Mortality and causes of death among people with convulsive epilepsy in northwestern China

Abstract

Objective: We analyzed mortality and causes of death among people with convulsive epilepsy in rural areas of northwestern China.

Methods: We established a population-based prospective cohort of people with convulsive epilepsy in an epilepsy prevention and management program in rural northwestern China from January 2012 to December 2013. A uniform cause of death questionnaire was used to obtain detailed information on participants who died during the follow-up until December 2016. We calculated the standardized mortality ratios (SMRs) and proportional mortality rate for major causes of death. Cox proportional hazards regression analysis was used to investigate the risk factors associated with mortality.

Results: Among 4296 people with convulsive epilepsy, 216 died during a median follow-up of 59 months. The overall mortality rate was 10.9 per 1000 person-years, and the overall SMR was 2.0. Accidents (25.5%) ranked first in the cause of death, followed by status epilepticus (SE) (22.9%), probable sudden unexpected death in epilepsy (SUDEP) (22.7%), cerebrovascular disease (13.0%), and cardiovascular disease (6.5%). Drowning (10.6%), motor vehicle accidents (13.6%), and falls (4.6%) were the major causes of death by accidents. Female participants had a reduced risk of death from accidents with the hazard ratio (HR) of 0.3 (95% confidence interval (CI): 0.1-0.6). A high risk of death from cerebrovascular disease (HR: 7.2; 95% CI: 2.1-23.6) was found in participants with an onset age of epilepsy older than 16 years.

Significance: The risk of death from convulsive epilepsy in rural northwestern China is twice that of the general population. Accidents, SE, and SUDEP are the leading putative causes of death. Educating people with epilepsy in different regions may help reduce death-related events.

Keywords: Accidents; Cause of death; Convulsive epilepsy; Status epilepticus; Sudden unexpected death in epilepsy.