsy, with an SMR more than 20 compared with the general population. Seizure-induced autonomic cardiorespiratory effects have been suggested, but the mechanisms behind SUD are far from fully understood. It appears, however, that the risk of SUD is closely related to seizure frequency, being 40 times higher in patients who continue to have seizures than in those who are seizure-free.     

Sudden unexpected death in epilepsy: a series from an epilepsy surgery program and speculation on the relationship to sudden cardiac death

Sudden unexpected death represents a significant cause of mortality in people with epilepsy. It derives this significance not because it is the most frequent cause of death but because it is apparently a direct consequence of a seizure. The implication is that epilepsy is an inherently lethal disorder. Seven patients who were studied in an epilepsy surgery program died a sudden unexpected death. This incidence of sudden unexpected death was five times higher than the 1-2/1,000 per year reported in the general epilepsy population. Sudden unexpected death shares some of the characteristics associated with sudden cardiac death, which kills 300,000 people in the United States each year. A cardiac arrhythmia, usually ventricular fibrillation, is the most common terminal event for sudden cardiac death and is the leading candidate as the mechanism for sudden unexpected death. Despite this knowledge, little is known on how to identify a high-risk group of patients for sudden death or how these deaths might be prevented.     

Mortality in epilepsy in the first 11 to 14 years after diagnosis: multivariate analysis of a long-term, prospective, population-based cohort

The United Kingdom National General Practice Study of Epilepsy is a prospective, population-based study of newly diagnosed epilepsy. A cohort of 792 patients has now been followed for up to 14 years (median follow-up [25th, 75th percentiles] 11.8 years, range 10.6-11.7 years), a total of 11,400 person-years. These data are sufficient for a detailed analysis of mortality in this early phase of epilepsy. Over 70% of patients in this cohort have developed lasting remission from seizures, although the mortality rate in the long term was still twice that of the general population. The standardized mortality ratio (SMR), the number of observed deaths per number of expected deaths, was 2.1 (95% confidence interval [CI] = 1.8, 2.4). Patients with acute symptomatic epilepsy (SMR 3.0; 95% CI = 2.0, 4.3), remote symptomatic epilepsy (SMR 3.7; 95% CI = 2.9, 4.6), and epilepsy due to congenital neurological deficits (SMR 25; 95% CI = 5.1, 73.1) had significantly increased long-term mortality rates, whereas patients with idiopathic epilepsy did not (SMR 1.3; 95% CI = 0.9, 1.9). This increase in mortality rate was noted particularly in the first few years after diagnosis. Multivariate Cox regression and time-dependent co-variate analyses were utilized for the first time in a prospective study of mortality in epilepsy. The former showed that patients with generalized tonic-clonic seizures had an increased risk of mortality. The hazard ratio (HR), or risk of mortality in a particular group with a particular risk factor compared to another group without that particular risk factor, was 6.2 (95% CI = 1.4, 27.7; p = 0.049). Cerebrovascular disease (HR 2.4; 95% CI = 1.7, 3.4; p < 0.0001), central nervous system tumor (HR 12.0; 95% CI = 7.9, 18.2; p < 0.0001), alcohol (HR 2.9; 95% CI = 1.5, 5.7; p = 0.004), and congenital neurological deficits (HR 10.9; 95% CI = 3.2, 36.1; p = 0.003) as causes for epilepsy and older age at index seizure (HR 1.9; 95% CI = 1.7,2.0; p < 0.0001) were also associated with significantly increased mortality rates. These hazard ratios suggest that epilepsy due to congenital neurological deficits may carry almost the same risk of mortality as epilepsy due to central nervous system tumors and that epileptic seizures subsequent to alcohol abuse may carry almost the same risk of mortality as epilepsy due to cerebrovascular disease. The occurrence of one or more seizures before the index seizure (the seizure that led to the diagnosis of epilepsy and enrolment in the study) was associated with a significantly reduced mortality rate (HR 0.57; 95% CI = 0.42, 0.76; p = 0.00001). Time-dependent co-variate analysis was used to examine the influence of ongoing factors, such as seizure recurrence, remission, and antiepileptic drug use, on mortality rates in the cohort. Seizure recurrence (HR 1.30; 95% CI = 0.84, 2.01) and antiepileptic drug treatment (HR 0.97; 95% CI = 0.67, 1.38) did not influence mortality rate. There were only 5 epilepsy-related deaths (1 each of sudden unexpected death in epilepsy, status epilepticus, burns, drowning, and cervical fracture), suggesting that death directly due to epileptic seizures is uncommon in a population-based cohort with epilepsy.     

Premature mortality of epilepsy in low‐ and middle‐income countries: A systematic review from the Mortality Task Force of the International League Against Epilepsy

To determine the magnitude of risk factors and causes of premature mortality associated with epilepsy in low‐ and middle‐income countries (LMICs). We conducted a systematic search of the literature reporting mortality and epilepsy in the World Bank‐defined LMICs. We assessed the quality of the studies based on representativeness; ascertainment of cases, diagnosis, and mortality; and extracted data on standardized mortality ratios (SMRs) and mortality rates in people with epilepsy. We examined risk factors and causes of death. The annual mortality rate was estimated at 19.8 (range 9.7–45.1) deaths per 1,000 people with epilepsy with a weighted median SMR of 2.6 (range 1.3–7.2) among higher‐quality population‐based studies. Clinical cohort studies yielded 7.1 (range 1.6–25.1) deaths per 1,000 people. The weighted median SMRs were 5.0 in male and 4.5 in female patients; relatively higher SMRs within studies were measured in children and adolescents, those with symptomatic epilepsies, and those reporting less adherence to treatment. The main causes of death in people with epilepsy living in LMICs include those directly attributable to epilepsy, which yield a mean proportional mortality ratio (PMR) of 27.3% (range 5–75.5%) derived from population‐based studies. These direct causes comprise status epilepticus, with reported PMRs ranging from 5 to 56.6%, and sudden unexpected death in epilepsy (SUDEP), with reported PMRs ranging from 1 to 18.9%. Important causes of mortality indirectly related to epilepsy include drowning, head injury, and burns. Epilepsy in LMICs has a significantly greater premature mortality, as in high‐income countries, but in LMICs the excess mortality is more likely to be associated with causes attributable to lack of access to medical facilities such as status epilepticus, and preventable causes such as drowning, head injuries, and burns. This excess premature mortality could be substantially reduced with education about the risk of death and improved access to treatments, including AEDs.     

Pediatric experience with sudden unexplained death in epilepsy at a tertiary epilepsy center

Sudden unexplained death in epilepsy is rare in children, and few studies report risk factors. We reviewed our experience with 17 cases of sudden unexplained death in epilepsy to determine risk factors in children. The charts of all patients with onset of epilepsy at less than age 18 years who suffered sudden unexplained death in epilepsy between August 1992 and April 2004 at our epilepsy center were retrospectively reviewed. Deaths were classified as possible, probable, or definite sudden unexplained death in epilepsy. There were seven cases of definite, nine cases of probable, and one case of possible sudden unexplained death in epilepsy. Generalized tonic-clonic seizures and prone position during sleep were found to be major risk factors. Sudden unexplained death in epilepsy in children and adolescents is associated with convulsive seizures, and aggressive treatment of nocturnal generalized tonic-clonic seizures might help lower the occurrence.     

Circumstances of death in sudden death in epilepsy: interviews of bereaved relatives

OBJECTIVES—To study the circumstances of death in sudden death in epilepsy.
METHODS—Self referred bereaved relatives of patients with epilepsy who had died suddenly were interviewed with information obtained substantiated through other sources—namely, coroners'' officers'' reports, postmortem reports, previous medical records, and EEG reports.
RESULTS—Of 34 cases, 26 were classified as sudden unexpected deaths in epilepsy (SUDEP). Twenty four of 26 cases of SUDEP were unwitnessed. Evidence indicative or suggestive of a seizure was found in most. In 11 of 26 the position of the head was such that breathing could have been compromised. Cases included both localisation related and idiopathic primary generalised epilepsy. Only three were in remission at the time of death. Most relatives expressed the view that they would have preferred to have known that epilepsy could be fatal.
CONCLUSIONS—Although the deaths in question were largely unwitnessed, the available evidence suggested that most cases of SUDEP represented ictal or postictal seizure deaths, occurring in people with a history of generalised tonic clonic seizures, and in both primary generalised and localisation related epilepsy. These interviews highlight the needs of bereaved relatives and their sense of isolation in the face of an entirely unexpected and apparently unexplained loss.

     

Forensic antiepileptic drug levels in autopsy cases of epilepsy

A 1-year retrospective coroner-based forensic examination of causes of death among persons with a history of epilepsy was conducted at the Allegheny County Coroner's Office to evaluate the phenomenon of sudden unexplained/unexpected death in epilepsy (SUDEP), a diagnosis of exclusion. All cases at the Coroner's Office from January 1, 2001 through December 31, 2001, were examined. Review of a total of 1200 autopsied deaths revealed 12 cases with a past medical history of seizure disorder on the death certificate, which listed seizure disorder as the immediate cause of death or contributory cause of the death. Of the 7 men with seizure disorders, 5 were categorized as definite SUDEP and 2 as possible SUDEP. Of the 5 women with seizure disorders, 2 were listed as definite SUDEP, 2 as possible, and 1 as non-SUDEP because the convulsive seizures developed from a grade II glial tumor. Postmortem findings were evaluated for 11 cases; 1 body was decomposed. Toxicological screens were carried out on blood, bile, urine, and eye fluid for all 12. Antiepileptic drug (AED) levels detected in postmortem toxicological analysis were examined. AED levels were determined in 7 cases. Four of 7 had subtherapeutic AED levels, 2 had therapeutic levels, and only 1 victim of SUDEP had levels above the therapeutic range. Five cases had no detectable AED levels. AED levels at autopsy were either absent or subtherapeutic in 9 of 10 SUDEP cases, findings consistent with the likelihood of poor AED compliance. Subtherapeutic levels of AEDs may be a risk factor for SUDEP that could contribute to increased interictal and/or ictal epileptiform activity with associated autonomic dysfunction leading to disturbance of heart rate, heart rhythm, and/or blood pressure.     

Forensic antiepileptic drug levels in autopsy cases of epilepsy

A 1-year retrospective coroner-based forensic examination of causes of death among persons with a history of epilepsy was conducted at the Allegheny County Coroner's Office to evaluate the phenomenon of sudden unexplained/unexpected death in epilepsy (SUDEP), a diagnosis of exclusion. All cases at the Coroner's Office from January 1, 2001 through December 31, 2001, were examined. Review of a total of 1200 autopsied deaths revealed 12 cases with a past medical history of seizure disorder on the death certificate, which listed seizure disorder as the immediate cause of death or contributory cause of the death. Of the 7 men with seizure disorders, 5 were categorized as definite SUDEP and 2 as possible SUDEP. Of the 5 women with seizure disorders, 2 were listed as definite SUDEP, 2 as possible, and 1 as non-SUDEP because the convulsive seizures developed from a grade II glial tumor. Postmortem findings were evaluated for 11 cases; 1 body was decomposed. Toxicological screens were carried out on blood, bile, urine, and eye fluid for all 12. Antiepileptic drug (AED) levels detected in postmortem toxicological analysis were examined. AED levels were determined in 7 cases. Four of 7 had subtherapeutic AED levels, 2 had therapeutic levels, and only 1 victim of SUDEP had levels above the therapeutic range. Five cases had no detectable AED levels. AED levels at autopsy were either absent or subtherapeutic in 9 of 10 SUDEP cases, findings consistent with the likelihood of poor AED compliance. Subtherapeutic levels of AEDs may be a risk factor for SUDEP that could contribute to increased interictal and/or ictal epileptiform activity with associated autonomic dysfunction leading to disturbance of heart rate, heart rhythm, and/or blood pressure.     

Sudden unexpected, unexplained death in epilepsy autopsied patients

Sudden unexpected, unexplained death in epilepsy (SUDEP) has been reported to be responsible for 2 to 17% of all deaths in patients with epilepsy. This study was conducted to determine the circumstances of SUDEP and the autopsy findings in these patients. Fifty-three individuals whose cause of death was related to epilepsy were identified and in 30 cases relatives or friends were interviewed about the circumstances of death and other information which allowed to classify the patients as SUDEP or not. The death certificates were also reviewed. We found 20 cases of SUDEP. Most of them were found dead lying on the bed with no evidence of seizure event, and most of them had pulmonary and/or cerebral edema as the cause of death. The incidence and the risk of SUDEP can only be fully ascertained if all sudden deaths had postmortem examination. Consensus in certifying SUDEP cases would allow better accuracy in national mortality rate.     

Epilepsy in hemiplegic cerebral palsy due to perinatal arterial ischaemic stroke

Aim The aim of this study was to describe the frequency, risk factors, manifestations, and outcome of epilepsy in children with hemiplegic cerebral palsy (CP) due to perinatal arterial ischaemic stroke (AIS). Method The study group comprised 63 participants (41 males, 22 females) from a population‐based CP register whose brain imaging showed perinatal AIS. Information collected included occurrence of neonatal seizures, family history of epilepsy, motor function and epilepsy onset, treatment, and outcome. Electroclinical findings were classified according to seizure semiology, seizure type, and epilepsy syndrome. Results Mean age of participants at the time of study was 10 years 6 months (SD 4y 7mo, range 4–20y). Gross Motor Function Classification System levels I and II were reported in 96% of participants, and Manual Ability Classification System levels I and II were reported in 79% of children. Thirty‐four children (54%) developed epilepsy. Term delivery and more severe motor impairment were associated with epilepsy, but neonatal seizures and family history of epilepsy were not. Initial seizures were epileptic spasms, focal seizures, or myoclonic seizures. Focal seizure semiology suggested Rolandic or occipital seizure origin in the majority of children. Focal epileptic discharges in children with focal seizures had features of idiopathic partial epilepsy. Only 15% of children had active epilepsy 10 years after onset. Interpretation Despite a high incidence of epilepsy in children with hemiplegic CP due to AIS, the prognosis for seizure remission is good. Many children have clinical features, electroencephalography findings, and remission typical of idiopathic partial epilepsy.     

Status epilepticus without an underlying cause and risk of death: a population-based study

OBJECTIVE: To determine the independent effect of status epilepticus (SE) on risk of death. DESIGN: Retrospective cohort study. The increased risk of death after SE has been largely ascribed to the underlying medical condition. It is unknown whether SE itself affects risk of death. We address this question by studying idiopathic/cryptogenic SE. SETTING: Population-based study. PARTICIPANTS: We identified all incident idiopathic/cryptogenic unprovoked seizures in the population of Rochester, Minnesota, from January 1, 1955, through December 31, 1984, and observed them until death, loss to follow-up, or the end of the study. MAIN OUTCOME MEASURES: We compared the risk of death in those with a brief unprovoked seizure (<30 minutes) with risk of death in those with an unprovoked seizure of 30 minutes or longer (SE), using Kaplan-Meier and Cox proportional hazards regression. The standardized mortality ratio was also determined. RESULTS: We ascertained 291 people with a first brief unprovoked seizure and 16 with SE. There were 27 deaths among people with seizure and 5 deaths (all aged > 65 years) among people with SE. Compared with people with seizure, the adjusted relative risk for death in those with SE was 2.4 (95% confidence interval [CI], 0.9-6.3) over 10 years. It was increased 5-fold (relative risk, 5.1; 95% CI, 1.6-15.7) among those older than 65 years and 6-fold among those with SE who later developed epilepsy (relative risk, 6.3; 95% CI, 1.5-26.0). Compared with the general population, the standardized mortality ratio was 2.6 (95% CI, 0.8-5.3) for SE and 1.2 (95% CI, 0.8-1.6) for a first seizure of short duration. CONCLUSION: Idiopathic/cryptogenic SE was associated with an increased risk of death among elderly persons and those who later developed epilepsy.     

Sudden unexpected death in people with epilepsy: a pediatric perspective

The possibility of sudden unexpected death in people with epilepsy (SUDEP) is very frightening for parents of a child with epilepsy. The mechanism for SUDEP is unclear but is probably most commonly related to postictal respiratory insufficiency. Occasionally the cause is a cardiac arrhythmia induced by a seizure. Even though children with epilepsy have an increased risk of death, SUDEP is very rare (1-2/10,000 patient-years). Nearly all of the mortality in children with epilepsy is related to the underlying neurologic disorder, not the seizures. Normal children with epilepsy do not have an increased risk of death compared with the general population. There is no current proven strategy to prevent SUDEP, although its rarity precludes systematic trials. Common sense approaches include identifying patients with cardiac arrhythmias as the cause of misdiagnosed epilepsy and vigorous attempts to control resistant seizure disorders.