Abstracts

Rationale: Mortality in epilepsy patients is higher in epilepsy patients compared to the general population1. Whether this translates into a reduced life expectancy has not been sufficiently investigated. In this study we aim to present estimates of life expectancy in a cohort of well defined epilepsy patients from a specialized epilepsy outpatient clinic, compared to the general population of the same geographic area and examine how these values change over time.Methods: Adult patients derived from the epilepsy outpatient clinic of Innsbruck Medical University, Austria, diagnosed between 1970-2010 with epilepsy2 within 365 days of first epileptic seizure (incidence cohort), living in the province of Tyrol, Austria,. The same cohort was, in part, used in previous studies1,3,4. Patient data was updated at every returning visit, patients with brain tumor as cause of their epilepsy were excluded from the cohort. Deaths and their primary causes as recorded on death certificates were established via probabilistic record linkage5 to the national death registry in a retrospective manner. In accordance with Austrian law an informed patient consent was not sought. A Weibull model, using sex, age at time of diagnosis, epilepsy etiology, and year of diagnosis co-variants, was fitted and life expectancy estimated based on life tables for the general population of the same geographic area were.Results: Changes in life expectancy in our cohort are presented in tables 1 and 2.Conclusions: When compared to the general population, epilepsy patients showed changes in life expectancy. In the 1970s all patient sub-groups showed a reduced life expectancy maximal in women diagnosed with symptomatic epilepsy with 6.02 years of life lost at time of diagnosis. In the next decades, reductions in lifetime lost gradually decline until they reach values comparable to the general population or even an increased life expectancy of up to 2.61 years in men with cryptogenic epilepsy at time of diagnosis. Furthermore, a gradual reduction in loss of lifetime could be seen with longer duration from time of diagnosis. This outcome represents a novel finding as mortality in epilepsy patients was consistently found to be increased and one previous estimate of life expectancy in a population based epilepsy cohort from UK reported slight decreases in life expectancy in all subgroups analysed6. While this is in accordance with reduced life expectancies in some of the investigated sub-groups in the current study and can be explained by underlying conditions leading to development of epilepsy and increased risk of premature death, a prolonged life expectancy in others was rather unexpected. Reasons remain speculatory, but could be explained by lower mortality due to reduced engagement in risky activities such as driving cars and motorcycles, skiing, mountain climbing, or working in risk-prone professions. In addition, epilepsy patients may profit from more frequent medical follow ups and laboratory testing, which may result in earlier recognition and treatment of other medical conditions. However, further analyses and investigation of this phenomenon is warranted.