The role of genetics in the treatment of dystonia with deep brain stimulation: Systematic review and Meta-analysis.

BACKGROUND: Dystonia is a movement disorder characterized by sustained or intermittent muscle contractions that lead to involuntary postures or repetitive movements. Genetic mutations are being increasingly recognized as a cause of dystonia. Deep brain stimulation (DBS) is one of the limited treatment options available. However, there are varying reports on its efficacy in genetic dystonias. This systematic review of the characteristics of genetic dystonias treated with DBS and their outcomes aims to aid in the evaluation of eligibility for such treatment. METHODS: We performed a PUBMED search of all papers related to genetic dystonias and DBS up until April 2022. In addition to performing a systematic review, we also performed a meta-analysis to assess the role of the mutation on DBS response. We included cases that had a confirmed genetic mutation and DBS along with pre-and post-operative BFMDRS. RESULTS: Ninety-one reports met our inclusion criteria and from them, 235 cases were analyzed. Based on our analysis DYT-TOR1A dystonia had the best evidence for DBS response and Rapid-Onset Dystonia Parkinsonism was among the least responsive to DBS. CONCLUSION: While our report supports the role of genetics in DBS selection and response, it is limited by the rarity of the individual genetic conditions, the reliance on case reports and case series, and the limited ability to obtain genetic testing on a large scale in real-time as opposed to retrospectively as in many cases.

Impact of fatigue in Parkinson's disease: the Fatigue Impact Scale for Daily Use (D-FIS).

The Fatigue Impact Scale for Daily Use (D-FIS) was used in a cross-sectional study including 142 consecutive Parkinson's disease (PD) patients. Usual clinical measures for PD, the Montgomery-Asberg Depression Rating Scale and the Parkinson's Disease Questionnaire-8 items were applied. In addition to the D-FIS, patients with fatigue (67.6%, PWF) completed the Multidimensional Fatigue Inventory (MFI), a visual analogue scale for fatigue (VAS-F) and a Global Perception of Fatigue scale (GPF). Relevant psychometric D-FIS results were: floor effect = 4.2%; ceiling effect = 1.1%; skewness = 0.44; item homogeneity = 0.63; Cronbach's alpha = 0.93; item-total correlation = 0.68 (item 1)-0.82 (item 8); standard error of measurement = 2.15; convergent validity with other fatigue measures = 0.54 [GPF]-0.62 [VAS-F] (p<0.001). In a multiple linear regression model, fatigue, depression, and disability independently influenced HRQoL, as measured by the PDQ-8. Patients on amantadine had lower prevalence of fatigue. In PD, D-FIS is a consistent and valid measure for fatigue, a frequent symptom previously found to impair patients' HRQoL. Fatigue was also linked to depression and disability in this study.