Neurology 2018 07 29;91(5):e463-e471. Epub 2018 Jun 29.
From the Departments of Neurology (M.L.H., M.T., L.E.H., A.L.M., A.D.C., T.L.D., F.T.P., P.H., D.C.) and Neurosurgery (P.E.K.), Vanderbilt University Medical Center, Nashville, TN; Department of Neurology (M.R.D.), Emory University School of Medicine, Atlanta, GA; Laboratory of Molecular Immunology (L.E.H.), National Institute of Allergy and Infectious Diseases, Bethesda, MD; Movement Disorders and Neuromodulation Center (J.L.O.), Department of Neurology, University of California San Francisco; Department of Neurology (K.R.C.), Walter Reed National Military Center, Bethesda; and Department of Epidemiology (L.T.D., A.L.S., D.M.S., J.T.), Johns Hopkins University, Baltimore, MD.
Objective: To evaluate whether the progression of individual motor features was influenced by early deep brain stimulation (DBS), a post hoc analysis of Unified Parkinson's Disease Rating Scale-III (UPDRS-III) score (after a 7-day washout) was conducted from the 2-year DBS in early Parkinson disease (PD) pilot trial dataset.
Methods: The prospective pilot trial enrolled patients with PD aged 50-75 years, treated with PD medications for 6 months-4 years, and no history of dyskinesia or other motor fluctuations, who were randomized to receive optimal drug therapy (ODT) or DBS plus ODT (DBS + ODT). At baseline and 6, 12, 18, and 24 months, all patients stopped all PD therapy for 1 week (medication and stimulation, if applicable). UPDRS-III "off" item scores were compared between the ODT and DBS + ODT groups (n = 28); items with significant between-group differences were analyzed further.
Results: UPDRS-III "off" rest tremor score change from baseline to 24 months was worse in patients receiving ODT vs DBS + ODT ( = 0.002). Rest tremor slopes from baseline to 24 months favored DBS + ODT both "off" and "on" therapy ( < 0.001, = 0.003, respectively). More ODT patients developed new rest tremor in previously unaffected limbs than those receiving DBS + ODT ( = 0.001).
Conclusions: These results suggest the possibility that DBS in early PD may slow rest tremor progression. Future investigation in a larger cohort is needed, and these findings will be tested in the Food and Drug Administration-approved, phase III, pivotal, multicenter clinical trial evaluating DBS in early PD.
Classification Of Evidence: This study provides Class II evidence that for patients with early PD, DBS may slow the progression of rest tremor.