Treatment response and its predictors among epilepsy patients: a retrospective cohort study

Abstract Background Epilepsy is a chronic neurologic disease with variable treatment responses. To design effective epilepsy treatment strategies, it is important to understand treatment responses and predictive factors. However, there are fewer data available in limited resource settings including Ethiopia. Objectives To assess treatment response and its predictors among adult epilepsy patients in Jimma university medical center, Ethiopia. Method and Materials A retrospective cohort study was conducted among 404 adult patients newly diagnosed with epilepsy and receiving antiepileptic medication between May 2010 to May 2015. Demographic, clinical, and outcome data of epilepsy patients with a follow-up of at least two years were collected. Data was entered into Epidata software and imported into the statistical package for the social sciences (IBM SPSS Statistics for Windows, Version 21.0. Armonk, NY: IBM Corp) for analysis. Cox regression was used to identify independent predictors of seizure remission. Result A total of 404 study participants were followed for 1579.25-person years (median 44.0 months). Of them, 64.6% remained seizure-free for at least one year. High frequency of pre-treatment seizure (adjusted hazard ratio [AHR]= 0.716, 95% CI: 0.558–0.919), poor early response (AHR= 0.339, 95% CI: 0.256–0.449), poor adherence (AHR= 0.719, 95% CI 0.546–0.942) and being on polytherapy (AHR= 0.563, 95% CI: 0.420–0.756) were significant predictors of poor seizure remission. Conclusion Only about two third of the patients achieved a one-year seizure remission period. High pre-treatment seizure frequency, poor early response, being on polytherapy and nonadherence to antiepileptic drugs were the independent predictors of poor seizure remission. Early identification and prediction of patients likely to be unresponsive based on the present findings need to be considered.