Mortality in adults with newly diagnosed and chronic epilepsy: a retrospective comparative study.

Background: People with epilepsy are at increased risk of premature death compared with the general population. Many clinicians are unsure whether and when this issue should be broached with their patients. We analysed mortality in patients with newly diagnosed and chronic epilepsy over a 20-year period.

Methods: Patients who attended the epilepsy service at the Western Infirmary in Glasgow, UK between 1981 and 2001, with newly diagnosed epilepsy (n=890) or referred after receiving unsuccessful treatment elsewhere (n=2689) were included in the study. Mortality data were obtained from the General Registrar Office for Scotland. Causes of death were ascertained from death certificates and primary care and health authority records. The two patient cohorts were compared with age-matched and sex-matched Scottish comparison groups. Standardised mortality ratios (SMR) were calculated for each epilepsy type, 10-year age band, and cause of death category.

Findings: Newly diagnosed patients had a 42% increase in mortality (SMR 1.42, 95% CI 1.16-1.72) compared with the comparison group. Increased mortality was recorded in those who had not responded to treatment, with no increase in risk observed in patients who were seizure free. In the chronic epilepsy cohort, there was more than double the expected number of deaths (2.05, 1.83-2.26). The incidence of sudden unexpected death in epilepsy was 1.08 and 2.46 per 1000 patient-years in patients with newly diagnosed and chronic epilepsy, respectively. The greatest excess in mortality was reported in patients younger than 30 years.

Interpretation: Mortality risks and preventive strategies should be discussed with patients with epilepsy when treatment fails or is refused despite recurrent seizures.