Publication details

Older Age and Longer Epilepsy Duration Do Not Predict Worse Seizure Reduction Outcome after Vagus Nerve Stimulation



Year of publication 2018
Type Article in Periodical
Magazine / Source Journal of Neurological Surgery, Part A: Central European Neurosurgery
MU Faculty or unit

Faculty of Medicine

Keywords epilepsy; vagus nerve stimulation; seizures reduction; responder
Description Introduction We analyzed the results of vagus nerve stimulation (VNS) on older patients and patients with long-lasting epilepsy and included severely intellectually disabled patients. Patients and Methods A total of 103 adults with VNS implanted from 2005 to 2014 were studied. The responder rates, that is, the percentage of VNS patients who responded to VNS, classified as seizure reduction50% (50R) and seizure reduction90% (90R), were compared in defined age groups (< 40 and40 years, and<50 and50 years) and epilepsy duration groups (< 20 and20 years,<30 and30 years, and<40 and40 years) at the 1-year follow-up visit and the last follow-up visit (at least 2 years after surgery). The age distributions and responder rates were also studied in patients with an intellectual disability. Results The analysis did not confirm a significantly lower 50R or 90R rate in patients40,50, or60 years when compared with their younger counterparts, but the 50R rate increase during follow-up care was the lowest in patients50 and60 years. The highest percentage of patients with an intellectual disability in the group<40 years of age did not adversely affect the 50R rate. Longer epilepsy duration was not confirmed as a negative predictor of VNS outcome. There was a significantly higher 50R rate in patients with epilepsy duration20 years (at the last follow-up visit) and a higher 90R rate in patients with epilepsy duration30 years (at the 1-year follow-up visit). The increase in the 50R rate during follow-up care was lower in patients with epilepsy durations30 and40 years. Conclusions The study did not find worse VNS outcomes, as defined by the 50R or 90R rate, in older adult patients or in patients with a longer epilepsy duration. The increasing stimulation effect over time is less marked in older patients and in patients with longer epilepsy duration.