Mortality in adults with newly diagnosed and chronic epilepsy: a retrospective comparative study

BACKGROUND: People with epilepsy are at increased risk of premature death compared with the general population. Many clinicians are unsure whether and when this issue should be broached with their patients. We analysed mortality in patients with newly diagnosed and chronic epilepsy over a 20-year period. METHODS: Patients who attended the epilepsy service at the Western Infirmary in Glasgow, UK between 1981 and 2001, with newly diagnosed epilepsy (n=890) or referred after receiving unsuccessful treatment elsewhere (n=2689) were included in the study. Mortality data were obtained from the General Registrar Office for Scotland. Causes of death were ascertained from death certificates and primary care and health authority records. The two patient cohorts were compared with age-matched and sex-matched Scottish comparison groups. Standardised mortality ratios (SMR) were calculated for each epilepsy type, 10-year age band, and cause of death category. FINDINGS: Newly diagnosed patients had a 42% increase in mortality (SMR 1.42, 95% CI 1.16-1.72) compared with the comparison group. Increased mortality was recorded in those who had not responded to treatment, with no increase in risk observed in patients who were seizure free. In the chronic epilepsy cohort, there was more than double the expected number of deaths (2.05, 1.83-2.26). The incidence of sudden unexpected death in epilepsy was 1.08 and 2.46 per 1000 patient-years in patients with newly diagnosed and chronic epilepsy, respectively. The greatest excess in mortality was reported in patients younger than 30 years. INTERPRETATION: Mortality risks and preventive strategies should be discussed with patients with epilepsy when treatment fails or is refused despite recurrent seizures.     

Evolution over time of SUDEP incidence: A nationwide population‐based cohort study

Prompted by a recent report on declining incidence of sudden unexpected death in epilepsy (SUDEP) following implantation of a vagus nerve stimulator (VNS), we analyzed SUDEP risk over 6 years in a population‐based cohort of 60 952 epilepsy patients in Sweden. All deaths from July 1, 2006 through December 31, 2011, were identified. Those with epilepsy mentioned on the death certificate were adjudicated for SUDEP using medical records and autopsy reports. In all, 292 SUDEP cases were identified. Comparing the first years (2006‐2007) with the subsequent 4 years (2008‐2011), the crude and standardized (to the US 2000 population) incidence of SUDEP (whether or not possible SUDEP was included) was significantly lower during the second time period; Incidence rate ratios based on standardized rates was estimated at 0.76 (95% confidence interval [CI] 0.60‐0.97, P = .027) for SUDEP. The incidence of SUDEP decreased by 7% per year during the 6‐year follow‐up. Our data thus suggest that, for unknown reasons, incidence of SUDEP decreases with duration of follow‐up. This has implications for patient counseling as well as for the design of studies attempting to assess the effectiveness of an intervention against SUDEP, which clearly needs to include a control group.     

A population‐based study of newly diagnosed epilepsy in infants

Purpose: Most published data on infants presenting with epilepsy originate from hospital/specialist clinic settings and may therefore not be representative of the general population. We carried out a population‐based study to estimate the incidence of epilepsy onset in infants, to characterize the range of phenotypes and associated structural brain abnormalities, and to determine whether specific epilepsy diagnoses could be established at onset. Methods: Children between 1 and 24 months of age with new‐onset epilepsy were ascertained over 13 months from the residents in 15 boroughs of North London. Classification based on clinical information, electroencephalography (EEG), and neuroimaging data was undertaken independently by two pediatric neurologists. Neuroimages were reviewed by two neuroradiologists blinded to clinical details. Key Findings: A total of 57 children were enrolled giving an ascertainment‐adjusted incidence of 70.1 (95% CI [56.3, 88.5])/100,000 children ≤2 years of age/year (ascertainment 76%). The incidence was highest among Asian children. An electroclinical syndrome was identified in 24 (42%) cases of which 21 were epileptic encephalopathies. Magnetic resonance (MR) images of 51 cases (89% of the total cohort) were reviewed. These demonstrated positive findings in 37 (72%) of 51 cases, of which 26 (51%) of 51 were etiologically relevant, and included developmental malformations in 11 (21%) of 51. Significance: In a population setting infantile onset epilepsy presents mostly with complex phenotypes commonly associated with structural brain abnormalities. Routine MR imaging at presentation is therefore justified. However, identification of specific electroclinical syndromes remains difficult at onset.     

Long‐term employment of adults with childhood‐onset epilepsy: A prospective population‐based study

Purpose: Our aim was to determine the long‐term employment and predictive factors in adults with childhood‐onset epilepsy living in the community. Methods: A population‐based incidence cohort of 144 children prospectively followed since their first unprovoked seizure before the age of 16 years up to a mean age of 48. Results: At a mean age of 23 years (range 18–35 years) 85 (71%) of 119 patients living in the community were employed. Predictive of employment at a mean age of 23 were normal intelligence [odds ratio (OR) 14.5, 95% confidence interval (CI) 4.5–46.8, p < 0.01], vocational education (OR 15.2, 95% CI 2.9–79.9, p < 0.01), and age at onset of epilepsy older than 6 years (OR 4.9, 95% CI 1.3–19.2, p = 0.02). At the mean age of 48 years (range 43–59 years), 45 (59%) of 76 patients living in the community were employed, as were 63 (78%) of 81 controls (patients vs. controls, p = 0.01). In 40 (53%) of 76 surviving patients employed between age 23 and 48, four factors were found to predict employment: normal intelligence (OR 15.8; 95% CI 2.4–102.4, p < 0.01), having offspring (OR 6.1; 1.5–25.0, p = 0.01), uninterrupted 5‐year terminal remission (5YTR) from age 23 to age 48 (OR 4.8; 1.1–19.9, p = 0.03), and no history of status epilepticus (OR 12.8; 1.8–90.9, p = 0.01). Conclusions: Normal intelligence, onset of epilepsy at age older than 6, and good vocational education appear to predict employment in early adulthood. Normal intelligence, having offspring, uninterrupted remission, and no history of status epilepticus appear to predict lasting employment into middle age.     

A descriptive study of epilepsy in the district of El Salvador, Chile, 1984–1988

To describe the epidemiological characteristics of epilepsy in a northern area of Chile, an investigation was conducted in four localities in the province of Copiapó (population of 17,694). Based on 314 cases of active epilepsy, the prevalence per 1000 at June 30, 1988 was 17.7. The average annual incidence for the period 1984-1988 was 113 per 100,000. Partial seizures were the most frequent type of seizure diagnosed (54.1%). Antecedents considered as possible etiological factors were found in 29.9% of cases. According to age of onset, 64.6% had their first attack before 15 years. Middle and low socioeconomic classes had higher prevalence rates of epilepsy. We compare our results with previous Latin-American studies.     

Cerebellar volumes in newly diagnosed and chronic epilepsy

Cerebellar atrophy is assumed to be a common finding in patients suffering from epilepsy. Anticonvulsants as well as seizure activity itself have been considered to be responsible for it but many studies have addressed these questions in specialised centres for epilepsy thus having a referral bias towards patients with severe epileptic syndromes. The purpose of this study was: 1. To develop a quantitative method on 3D-MRI data to achieve volume or planimetric measurements (of cerebrum, cerebellum and cerebellar substructures). 2. To investigate the prevalence of cerebellar atrophy (and substructure atrophy) in a prospectively investigated population-based cohort of patients with newly diagnosed and chronic epilepsy. 3. To quantify cerebellar atrophy in clinic-based patients, who had had atrophy previously diagnosed on routine visual MRI assessment. 4. To correlate the measures of atrophy with clinical features in both patient groups. A total of 57 patients with either newly diagnosed or chronic active epilepsy and 36 control subjects were investigated with a newly developed semiautomated method for cerebral as well as cerebellar volume measurements and substructure planimetry, corrected for intracranial volume. We did not find any significant atrophy in the population-based cohort of patients with newly diagnosed epilepsy or with chronic epilepsy. Visually diagnosed cerebellar atrophy was mostly confirmed and quantified by volumetric analysis. The clinical data suggested a correlation between cerebellar atrophy and the duration of the seizure disorder and also the total number of lifetime seizures experienced and the frequency of generalised tonic-clonic seizures per year. Volumetry on 3D-MRI yields reliable quantitative data which shows that cerebellar atrophy might be common in severe and/or longstanding epilepsy but not necessarily in unselected patient groups. The results do not support the proposition that cerebellar atrophy is a predisposing factor for epilepsy but rather are consistent with the view that cerebellar atrophy is the aftermath of epileptic seizures or anticonvulsant medication. Received: 26 September 2001, Received in revised form: 15 February 2002, Accepted: 15 April 2002 Present address: Dept. of Neurology, Friedrich-Schiller University, 07740 Jena, Germany, Tel.: +49-36 41/93 67 64, Fax: +49-36 41/93 46 99, E-Mail: hagemann@med.uni-jena.de Correspondence to G. Hagemann, MD     

A population‐based family study of minor depression

Background: There is a paucity of research on whether minor depression is a familial disorder. Methods: We conducted a population‐based family study of minor depression in which subjects were interviewed using the Diagnostic Interview Schedule (DIS). Minor depression only (MDO) was diagnosed if there was a lifetime history of what the DIS refers to as a depressive “spell” and no lifetime history of either Diagnostic and Statistical Manual of Mental Disorders, Third Edition, major depression or dysthymia. There were 71 probands with a lifetime history of MDO; 577 controls with no lifetime history of MDO, major depression, or dysthymia; and 1,539 first‐degree relatives (FDRs). Logistic regression was performed with the presence/absence of MDO in a proband/control as the “exposure” and MDO in an FDR as the “outcome”. Results: The odds ratio for the association between MDO in a proband and MDO in an FDR, after adjusting for age and sex of the FDR, was 1.55 (95% confidence interval: 0.93–2.58; P=.093). The study had 80% power to detect an odds ratio as small as 1.97, which is in the range of odds ratios seen for the familial aggregation of major depression. Conclusions: MDO does not appear to be a familial disorder, raising questions about the validity of “minor depression” as a distinct psychiatric syndrome. Depression and Anxiety, 2009. © 2009 Wiley‐Liss, Inc.     

Incidence of Guillain‐Barré syndrome in Chile: a population‐based study

The Guillain‐Barré syndrome (GBS) incidence rate (IR) varies between 0.16 and 3.00 cases per 100,000 inhabitants. Little data exist on the epidemiology of GBS in Latin American countries. Our objective was to describe GBS epidemiology based on a national database in a Latin American country and to contribute to the global map of GBS epidemiology. This was a retrospective study that included all reported GBS cases in Chile between 2001 and 2012. Gender, age, seasonal occurrence, and geographical distribution were analyzed. A total of 4,158 GBS cases were identified from 19,513,655 registries. The mean age was 37 ± 24 years, and 59% of patients were male (male to female ratio of 1.5 : 1). Gender IR was 2.53/100,000 for males and 1.68/100,000 for females. The overall standardized IR was 2.1/100,000, although this varied between 1.61/100,000 (2001) and 2.35/100,000 (2010). The seasonal distribution was as follows: autumn 22%; winter 25%; spring 27%; and summer 26%. The geographical IR were as follows: far North 1.49/100,000; North 1.94/100,000; Central 1.97/100,000; South 3.18/100,000; and far South 2.78/100,000. The reported IR of GBS in Chile was similar to other studies based on national databases. In Chile, IR was greater in men and in the south.