Medline ® Abstracts for References 5-13

Age has a profound influence on our approach to the convulsive disorders. Age is a variable which is an important determinant for risk factors for epilepsy. Age, as a surrogate of brain maturation, is a determinant of the specific characteristics of the seizure disorder in those with epilepsy, and age-related changes in these manifestations can be identified. Age is a determinant for the occurrence of acute symptomatic seizures in several types of metabolic or central nervous system insults. Age is a determinant for prognosis, whether one considers remission, medication withdrawal in those entering remission, relapse following prolonged remission, or mortality. Last, age per se seems to be a risk factor for epilepsy independent of other factors. This seems particularly true for partial seizures.

The incidence of epilepsy and of all unprovoked seizures was determined for residents of Rochester, Minnesota U.S.A. from 1935 through 1984. Age-adjusted incidence of epilepsy was 44 per 100,000 person-years. Incidence in males was significantly higher than in females and was high in the first year of life but highest in persons aged>or = 75 years. Sixty percent of new cases had epilepsy manifested by partial seizures, and two thirds had no clearly identified antecedent. Cerebrovascular disease was the most commonly identified antecedent, accounting for 11% of cases. Neurologic deficits from birth, mental retardation and/or cerebral palsy, observed in 8% of cases, was the next most frequently identified preexisting condition. The cumulative incidence of epilepsy through age 74 years was 3.1%. The age-adjusted incidence of all unprovoked seizures was 61 per 100,000 person-years. Age- and gender-specific incidence trends were similar to those of epilepsy, but a higher proportion of cases was of unknown etiology and was characterized by generalized onset seizures. The cumulative incidence of all unprovoked seizures was 4.1% through age 74 years. With time, the incidence of epilepsy and of unprovoked seizures decreased in children and increased in the elderly.

The incidence of epilepsy in persons greater than or equal to 60 years was studied during a 5-year period in an urban area. The incidence of patients with definite epilepsy was 77 new cases per year per 100,000 citizens greater than 60 years of age, with a significant excess of male patients. Generalized and partial seizures each accounted for about half of the seizures, but the majority of patients experienced generalization at least once. Of 163 patients with onset of epilepsy during the study period, 152 could manage in their own home, but 97 of these required permanent home help. Marital status, dementia, and focal neurological signs, but not age, influenced patients' social function. A group of patients of the same age with established epilepsy before the study period managed as well or even better, indicating that epilepsy did not significantly influence social function. For both groups, too many patients as compared with the population at risk were economically inactive at the time of admission. Judging from patients' previous occupation, it seems as if patients predominantly came from the lower social classes, indicating that occupational risks may be of ethiological importance.

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.

PURPOSE: Regional variations and temporal trends in the incidence of new-onset epilepsy are clinically important and may offer clues on how to prevent epilepsy.

METHODS: We examined regional differences and secular trends in the incidence of new-onset epilepsy in the Finnish population based on the nationwide full-refundable antiepileptic drug registry and the population registry in the years 1986-2008.

KEY FINDINGS: The overall incidence of epilepsy was significantly higher in eastern Finland than in middle [risk ratio (RR) 1.08 (95% confidence interval, CI 1.05-1.12)), p<0.0001]and western Finland [RR 1.32 (1.30-1.35), p<0.0001]but it was declining from 1986 to 2008 in all regions [RR 0.83 (0.81-0.84), p<0.0001]. The mean annual decline was 0.6%. Although the incidence of epilepsy was falling from 1986 to 2008 in childhood [annual decline 1.9%, RR 0.80 (0.75-0.86), p<0.0001]and in middle age [annual decline 0.8%, RR 0.88 (0.84-0.93), p<0.0001], it increased significantly in the elderly (age 65 years or older) in all of Finland [annual increase 3.5%, RR 1.25 (1.18-1.33), p<0.0001], and particularly in east versus west Finland [RR 1.48 (1.42-1.55), p<0.0001]. As a result, starting with the year 2000, the incidence rate of epilepsy was higher in the elderly than in children for all of Finland.

SIGNIFICANCE: In view of the falling incidence of epilepsy in childhood and middle-age in all of Finland from 1986 to 2008, the significant increase in the incidence of epilepsy in the elderly is of concern. The regional increase of epilepsy may offer clues for allocating resources and, possibly, population epileptogenesis between west and east Finland and for strategies to prevent epilepsy in the elderly.

PURPOSE: To describe seizure types and risk factors among elderly people with newly diagnosed epileptic seizures living on La Réunion, a French Island in the Southern Indian Ocean.

METHODS: We describe an elderly population with newly diagnosed epileptic seizures using data from the EPIREUN study conducted between July 1, 2004 and June 30, 2005. The methodology is described in detail in the EPIREUN study report (Mignard et al., 2009).

KEY FINDINGS: There were 153 single unprovoked seizures (84.1%); their incidence was 278.1 [95% confidence interval (CI) 237.4-325.9]per 100,000. The incidence of newly diagnosed epilepsy was 125.4 (95% CI, 99.1-158.8) per 100,000. Twenty-eight acute symptomatic seizures occurred (15.4%); the incidence was 50.9 (95% CI 35.1-73.7) per 100,000. The annual incidence of newly diagnosed epileptic seizure in the elderly was 330.8 (95% CI 286.1-382.6) per 100,000: 403.0 (95% CI 328.5-494.3) per 100,000 in men and 279.6 (95% CI, 227.4-343.8) per 100,000 in women. Sex had a significant (p = 0.014) effect on incidence: elderly menhad a risk ratio of 1.44 compared to women of developing a newly diagnosed epileptic seizure. The etiology of single unprovoked seizure was as follows: stroke, 77 cases (50.3%); cryptogenic, 36 (23.5%); alcoholism, 10 (6.6%); a combination of several causes such as polypathology, 9 (5.9%); degenerative disease, 6 (4.0%); HIV infection, 2 (2.0%), and undetermined causes (2.7%). Most patients (170; 93.4%) were hospitalized, and 110 (60.8%) were treated. Among patients treated, 49 (44.5%) were given sodium valproate, 25 (22.7%) benzodiazepines, 12 (10.9%) phenytoin, 9 (8.2%) lamotrigine, 8 (7.3%) Trileptal, and 7 (6.4%) gabapentin.

SIGNIFICANCE: Our findings show that the incidences of newly diagnosed epileptic seizures and newly diagnosed epilepsy were high in the elderly population of La Réunion. These incidences were significantly higher in men than in women. These results may be attributable to the high incidence of cerebrovascular diseases and comorbidities in this population.

OBJECTIVE: To determine the prevalence and incidence of epilepsy among U.S. Medicare beneficiaries aged 65 years old and over, and to compare rates across demographic groups.

METHODS: We performed a retrospective analysis of Medicare administrative claims for 2001-2005, defining prevalent cases as persons with≥1 claim with diagnosis code 345.xx (epilepsy) or 2 or more with diagnosis code 780.3x (convulsion)≥1 month apart, and incident cases as prevalent cases with 2 years immediately before diagnosis without such claims. Prevalence and incidence rates were calculated for the years 2003-2005 using denominators estimated from a 5% random sample of Medicare beneficiaries. Results were correlated with gender, age, and race.

RESULTS: We identified 282,661 per year on average during 2001-2005 (a total of 704,243 unique cases overall), and 62,182 incident cases per year on average during 2003-2005. Average annual prevalence and incidence rates were 10.8/1,000 and 2.4/1,000. Overall, rates were higher for black beneficiaries (prevalence 18.7/1,000, incidence 4.1/1,000), and lower for Asians(5.5/1,000, 1.6/1,000) and Native Americans (7.7/1,000, 1.1/1,000) than for white beneficiaries (10.2/1,000, 2.3/1,000). Incidence rates were slightly higher for women than for men, and increased with age for all gender and race groups.

CONCLUSIONS: Epilepsy is a significant public health problem among Medicare beneficiaries. Efforts are necessary to target groups at higher risk, such as minorities or the very old, and to provide the care necessary to reduce the negative effects of epilepsy on quality of life.

BACKGROUND: Sardinia, insular Italy, represents a particular epidemiological setting to investigate polyfactorial diseases, by virtue of its phylogeny and geographic isolation over time and of a well-established network of health operators and information systems. We present the first prevalence study of epilepsy conducted on a large Sardinian population by means of multiple source ascertainment.

METHODS: Cases were ascertained in the province of Sassari (population of 333,576) for the period between January 1, 2000 and December 31, 2008 based on records from (a) the District Center for Epilepsy, (b) the District Health Information System Unit, and (c) the neurologists practicing within the National Health System.

RESULTS: The total crude prevalence of active epilepsy on December 31, 2007 was 6.62 per 1,000 (95% CI 5.3-7.9), 6.51 in men (95% CI 5.4-7.6), and 6.73 in women (95% CI 5.7-7.7). The highest prevalence (8.78 per 1,000) was estimated in the elderly (≥65 years). 50.5% were symptomatic epilepsies. Of these, over 50% were secondary to cerebrovascular disorders in the elderly.

CONCLUSIONS: The epidemiological behavior of prevalence of active epilepsy in Sardinia appears to be in line with that of other developed countries, despite the role that population-specific genetic and environmental factors exert in modulating the risk for other neurological diseases. The action of (exogenous) factors commonly distributed in western populations, also influencing, at least partially, the epidemiological patterns of epilepsy in Sardinians, should not be ruled out.

OBJECTIVE: To determine the prevalence, incidence, and predictors of epilepsy among older adults in the Cardiovascular Health Study (CHS).

METHODS: We analyzed data prospectively collected in CHS and merged with data from outpatient Medicare administrative claims. We identified cases with epilepsy using self-report, antiepileptic medication, hospitalization discharge ICD-9 codes, and outpatient Medicare ICD-9 codes. We used Cox proportional hazards regression to identify factors independently associated with incident epilepsy.

RESULTS: At baseline, 42% of the 5,888 participants were men and 84% were white. At enrollment, 3.7% (215 of 5,888) met the criteria for prevalent epilepsy. During 14 years of follow-up totaling 48,651 person-years, 120 participants met the criteria for incident epilepsy, yielding an incidence rate of 2.47 per 1,000 person-years. The period prevalence of epilepsy by the endof follow-up was 5.7% (335 of 5,888). Epilepsy incidence rates were significantly higher among blacks than nonblacks: 4.44 vs 2.17 per 1,000 person-years (p<0.001). In multivariable analyses, risk of incident epilepsy was significantly higher among blacks compared to nonblacks (hazard ratio [HR]4.04, 95% confidence interval [CI]1.99-8.17), those 75 to 79 compared to those 65 to 69 years of age (HR 2.07, 95% CI 1.21-3.55), and those with history of stroke (HR 3.49, 95% CI 1.37-8.88).

CONCLUSIONS: Epilepsy in older adults in the United States was common. Blacks, the very old, and those with history of stroke have a higher risk of incident epilepsy. The association with race remains unexplained.