Long-term outcome of seizure-free patients and risk factors of relapse following antiepileptic drug withdrawal

Objective: This study aimed to investigate the long-term outcome in seizure-free patients and to explore the risk factors of seizure relapse following antiepileptic drug (AED) withdrawal. Methods: This study included 161 patients who had been seizure-free for at least 2 years. These patients were monitored over a follow-up period of at least 3 years or until seizure relapse after AED withdrawal. Patients were grouped into a seizure-free group and a relapse group. Risk factors of seizure relapse were analyzed. Results: During the follow-up period, 72 patients (44.7%) relapsed while 89 patients (55.3%) did not. The average time of relapse was 19.12 +/- 27.17 months after the initiation of AED withdrawal, and majority of cases occurred within the first 24 months of AED withdrawal (73.6%). Univariate analysis showed that the likelihood of relapse was higher in patients with uncontrolled seizures beyond the first 6 months of AED therapy initiation, patients with a history of perinatal injury, patients with multiple seizure types, and patients who had been treated with a combination of AEDs. Multiple logistic regression analysis revealed that uncontrolled seizures beyond the first 6 months of AED treatment and a history of perinatal injury were independent risk factors of seizure relapse. Conclusion: In themajority of cases, epilepsy relapse occurredwithin the first two years after the initiation of AED withdrawal. The independent risk factors of seizure relapse were uncontrolled seizures beyond the first 6 months of AED therapy and cases with a history of perinatal injury. (c) 2018 Elsevier Inc. All rights reserved.