Two-year mortality and seizure recurrence following status epilepticus in Auckland, New Zealand: A prospective cohort study

PURPOSE: To document the 2-year mortality and seizure recurrence rate of a prospective cohort of patients identified with status epilepticus (SE).

METHODS: Patients presenting to any hospital in the Auckland region between April 6 2015, and April 5 2016, with a seizure lasting 10 min or longer were identified. Follow up was at 2 years post index SE episode via telephone calls and detailed review of clinical notes.

RESULTS: We identified 367 patients with SE over the course of one year. 335/367 (91.3 %) were successfully followed up at the 2-year mark. Two-year all-cause mortality was 50/335 (14.9 %), and 49/267 (18.4 %) when febrile SE was excluded. Two-year seizure recurrence was 197/335 (58.8 %). On univariate analyses, children (preschoolers 2 to < 5 years and children 5 to < 15 years), Asian ethnicity, SE duration <30 mins and acute (febrile) aetiology were associated with lower mortality, while older age >60 and progressive causes were associated with higher mortality on both univariate and multivariate analyses. Age < 2 years and acute aetiology were associated with lower seizure recurrence, while non convulsive status epilepticus (NCSE) with coma and a history of epilepsy were associated with higher seizure recurrence. On multivariate analyses, a history of epilepsy, as well as having both acute and remote causes were associated with higher seizure recurrence.

CONCLUSIONS: All-cause mortality in both the paediatric and adult populations at 2 years was lower than most previous reports. Older age, SE duration ≥30 mins and progressive aetiologies were associated with the highest 2-year mortality, while febrile SE had the lowest mortality. A history of epilepsy, NCSE with coma, and having both acute and remote causes were associated with higher seizure recurrence at 2 years. Future studies should focus on functional measures of outcome and long-term quality of life.