Effects of Stochastic Vestibular Galvanic Stimulation and LDOPA on Balance and Motor Symptoms in Patients With Parkinson's Disease

Background: Balance problems contribute to reduced quality of life in Parkinson's disease (PD) and available treatments are often insufficient for treating axial and postural motor symptoms. Objective: To investigate the safety of use and possible effects of stochastic vestibular stimulation (SVS) alone and combined with LDOPA in patients with PD. Methods: SVS or sham stimulation was administered to 10 PD patients in a double-blind placebo controlled cross-over pilot study. Motor symptoms and balance were evaluated in a defined off-medication state and after a 200 mg test dose of LDOPA, using UPDRS-III, Posturo-Locomotor-Manual (PLM) movement times (MT), static posturography and force plate measurements of the correcting response to a balance perturbation. Results: Patients did not detect when SVS was active, but SVS increased nausea after LDOPA in two patients. Mixed model analysis demonstrated that SVS improved balance corrections after a backward perturbation and shortened the postural response time. In static posturography there was significant interaction between effects of SVS, medication and proprioceptive input (standing on foam vs. on hard support) and SVS decreased the total sway-path with eyes closed and off medication. As expected, LDOPA improved the UPDRS-III scores and MT. There was an interaction between the effect of SVS and LDOPA on UPDRS-III partly because of reduced UPDRS-III scores with SVS in the off-medication state. Conclusions: Short term use of SVS is safe, improves corrective postural responses and may have a small positive effect on motor symptoms in PD patients off treatment. (C) 2015 The Authors. Published by Elsevier Inc.