Cervical dystonia patients with psychiatric classification: Despite dystonia improvement less improvement in other domains after DBS surgery

<h2>Abstract</h2><h3>Background</h3> Patient satisfaction of deep brain stimulation (DBS) for cervical dystonia (CD) is heterogeneous. A high prevalence of psychiatric disorders in patients with CD is well-established. The presence of psychiatric classification in CD may affect the outcomes of DBS treatment. <h3>Methods</h3> A cohort of 49 patients with CD and GPi-DBS was retrospectively studied in two centers. Psychiatric history was obtained from patient records. Pre- and post-operative Toronto Western Spasmodic Torticollis Rating Scores (TWSTRS, range 0–85) were compared between patients with and those without psychiatric classification. The TWSTRS disability and pain sub-scores were combined to evaluate non-motor improvement. The severity sub-score was used to assess motor improvement. <h3>Results</h3> Twenty (40.8 %) patients had a psychiatric classification, predominantly major depressive disorder and anxiety disorders. Following DBS treatment, the overall mean (± SD) improvement on the TWSTRS was 38.0 ± 29.2 %. Significantly, patients with a psychiatric classification experienced less improvement in the non-motor domain than the patients without a psychiatric classification (29.1 ± SD 38.2 % [range −41.7 to 96.6 %] vs. 51.9 ± 33.6 % [range −8.6 to 100.0 %]; <i>p</i> = 0.02). <h3>Conclusion</h3> Our findings indicate that CD patients with psychiatric classifications experience less non-motor improvement following DBS. Psychiatric comorbidities could influence the lacking experience of successful DBS treatment despite good motor outcome. Therefore, it is important to establish these comorbidities in CD patients undergoing DBS with respect to expectation management and treatment if necessary.