Jaan Nandwani1, Joan Miravite2, Winona Tse1, Matthew Swan1, Naomi Lubarr3, Brian Kopell1, Joohi Jimenez-Shahed1
1Icahn School of Medicine at Mount Sinai, 2Mount Sinai Beth Israel, 3Mount Sinai Beth Israel Medical Center
Objective:
This study aims to explore factors that may contribute to the effectiveness of DBS in the treatment of dystonia.
Background:
Deep brain stimulation (DBS) effectively treats movement disorders when other
therapeutics become less effective in managing symptoms, but there can be heterogeneity of response based on several factors.
Design/Methods:
Demographic, genetic, and programming data from dystonia patients who underwent DBS at Mount Sinai Hospital (2011-2022) was collected through IRB-approved retrospective chart review when pre- and post- clinical rating scales were available. Patients were categorized based on post-DBS improvement [partial (<50% change) vs good (≥50%) change in BFMDRS or TWSTRS scores]. Total electrical energy delivered (TEED) was calculated using therapeutic impedance values or assumed to be 1000Ω when unavailable. Chi-squared, unpaired t-tests, Pearson’s correlation and ANOVA were performed to compare groups.
Results:
N=17 patients with bilateral GPi DBS were included, 52.3% female, 76.5% >18 years (mean = 35.1 ± 18.1) and 70.6% Caucasian. Medications were significantly reduced after DBS (p<0.05). N=12 had a good and n=5 had partial improvement. All patients with DYT-1 dystonia (n=6) experienced good improvement. Disease duration at time of surgery correlated poorly with improvement (r=0.28 NS). There was no significant difference in TEED per hemisphere between the good and partial improvement groups (p=0.45). N=21 hemispheres were treated with high PW/low Freq, and the odds ratio of association with a good response was 1.11. N=6 hemispheres had high Freq/low PW paradigms, used significantly lower TEED, and all had a good response. Hemispheres with high PW/high Freq (n=7) used significantly higher TEED (p<0.001) with n=3 good and n=4 partial improvement.
Conclusions:
Variation in dystonia DBS outcomes in a heterogeneous cohort do not appear to be strictly dependent on disease duration, genetics, or TEED. Programming paradigms may be important and could indicate proximity to relevant circuitry and/or circuit characteristics, which may individually vary.