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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., (Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.)

Objective: To assess the hypothesis that use of anterior temporal lobectomy (ATL) for temporal epilepsy has diminished over time., Design: Population-based cohort study., Setting: The Rochester Epidemiology Project based in Olmsted County, Minnesota., Participants: Residents of Olmsted County., Main Outcome Measures: Poisson regression was used to evaluate changes in ATL use over time by sex., Results: Over a 17-year period, from 1993 to 2009, 847ATLs were performed with the primary indication of epilepsy(average, 50 procedures/y). Of these, 26 occurred among Olmsted County residents. The use rates declinedsignificantly between 1993 and 2000 (8 years) and 2001 and 2009 (9 years) according to Poisson regression analysis, from 1.9 to 0.7 per 100 000 person-years(P=.01). The rate of ATL use among Olmsted County residents was 1.2 (95% CI, 0.9 to 2.4) per 100 000 person years of follow-up over this 17-year period. The sex specific rates were 1.6 (95% CI, 0.9 to 2.4) and 0.7 (95%CI, 0.2 to 1.3) per 100 000 person-years for females and males, respectively., Conclusions: In this community-based cohort, the rate of ATL use was 1.2 per 100 000 person-years of followup.Use of this procedure has declined over time; the reasons for this are unknown but do not include referral pattern changes.

Objectives: Previous studies that have assessed the risk of developing epilepsy have failed to account for the competing risk of death, significant in the elderly where epilepsy incidence is highest. We report the lifetime risk for epilepsy, accounting for the competing risk of mortality., Methods: Lifetime risk and cumulative incidence of epilepsy were examined among Rochester, MN, residents between 1960 and 1979. Age-, gender-, and calendar year-specific deaths were obtained for Rochester, MN. Lifetime risk was calculated as the conditional probability of developing epilepsy by a specific age for a person reaching that age who had not yet developed epilepsy. Lifetime risk and cumulative incidence were compared for age and time period., Results: We identified 412 individuals with incident epilepsy diagnosed between January 1, 1960, and December 31, 1979. Lifetime risk was 1.6% to age 50 and 3.0% to age 80; cumulative incidence was 1.7% to age 50 and 3.4% to age 80. Similar differences were seen across epilepsy etiologies. Lifetime risk through 87 years of age increased over time from 3.5% in 1960-1969 to 4.2% in 1970-1979., Conclusions: One in 26 people will develop epilepsy during their lifetime. Lifetime risk provides an estimate of an individual's risk for epilepsy over his or her remaining lifetime, translates into the number of people who are expected to develop epilepsy, and assists health care planners as they estimate service needs for epilepsy.

Purpose: To compare mortality and subsequent unprovoked seizure risk in a population-based study of acute symptomatic seizure and first unprovoked seizure due to static brain lesions., Methods: We ascertained all first episodes of acute symptomatic seizure and unprovoked seizure due to central nervous system (CNS) infection, stroke, and traumatic brain injury (TBI). Subjects were residents of Rochester, Minnesota, identified through the Rochester Epidemiology Project's records-linkage system between 1/1/55 and 12/31/84. Information was collected on age, gender, seizure type, etiology, status epilepticus (SE), 30-day and 10-year mortality, and subsequent episodes of unprovoked seizure., Results: Two hundred sixty-two individuals experienced a first acute symptomatic seizure and 148 individuals experienced a first unprovoked seizure, all due to static brain lesions. Individuals with a first acute symptomatic seizure were 8.9 times more likely to die within 30 days compared to those with a first unprovoked seizure [95% confidence intervals (CI) = 3.5-22.5] after adjustment for age, gender, and SE. Among 30-day survivors, the risk of 10-year mortality did not differ. Over the 10-year period, individuals with a first acute symptomatic seizure were 80% less likely to experience a subsequent unprovoked seizure compared with individuals with a first unprovoked seizure [adjusted rate ratio (RR) = 0.2, 95% CI = 0.2-0.4]., Discussion: The prognosis of first acute symptomatic seizures differs from that of first unprovoked seizure when the etiology is stroke, TBI, and CNS infection. Acute symptomatic seizures have a higher early mortality and a lower risk for subsequent unprovoked seizure. These differences argue against the inclusion of acute symptomatic seizures as epilepsy.

Purpose: Very little is known about short-term mortality after acute symptomatic seizure. One study found an increased mortality in the first year after acute symptomatic seizure, like mortality following acute symptomatic status epilepticus., Methods: We studied mortality in the first 30 days after an acute symptomatic seizure in two cohorts. In Washington Heights, New York City, we reviewed the medical records of all adults aged 20 years and older seen at Columbia Presbyterian Medical Center from January 1, 1990 through December 13, 1994 to identify incident acute symptomatic seizure. In Rochester, Minnesota, the medical records of all Rochester residents were reviewed to identify incident acute symptomatic seizure from January 1, 1965 through December 31, 1984. Case fatality (CF) and standardized mortality ratio (SMR) were calculated for deaths in the first 30 days., Results: A total of 323 adults were identified in Washington Heights and 428 in Rochester. The CF was 20% in both cohorts. CF was greatly increased in the people aged 65 years and older (28.4% in Washington Heights and 40.5% in Rochester) versus younger individuals (17.7% in Washington Heights and 11.2% in Rochester). In both cohorts, the SMR was greatly increased overall (102.1 in Washington Heights and 149.4 in Rochester), and separately for males, females, all etiologies except head trauma in Washington Heights, and younger individuals. In older individuals, the SMR was increased in Washington Heights but not in Rochester., Conclusion: Acute symptomatic seizures are associated with increased mortality in the first 30 days. It is unknown how seizures contribute to this mortality or whether mortality is due solely to the underlying medical condition.

Objective: To determine the population-based incidence of sudden unexplained death in epilepsy (SUDEP) and to determine the risk of SUDEP compared with the general population., Background: Prior studies of SUDEP have described a wide range of incidence and have suffered from selection bias and other methodologic limitations. A population-based study of the incidence of SUDEP has never been performed. Furthermore, the risk of sudden death in the epilepsy population has not been compared with that of the general population., Methods: All deaths in persons whose epilepsy was diagnosed between 1935 and 1994 in Rochester, MN, were reviewed. The rate of SUDEP was compared with the expected rate of sudden death in the general population for patients age 20 to 40 years to determine the standardized mortality ratio (SMR)., Results: We identified nine cases of SUDEP. SUDEP accounted for 8.6% (7 of 81) of the deaths in persons 15 to 44 years of age. The incidence of SUDEP was 0.35 per 1,000 person-years. SMR for SUDEP was 23.7 (95% confidence interval, 7.7 to 55.0) compared with the general population., Conclusions: The incidence of SUDEP in our study was 0.35 per 1,000 person-years. SUDEP was responsible for 1.7% of deaths in our cohort. SUDEP is a rare cause of death in the epilepsy population but exceeds the expected rate of sudden death in the general population by nearly 24 times.

A study of heart disease mortality and morbidity in patients with epilepsy in Rochester, Minnesota, U.S.A., is presented. In a cohort of 725 incident cases of epilepsy followed for approximately 10,000 person-years, 237 deaths and 48 incident cases of ischemic heart disease were noted. Overall, the cohort mortality rate was 2.1 times that of the general population. For those with idiopathic epilepsy, the mortality rate was 1.6 times that of the general population. For ischemic heart disease, the epilepsy cohort experienced a standardized mortality rate (SMR) of 1.6, slightly higher for remote symptomatic than idiopathic epilepsy. For sudden death as the initial manifestation of heart disease, the SMR was 2.3. The ratio was not significantly higher for those with idiopathic epilepsy but was 3.9 for remote symptomatic epilepsy. The findings show much lower incidence rates and relative incidence of sudden death than all of the more recent sudden unexpected death in epilepsy studies. Reasons for this discrepancy are discussed.

Studies based on the Rochester Epidemiology Project medical records-linkage system have provided important insights into the epidemiology of epilepsy. The incidence of all convulsive disorders in Rochester, Minnesota, during a 50-year period exceeded 130 per 100,000 person-years. The age-adjusted incidence of epilepsy was 44 per 100,000 person-years; of a first unprovoked seizure, 61; and of acute symptomatic seizures excluding febrile convulsions, 31. In addition, 2% of the population experienced a febrile convulsion before the age of 5 years. The cumulative incidence of epilepsy through age 74 years was 3.0%, of all unprovoked seizures was 4.1%, and of any convulsive disorder approached 10%. For epilepsy, single unprovoked seizures, and acute symptomatic seizures, the incidence was significantly higher in males than in females, and it was high in the first year of life but highest in those age 75 years or older. For epilepsy alone, approximately 60% of incidence cases experienced partial seizures, and two-thirds had no clearly identified antecedent. Cerebrovascular disease was the most commonly identified antecedent of epilepsy, accounting for 11% of cases. Over time, the incidence of epilepsy and of unprovoked seizures decreased in children and increased in the elderly population. The age-adjusted prevalence of active epilepsy on Jan. 1, 1980, was 6.8 per 1,000 residents. Prevalence was low in the first decade of life, increased to a plateau in the adult years, and further increased in the elderly population. Almost 1.5% of the population older than 75 years of age had active epilepsy. About 25% of prevalence cases had an identified cause; 60% experienced partial epilepsy.

Epidemiologic studies of epilepsy pose a number of methodologic challenges with regard to the definition, classification, and identification of cases. The use of different procedures to address these difficulties makes it imperative to exercise great caution in comparing the results of such studies. Epidemiologic investigations have been consistent in demonstrating that epilepsy is a major neurologic disease throughout the world. Analytic investigations which are beginning to identify risk factors must be continued in order to initiate broad and effective programs of prevention and control.