To determine the incidence of epilepsy among Medicare beneficiaries, and the 5-year mortality associated with incident epilepsy diagnosis.

We performed a retrospective cohort study of Medicare beneficiaries with complete data for the year 2009. Incident epilepsy cases were identified in 2009 using validated ICD-9 and procedure code-based algorithms, and death was assessed through 2014. The incidence of epilepsy was examined by demographic characteristics. Cox regression models were built to examine mortality associated with incident epilepsy, and to determine whether mortality differed by demographic characteristics.

Among the 113, 590 Medicare beneficiaries who were diagnosed with epilepsy in 2009, 56.9% were male, 79.5% were identified as white, and mean age was 76.9 years (SD 8.3). The five-year mortality rate for incident epilepsy was 59.2% (n=67,262).  In adjusted models, blacks had a higher mortality (AHR 1.34, 1.01-1.65).  Female sex was associated with lower mortality (AHR 0.82, 0.81, 0.84).

New onset epilepsy is associated with high 5-year mortality among Medicare beneficiaries. In addition, there are significantly different mortality rates in certain subpopulations—blacks have higher mortality and females have lower mortality. Future studies will be needed to better understand race and sex differences in mortality after a new epilepsy diagnosis.