Abstracts

Rationale: Mortality of epilepsy has been part of research for many decades and constantly been described as elevated compared to the general population (Brain 2013 Nov;136(Pt 11):3497). Due to major advances in imaging techniques such as MRI or PET to identify underlying conditions at an earlier stage as well as advances in treatment with new antiepileptic drugs (AED) and broader use of surgical treatment options to achieve better seizure control over the last 20 years, a decline in lethality might be expected. This, however, has not been investigated yet. In the present study we aim to show the development of mortality in a hospital-based cohort of epilepsy patients over almost 3 decades from 1980-2007. Methods: Our cohort derives from a database recording all patients visiting the epilepsy outpatient clinic of Innsbruck Medical University, Austria. Those seen between 1^st January, 1980 and 31^st December, 2007 with a diagnosis of epilepsy (Epilepsia 1989;30(4):389), residence in the province of Tyrol, Austria, and age 18 years or above when last seen at the outpatient clinic, and whose epilepsy diagnoses were established within 365 days of their first ever epileptic seizure (incidence cohort) were included in this study. Patients with suspected brain tumor as cause of their epilepsy were excluded from the cohort. Observation period ended five years after initial treatment in the outpatient clinic. Deceased patients and causes of death as recorded on the death certificate in ICD-codes were identified from the national death registry via probabilistic record linkage (Methods Inf Med 2005;44(5):626). Demographic statistics were computed and standardized mortality rates (SMR) calculated for the first five years following diagnosis. Patients were summarized in 3 groups by year of diagnosis: 1980-89, 1990-99, and 2000-07. The overall population of Tyrol, Austria, was used as reference population. Causes of death comparison of rates was based on Poisson distribution and considered significant at a p-value of 0.05 or below. Statistics was performed using Stata 2012 for Windows (Stata Inc. 2012) and MedCalc (MedCalc Software 2014). Results: Between 1980 and 2007 1073 patients (4,930.7 py), 471 (2,161.4py) women, 602 (2,769.2py) en, were diagnosed with epilepsy within 1 year of their first ever epileptic seizure, 120 of whom died until Dec 31^st, 2012. SMR values are shown in table 1. Significant decreases of causes of death between the 1980s and the 2000s were observed for diseases of the circulatory system where mortality dropped from 3.2 [95% CI 1.8-5.2] in the 80s to 3.1 [95% CI 2.2-4.4] in the 90s to 1.6 [95% CI 0.9-2.6] in the 2000s (p=0.048). Conclusions: We could for the first time show a significant decrease in morality of epilepsy patients since the 1980s in this hospital-based cohort of incidence cases. A reduction in lethality due to diseases of the circulatory system which are common underlying conditions in epilepsy, demonstrates the improvements in patient care in this sub-population.