Long-term mortality in children and young adults with epilepsy--A population-based cohort study

Abstract

Purpose: Epilepsy is associated with an increased mortality. This study estimates the effects of co-morbid disorders on short-term and long-term mortality and presents cause-specific mortality for children and young adults with epilepsy.

Methods: We established a population-based cohort of 1,855,946 children born in Denmark from 1977 to 2006. Children were followed from the 29th day of life until death, emigration or 31 December 2006. Data was retrieved from Danish longitudinal civil service, health and cause of death registries. Overall, 25,244 persons were diagnosed with epilepsy and 10,647 persons died during 26.2 million person years of follow-up. Among those who died, 803 were diagnosed with epilepsy prior to death. Mortality rate ratio (MRR) was estimated by comparing the mortality rate among persons with epilepsy with the mortality rate in persons without epilepsy.

Results: The mortality among children and young adults with epilepsy was almost 15 times increased compared with persons without epilepsy (MRR: 14.9 (95% CI: 13.9-16.1)). After excluding persons with adverse birth outcomes and persons with comorbid neurological disorders (other than epilepsy), the MRR was still more than four times increased (MRR: 4.20 (95% CI: 3.28-5.30)). Short- and long-term MRRs were particularly high for those diagnosed with epilepsy before 5 years of age (short-term mortality (<1 year); MRR: 41.5 (95% CI: 35.4-48.3), long term mortality (≥ 1 year); MRR: 21.6 (95% CI: 19.5-23.8)). The cumulative mortality 20 years after the first epilepsy diagnosis was 7.6% (95% CI: 6.8-8.4%) among males and 5.8% (95% CI: 5.1-6.5%) among females.

Keywords: Cause of death; Epidemiology; Epilepsy; Health registries; Mortality.