The Efficacy and Predictors of Using GPi-DBS to Treat Early-Onset Dystonia: An Individual Patient Analysis
Wenxiu Chen, Houyou Fan, Guohui Lu
Abstract
Objective. To compare the efficacy in patients with different genotypes, identify the potential predictive factors, and summarize the complications of globus pallidus deep brain stimulation (GPi-DBS) treating early-onset dystonia. Methods. Three electronic databases (PubMed, Embase, and Cochrane databases) were searched with no publication data restriction. The primary outcomes were the improvements in Burke–Fahn–Marsden Dystonia Rating Scale motor (BFMDRS-M) and disability (BFMDRS-D) score. Pearson’s correlation coefficients and a metaregression analysis were used to identify the potential predictive factors. This article was registered in Prospero (CRD42020188527). Results. Fifty-four studies (231 patients) were included. Patients showed significant improvement rate in BFMDRS-M (60.6%, <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" id="M1"> <a:mi>p</a:mi> <a:mo><</a:mo> <a:mn>0.001</a:mn> </a:math> ) and BFMDRS-D (57.5%, <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" id="M2"> <c:mi>p</c:mi> <c:mo><</c:mo> <c:mn>0.001</c:mn> </c:math> ) scores after treatment with GPi-DBS. BFMDRS-M score improved greater in the DYT-1-positive ( <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" id="M3"> <e:mi>p</e:mi> <e:mo>=</e:mo> <e:mn>0.001</e:mn> </e:math> ) and DYT-11-positive ( <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" id="M4"> <g:mi>p</g:mi> <g:mo>=</g:mo> <g:mn>0.008</g:mn> </g:math> ) patients compared to DYT-6-positive patients. BFMDRS-D score improved greater in the DYT-11 (+) compared to DYT-6 (+) patients ( <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" id="M5"> <i:mi>p</i:mi> <i:mo>=</i:mo> <i:mn>0.010</i:mn> </i:math> ). The relative change of BFMDRS-M ( <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" id="M6"> <k:mi>p</k:mi> <k:mo>=</k:mo> <k:mn>0.002</k:mn> </k:math> ) and BFMDRS-D ( <m:math xmlns:m="http://www.w3.org/1998/Math/MathML" id="M7"> <m:mi>p</m:mi> <m:mo>=</m:mo> <m:mn>0.010</m:mn> </m:math> ) scores was negatively correlated with preoperative BFMDRS-M score. In the metaregression analysis, the best predictive model showed that preoperative BFMDRS-M, disease duration ( <o:math xmlns:o="http://www.w3.org/1998/Math/MathML" id="M8"> <o:mi>p</o:mi> <o:mo>=</o:mo> <o:mn>0.047</o:mn> </o:math> ), and the age at symptom onset ( <q:math xmlns:q="http://www.w3.org/1998/Math/MathML" id="M9"> <q:mi>p</q:mi> <q:mo>=</q:mo> <q:mn>0.027</q:mn> </q:math> ) were important. Conclusion. Patients with early-onset dystonia have a significant effect after GPi-DBS treatment, and DYT-1 (+) and DYT-11 (+) patients are better candidates for GPi-DBS. Lower preoperative score, later age of onset, and an earlier age at surgery probably predict better clinical outcomes.