Supplementary Material for: Quality of Life after Deep Brain Stimulation: A primary versus secondary dystonia comparative study

Introduction. Generalized dystonia is a motor disorder causing major limitations in daily living activities. Deep brain stimulation (DBS) is an established therapy for primary disorders, but its efficacy in secondary ones remains variable. Although quality of life (QoL) assessment is crucial in disabling conditions to understand the comprehensive impact of surgical treatment on daily life, the available questionnaires are not well adapted. Methods. Herein, QoL after DBS was evaluated using a “homemade” scale. The DBS-QoL scale is a new questionnaire specifically designed for generalized dystonia patients. Results. Twenty-one DYT1 patients and 40 cerebral palsy patients underwent GPi-DBS during the inclusion period. Clinical improvement was measured using the BFMDRS and compared to QoL evolution using the DBS-QoL. We identified a significant positive impact of DBS on motor and functional aspects for both groups, with superior gains in DYT1 patients. In this group, we found significant improvement in functional aspects, whereas in perinatal hypoxic patients, the opposite trend was reported, with better satisfaction in terms of wellbeing. Across both etiologies, patients expressed satisfaction with the surgical outcomes (83%). Conclusion. QoL assessment, using a dedicated scale, was shown to complement BFMDRS, enhancing the detection of subtle symptom improvements in DBS-treated patients.