title: Vagus nerve stimulation in drug-resistant epilepsy: the efficacy and adverse effects in a 5-year follow-up study in Iran.
abstract: Drug-resistant epilepsy seems like a different disease compared with easy to control epilepsy, and new strategies are needed to help these patients. Vagus nerve stimulation (VNS) therapy is the most frequently used neurostimulation modality for patients with drug-resistant epilepsy who are not eligible for seizure surgery. In this study, we aimed to evaluate the efficacy and adverse effects of VNS in patients with drug-resistant epilepsy in an open-label, prospective, long-term study in Iran. We selected 48 patients with partial-onset drug-resistant epilepsy. Implantations were performed in the neurosurgery department of Loghman Hospital, Tehran, Iran. Follow-up visits were done on monthly bases for 5 years. Forty-four patients completed the study. Mean age of patients was 24.4 years. Mean years of epilepsy history was 14 years. The mean number of anti-epileptic drugs did not significantly change over five years (p = 0.15). There was no exacerbation of epilepsy; however, one patient discontinued his therapy due to unsatisfactory results. Five patient had more than 50 %, and 26 patients (59 %) had 25-49 % reduction in the frequency of monthly seizures persistently. Overall mean frequency of monthly seizures decreased by 57.8, 59.6, 65, 65.9, and 67 %, in 1st, 2nd, 3rd, 4th, and 5th years of follow-up, respectively. Most common side effects were as follows: hoarseness (25 %) and throat discomfort (10 %). We found VNS as a safe and effective therapy for drug-resistant epilepsy, with an approximate long-term decrease in mean seizure frequency of 57.8-67 %. Thus, VNS is recommended for suitable patients in developing countries.
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Pakdaman
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. ali.amini@sbmu.ac.ir.
authors.forename: Ali
authors.initials: A
authors.lastname: Amini Harandi
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Abbasi
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Karimi
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Ali
authors.initials: MA
authors.lastname: Arami
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Seyed Ali
authors.initials: SA
authors.lastname: Mosavi
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Karim
authors.initials: K
authors.lastname: Haddadian
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Omidvar
authors.initials: O
authors.lastname: Rezaei
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Sohrab
authors.initials: S
authors.lastname: Sadeghi
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Guive
authors.initials: G
authors.lastname: Sharifi
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Koroush
authors.initials: K
authors.lastname: Gharagozli
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Parviz
authors.initials: P
authors.lastname: Bahrami
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Farzad
authors.initials: F
authors.lastname: Ashrafi
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Hosein Delavar
authors.initials: HD
authors.lastname: Kasmae
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Amirhossein
authors.initials: A
authors.lastname: Ghassemi
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mehran
authors.initials: M
authors.lastname: Arabahmadi
authors.affiliation: Brain Mapping Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Behdad
authors.initials: B
authors.lastname: Behnam
mesh_terms: D000293:Adolescent; D000328:Adult; D000069279:Drug Resistant Epilepsy / Q000628:therapy*; D004828:Epilepsies, Partial / Q000628:therapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007492:Iran; D008297:Male; D017063:Outcome Assessment, Health Care; D055536:Vagus Nerve Stimulation / Q000009:adverse effects / Q000379:methods*; D055815:Young Adult
keywords: Adverse effects; Drug-resistant epilepsy; Efficacy; Iran; Long-term study; VNS