title: Efficacy of pallidal stimulation in isolated dystonia: a systematic review and meta-analysis.
abstract: The aim of this review was to provide strong clinical evidence of the efficacy of deep brain stimulation (DBS) of the globus pallidus internus (GPi) in isolated inherited or idiopathic dystonia. Eligible studies were identified after a systematic literature review of the effects of bilateral GPi-DBS in isolated dystonia. Absolute and percentage changes from baseline in the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) motor and disability scores were pooled, and associations between treatment effect and patient characteristics were explored using meta-regression. In total, 24 studies were included in the meta-analysis, comprising 523 patients. The mean absolute and percentage improvements in BFMDRS motor score at the last follow-up (mean 32.5 months; 24 studies) were 26.6 points [95% confidence interval (CI), 22.4-30.8] and 65.2% (95% CI, 59.6-70.7), respectively. The corresponding changes in disability score at the last follow-up (mean 32.9 months; 14 studies) were 6.4 points (95% CI, 5.0-7.8) and 58.6% (95% CI, 50.3-66.9). Multivariate meta-regression of absolute scores indicated that higher BFMDRS motor and disability scores before surgery, together with younger age at time of surgery, were the main factors associated with significantly better DBS outcomes at the latest follow-up. Reporting of safety data was frequently inconsistent and could not be included in the meta-analysis. In conclusion, patients with isolated inherited or idiopathic dystonia significantly improved after GPi-DBS. Better outcomes were associated with greater dystonia severity at baseline. These findings should be taken into consideration for improving patient selection for DBS.
authors.affiliation: Division of Neurology, CHU de Grenoble, Université Grenoble Alpes, INSERM U1416, Grenoble, France.
authors.forename: E
authors.initials: E
authors.lastname: Moro
authors.affiliation: Independent biostatistician, Sainte-Anne, Guadeloupe.
authors.forename: C
authors.initials: C
authors.lastname: LeReun
authors.affiliation: Department of Neurosurgery, Hannover Medical School, Hannover, Germany.
authors.forename: J K
authors.initials: JK
authors.lastname: Krauss
authors.affiliation: Department of Neurology, Humanitas Research and University Hospital, Rozzano, Milan, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Albanese
authors.affiliation: General Neurology & Complex Motor Disorders Service, Evelina Children's Hospital, London, UK.
authors.forename: J-P
authors.initials: JP
authors.lastname: Lin
authors.affiliation: Medtronic International Sàrl, Tolochenaz, Switzerland.
authors.forename: S
authors.initials: S
authors.lastname: Walleser Autiero
authors.affiliation: Medtronic International Sàrl, Tolochenaz, Switzerland.
authors.forename: T C
authors.initials: TC
authors.lastname: Brionne
authors.affiliation: Department of Neurology, Salpêtrière Hospital, University Pierre Marie Curie, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Vidailhet
mesh_terms: D046690:Deep Brain Stimulation / Q000379:methods*; D004421:Dystonia / Q000628:therapy*; D020821:Dystonic Disorders / Q000628:therapy*; D005917:Globus Pallidus / Q000503:physiopathology*; D006801:Humans; D016896:Treatment Outcome
keywords: deep brain stimulation; dystonia; globus pallidus; surgery