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

Abstract

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.

A durable gain in motor and non-motor symptoms of Parkinson’s Disease following repeated caloric vestibular stimulation: A single-case study

“…It is, however, difficult to believe that an improvement of this origin would still be evident at both formal assessment and from relativesÕ testimony 5months later. In line with previous study (Samoudi et al, 2012(Samoudi et al, , 2015, we therefore tentatively attribute the effects to a vestibular-based mechanism.…”

“…In a recent hemi-parkinsonian rat study, artificial stimulation of the vestibular nerves via transmastodial galvanic current was associated with improved locomotory ability and allied increases in GABA concentration in substantia nigra pars reticulata (Samoudi, Nissbrandt, Dutia & Bergquist, 2012). In human PD studies, galvanic vestibular stimulation has been shown to spontaneously reduce postural sway (Pal, Rosengren & Colebatch, 2009), postural response time (Samoudi, JivegOErd, Mulavara, & Bergquist, 2015) and also lead to a quickening of bradykinesic rest-to-active transitions in the wrist and trunk (Pan, Soma, Yamamoto, 2008). Although these results demonstrate the potential therapeutic value of vestibular stimulation in PD, they were acquired under highly prescribed, controlled laboratory conditions, utilized a narrow range of mostly experimental rather than clinical outcomes, and perhaps most importantly did not show if the effects persisted beyond a few hours.…”

Impacto da doença de Parkinson na performance do equilíbrio em diferentes demandas atencionais

“…Most studies found in the literature evaluate balance with patients in orthostatism and with feet positioned in parallel [19][20][21][22][23] . Previous studies suggest that simpler stances, such as two-feet position, present low difficulty demand for maintaining balance 24 .…”

Noise-Enhanced Vestibular Input Improves Dynamic Walking Stability in Healthy Subjects

“…Previous studies examining the effect stochastic resonance for the vestibular system have considered behavioral tasks, i.e. quiet standing, in which the baseline vestibular inputs were below vestibular detection thresholds [9,10,16]. To test whether subthreshold vestibular input is also present during locomotion at different velocities, we measured and analyzed head kinematics for each walking trial.…”

“…The electrical signal consisted of zero-mean Gaussian white noise within a frequency range of 0-30 Hz [9,16]. The GVS intensity (i.e., peak amplitude) was set to 80% of cutaneous threshold, which has been previously shown to be the optimal amplitude of noisy GVS in healthy subjects [9].…”