Long-term survival after epilepsy surgery compared with matched epilepsy controls and the general population

Abstract

This study evaluates if there was a difference in long-term survival between epilepsy surgery patients, individually matched controls with intractable epilepsy, and controls from the general population. In a cohort study, we compared the survival of patients operated with epilepsy surgery in Norway 1948-1988 with: (1) a control group with prolonged medical treatment for intractable epilepsy individually matched for age, gender, and seizure type (n = 139), and (2) expected mortality for matched individuals in historical cohorts of the general population (n = 196). Survival was compared using Kaplan-Meier curves and stratified proportional hazards analysis. After on average 25 years of observation after surgery, there was no difference in survival between the epilepsy surgery group and the controls with intractable epilepsy (p = 0.18). The risk ratio for death after epilepsy surgery was 0.6 (95% CI 0.4-1.1; p = 0.08) compared with the control group. However, survival of epilepsy surgery patients was lower than that of a matching general population (p < 0.001), with a risk ratio for death of 6.2 (95% CI 3.1-12.6; p < 0.001). In this long-term study of a national cohort of epilepsy surgery patients, we found no beneficial effect of epilepsy surgery on survival compared with a control group of medically treated patients with intractable epilepsy. The mortality after epilepsy surgery was higher than expected in the general population.