Short pulses in neurostimulation for Parkinson's Disease - SPIN-PD

Background: Subthalamic nucleus deep brain stimulation (STN-DBS) is a well-established treatment for patients with Parkinson’s disease. Previous acute challenge studies suggested that short pulse widths might increase the therapeutic window while maintaining motor symptom control with a decrease in energy consumption. However, only little is known about the effect of short pulse width stimulation beyond the setting of an acute challenge. Objective: To compare 4 weeks of STN-DBS with conventional pulse width stimulation (60 µs) to 4 weeks of STN-DBS with short pulse width stimulation (30 µs) regarding motor symptom control. Methods: This study was a monocentric, double-blinded, randomized crossover non-inferiority trial investigating whether short pulse width stimulation with 30 µs maintains equal motor control as conventional 60 µs stimulation over a period of 4 weeks (German Clinical Trials Register No. DRKS00017528). Primary outcome was the difference in motor symptom control as assessed by a motor diary. Secondary outcomes included energy consumption measures, non-motor effects, side-effects, and quality of life. Results: Due to a high dropout rate, the calculated sample size of 27 patients was not met and 24 patients with Parkinson’s disease and STN-DBS were included in the final analysis. However, there were no differences in any investigated outcome parameter between the two treatment conditions. Conclusion: This study demonstrates that short pulse width settings (30 µs) provide non-inferior motor symptom control as conventional (60 µs) stimulation without significant differences in energy consumption. Future studies are warranted to evaluate a potential benefit of short pulse width settings in patients with pronounced dyskinesia.