EpiNet study of incidence of status epilepticus in Auckland, New Zealand: Methods and preliminary results

Abstract

The EpiNet project has been commenced to facilitate investigator-led collaborative research in epilepsy. A new Web-based data collection tool has been developed within EpiNet to record comprehensive data regarding status epilepticus and has been used for a study of status epilepticus in Auckland, New Zealand. All patients aged >4 weeks who presented to any of the five public hospitals and the major private hospital within Auckland city (population = 1.61 million) with an episode of status epilepticus between April 6, 2015 and April 5, 2016 were identified using multiple overlapping sources of information. For this study, status epilepticus was defined as any seizure exceeding 10 minutes in duration, or repeated seizures lasting >10 minutes without recovery between seizures. Patients who had either convulsive or nonconvulsive status epilepticus were included. Episodes of status epilepticus were classified according to the 2015 International League Against Epilepsy ILAE status epilepticus classification. A total of 477 episodes in 367 patients were considered as definite or probable status epilepticus; 285 episodes (62%) lasted >30 minutes, which is the duration that has previously been used for epidemiological studies of status epilepticus.

Status epilepticus in Auckland, New Zealand: Incidence, etiology, and outcomes

“…A record was created in the Status Epilepticus registry in EpiNet for 651 episodes of possible SE, occurring in 508 patients. After review, 477 episodes of SE were confirmed in 367 patients (see Figure ) …”

“…Our aim was to perform a prospective study in which we would identify all patients with SE when they presented to hospital; however, we identified only 72% of cases during or immediately following the episode of SE. This was despite intensive efforts to notify all clinicians treating patients with SE of the study . The priority of the treating clinicians was to terminate the SE as rapidly as possible, with reporting of SE of secondary importance.…”

“…The study was conducted at the five public hospitals and the major private hospital in greater Auckland. Details regarding the methods used to identify patients have been published previously . In summary, we identified all patients older than 4 weeks who had seizures that lasted for 10 minutes or longer, or repeated seizures lasting 10 minutes or longer without recovery.…”

“…For the purposes of this study, an episode of SE was considered to have finally terminated once a patient had been seizure‐free for 6 hours; this 6‐hour rule is not part of the ILAE SE classification, but was an arbitrary but pragmatic choice that was reached by consensus among the investigators. We therefore calculated an initial duration and a final duration of SE . However, we have only considered the initial duration in this report when determining the duration of the SE and the 10‐minute and 30‐minute SE incidence.…”

Status epilepticus in Auckland, New Zealand: Treatment patterns and determinants of outcome in a prospective population‐based cohort

“…The original cohort description including methods, incidence, etiology, and outcomes of this population have been published previously. 1,9 Most cases were identified prospectively, but the study also included patients identified following retrospective chart review to capture all episodes of SE presenting within the Auckland region. Data were recorded into a specially created form in the EpiNet database.…”