Abstracts

Rationale: Mortality in epilepsy patients was reported to be two to three times higher than in the standard population. Even though sudden unexpected death in epilepsy patients has been actively discussed over the last years other causes of death are even more prominent in the epilepsy community such as malignant neoplasms of the brain, congenital anomalies, and injury. However, whether some other causes such as suicide or alcohol dependence syndrome are more frequent amongst epilepsy patients remain controversially discussed.Methods: We analyzed causes of death occurring in a hospital-bases cohort containing 66530.65 patient years of confirmed epilepsy, prospectively enrolled from the outpatient epilepsy clinic of the Department for Neurology in Innsbruck, Austria between 1970 and 2009. Causes of death were obtained from the National Institute for Statistics (Statistik Austria), who register the main cause of death as listed on death certificates. Standardized mortality rates were calculated as age-adjusted, comparing our cohort to death rates from the standard population of the same region in five year interval of death year. Cause-groups needed to include at least ten cases to be analyzed and lower range 95% Confidential Intervals (95% CI) needed to be above 1 to be assumed significant. Patients suffering from epilepsy due to brain tumor were excluded from the analysis.Results: Significantly elevated SMRs were found for epilepsy 68.3 (95% CI 52.0-88.1), brain and CNS tumors 14.6 (95% CI 11.0-19.1), congenital anomalies 6.5 (95% CI 2.1-15.2), suicide 4.0 (95% CI 1.8-7.5), alcohol dependence syndrome 3.7 (95% CI 1.7-7.0), malignant neoplasms of esophagus 2.9 (95% CI 1.2-6.0), psychiatric disorders 2.6 (95% CI 1.3-4.6), cerebrovascular disease 2.6 (95% CI 2.2-3.1), pneumonia 2.6 (95% CI 1.6-4.1), external causes 1.9 (95% CI 1.5-2.4), diseases of respiratory system 1.8 (95% CI 1.4-2.), diseases of inner organs 1.7 (95% CI 1.5-1.8), diseases of circulatory system 1.7 (95% CI 1.5-1.9), malignant neoplasms 1.6 (95% CI 1.4-1.8), malignant neoplasms of respiratory tract 1.5 (95% CI 1.1-2.0), ischemic heart disease 1.5 (95% CI 1.3-1.8), and malignant neoplasms without CNS 1.3 (95% CI1.1-1.5).Conclusions: Conditions that can cause epilepsy and epileptic seizures were also the most significant causes of death compared to the standard population, such as congenital anomalies, alcohol dependence syndrome, or cerebrovascular disease. Even though patients suffering from symptomatic epilepsy by a known brain tumor were excluded from the analysis SMR was still highly elevated for this causegroup. This shows the need for better screening and regular controls by imaging methods. Diseases of inner organs on the other hand were only slightly above the standard population. Whether psychiatric illnesses and suicide as ultimo ratio is cause of or result from an epilepsy diagnosis remains unclear, leaving further neuropsychologic research necessary. However, psychological guidance and generous prescription of antidepressant medication and therapy seems inevitable.