Patients treated with deep brain stimulation for dystonia may experience long-term improvements in quality of life that persist an average of 10 or more years post-surgery, with a low prevalence of cognitive impairment and stimulation-induced parkinsonism, according to a study published in Movement Disorders.
The objectives of this cohort study were to examine quality of life outcomes in individuals with dystonia treated with deep brain stimulation and to determine the potential long-term cognitive impact and the incidence of stimulation-induced parkinsonism. Researchers contacted 54 potential participants via social media, 37 of whom agreed to participate in the study (16 women; average age, 39.7±16.6; n=23 with a mutation in the DYT1 gene). The average time post-implantation was 10.5 years. Primary outcomes were scores on: the Telephone Montreal Cognitive Assessment, the parkinsonian symptoms questionnaire, the Measurement of Every Day Cognition, and a Short Form survey.
The participants’ average Telephone Montreal Cognitive Assessment score was 20.1±1.6, with 10.3% of scores within the impaired range (ie, score <18). The mean self-reported parkinsonian symptom score was 13.8±14.7, with hypophonia and worsening balance being the most common symptoms. The average Measurement of Every Day Cognition score was 1.25±0.35 with 10.3% of study participants scoring in the impaired range (ie, score >1.81). The Short Form survey scores showed an average improvement from 43.7 before deep brain stimulation to 69.5 in current daily life (P <.0005).
Improvements in all areas of life were recorded in patients treated with deep brain stimulation, improvements which were sustained for more than a decade. “[Patients] with dystonia and DBS in our population appeared to experience few parkinsonian symptoms, which may be related to age at surgery. Objective and subjective measures of cognition showed that long-term cognitive impairment after DBS is uncommon in this population,” concluded the study authors.
Hogg E, During E, Tan EE, et al. Sustained quality-of-life improvements over 10 years after deep brain stimulation for dystonia. Mov Disord. 2018 Jul; 33(7):1160-1167. doi: 10.1002/mds.27426.