The efficacy of deep brain stimulation of the anterior nucleus of the thalamus (ANT
DBS) in patients with drug-resistant epilepsy (DRE) was demonstrated in the double-blind
Stimulation of the Anterior Nucleus of the Thalamus for Epilepsy randomized controlled
trial. The Medtronic Registry for Epilepsy (MORE) aims to understand the safety and
longer-term effectiveness of ANT DBS therapy in routine clinical practice.MORE is
an observational registry collecting prospective and retrospective clinical data.
Participants were at least 18 years old, with focal DRE recruited across 25 centers
from 13 countries. They were followed for at least 2 years in terms of seizure frequency
(SF), responder rate (RR), health-related quality of life (Quality of Life in Epilepsy
Inventory 31), depression, and safety outcomes.Of the 191 patients recruited, 170
(mean [SD] age of 35.6 [10.7] years, 43% female) were implanted with DBS therapy and
met all eligibility criteria. At baseline, 38% of patients reported cognitive impairment.
The median monthly SF decreased by 33.1% from 15.8 at baseline to 8.8 at 2 years (p
< 0.0001) with 32.3% RR. In the subgroup of 47 patients who completed 5 years of follow-up,
the median monthly SF decreased by 55.1% from 16 at baseline to 7.9 at 5 years (p
< 0.0001) with 53.2% RR. High-volume centers (>10 implantations) had 42.8% reduction
in median monthly SF by 2 years in comparison with 25.8% in low-volume center. In
patients with cognitive impairment, the reduction in median monthly SF was 26.0% by
2 years compared with 36.1% in patients without cognitive impairment. The most frequently
reported adverse events were changes (e.g., increased frequency/severity) in seizure
(16%), memory impairment (patient-reported complaint, 15%), depressive mood (patient-reported
complaint, 13%), and epilepsy (12%). One definite sudden unexpected death in epilepsy
case was reported.The MORE registry supports the effectiveness and safety of ANT DBS
therapy in a real-world setting in the 2 years following implantation.This study provides
Class IV evidence that ANT DBS reduces the frequency of seizures in patients with
drug-resistant focal epilepsy.MORE ClinicalTrials.gov Identifier: NCT01521754, first
posted on January 31, 2012.
