Dataset Information

External validation of a prognostic model for seizure recurrence following a first unprovoked seizure and implications for driving.

ABSTRACT:

Objective

In the United Kingdom and other European Union countries guidelines for driving following a first unprovoked seizure require the risk of another seizure in the next year to be less than 20%. Using data from one clinical trial, we previously developed a prognostic model to inform driving guidelines. The objective of this work is to externally validate our published model and demonstrate its generalisability.

Methods

A cohort of 620 people with a first unprovoked seizure was used to develop the original model which included variables for aetiology, first degree relative with epilepsy, seizures only while asleep, electroencephalogram, computed tomography or magnetic resonance scan result, and treatment policy. The validation cohorts consisted of 274 (United Kingdom), 305 (Italy), and 847 (Australia) people. The model was evaluated using discrimination and calibration methods. A covariate, missing from the Italian dataset, was handled via five imputation methods. Following external validation, the model was fitted to a pooled population comprising all validation datasets and the development dataset. The model was stratified by dataset.

Results

The model generalised relatively well. All methods of imputation performed fairly similarly. At six months, the risk of a seizure recurrence following a first ever seizure, based on the pooled datasets, is 15% (95% CI: (12% to 18%)) for patients who are treated immediately and 18% (95% CI: (15 to 21%)) otherwise. Individuals can be reliably stratified into risk groups according to the clinical factors included in the model.

Significance

Our prognostic model, used to inform driving regulations, has been validated and consequently has been proven as a valuable tool for predicting risk of seizure recurrence following a first seizure in people with various combinations of risk factors. Additionally, there is evidence to support one worldwide overall prognostic model for risk of second seizure following a first.

SUBMITTER: Bonnett LJ

PROVIDER: S-EPMC4053525 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Publications

External validation of a prognostic model for seizure recurrence following a first unprovoked seizure and implications for driving.

Bonnett Laura Jayne LJ Marson Anthony G AG Johnson Anthony A Kim Lois L Sander Josemir W JW Lawn Nicholas N Beghi Ettore E Leone Maurizio M Smith Catrin Tudur CT

PloS one 20140611 6

<h4>Objective</h4>In the United Kingdom and other European Union countries guidelines for driving following a first unprovoked seizure require the risk of another seizure in the next year to be less than 20%. Using data from one clinical trial, we previously developed a prognostic model to inform driving guidelines. The objective of this work is to externally validate our published model and demonstrate its generalisability.<h4>Methods</h4>A cohort of 620 people with a first unprovoked seizure w ...[more]

PMID: 24919184

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Project description:BACKGROUND:Increasing numbers of reports show the beneficial effects of listening to Mozart music in decreasing epileptiform discharges as well as seizure frequency in epileptic children. There has been no effective method to reduce seizure recurrence after the first unprovoked seizure until now. In this study, we investigated the effect of listening to Mozart K.448 in reducing the seizure recurrence rate in children with first unprovoked seizures. METHODS:Forty-eight children who experienced their first unprovoked seizure with epileptiform discharges were included in the study. They were randomly placed into treatment (n = 24) and control (n = 24) groups. Children in the treatment group listened to Mozart K.448 daily before bedtime for at least six months. Two patients in the treatment group were excluded from analysis due to discontinuation intervention. Finally, forty-six patients were analyzed. Most of these patients (89.1%) were idiopathic in etiology. Seizure recurrence rates and reduction of epileptiform discharges were compared. RESULTS:The average follow-up durations in the treatment and control groups were 18.6 ± 6.6 and 20.1 ± 5.1 months, respectively. The seizure recurrence rate was estimated to be significantly lower in the treatment group than the control group over 24 months (37.2% vs. 76.8%, p = 0.0109). Significant decreases in epileptiform discharges were also observed after 1, 2, and 6 months of listening to Mozart K.448 when compared with EEGs before listening to music. There were no significant differences in gender, mentality, seizure type, and etiology between the recurrence and non-recurrence groups. CONCLUSIONS:Although the case number was limited and control music was not performed in this study, the study revealed that listening to Mozart K.448 reduced the seizure recurrence rate and epileptiform discharges in children with first unprovoked seizures, especially of idiopathic etiology. We believe that Mozart K.448 could be a promising alternative treatment in patients with first unprovoked seizures and abnormal EEGs. Further large-scaled study should be conducted to confirm the effect. TRIAL REGISTRATION:NCT01892605, date: June-19-2013.

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Dataset Information

External validation of a prognostic model for seizure recurrence following a first unprovoked seizure and implications for driving.

Objective

Methods

Results

Significance

Publications

External validation of a prognostic model for seizure recurrence following a first unprovoked seizure and implications for driving.

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