Clinical Trial Details
— Status: Completed
Administrative data
NCT number |
NCT04046055 |
Other study ID # |
201906759 |
Secondary ID |
|
Status |
Completed |
Phase |
N/A
|
First received |
|
Last updated |
|
Start date |
December 1, 2019 |
Est. completion date |
April 1, 2020 |
Study information
Verified date |
October 2022 |
Source |
University of Iowa |
Contact |
n/a |
Is FDA regulated |
No |
Health authority |
|
Study type |
Interventional
|
Clinical Trial Summary
Parkinson's disease (PD) is the second most common neurodegenerative disorder and affects
approximately 1 million people in the United States with total annual costs approaching 11
billion dollars. The most common symptoms of PD are tremor, stiffness, slowness, and trouble
with balance/walking, which lead to severe impairments in performing activities of daily
living. Current medical and surgical treatments for PD are either only mildly effective,
expensive, or associated with a variety of side-effects. Therefore, the development of
practical and effective add-ons to current therapeutic treatment approaches would have many
benefits. Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation
technique that can affect brain activity and can help make long-term brain changes to improve
functions like walking and balance. While a few initial research studies and review articles
involving tDCS have concluded that tDCS may improve PD walking and balance, many results are
not meaningful in real life and several crucial issues still prevent tDCS from being a useful
add-on intervention in PD. These include the selection of stimulation sites (brain regions
stimulated) and tDCS electrode placement. Most studies have targeted the motor cortex (brain
region that controls intentional movement), but there is evidence that the cerebellum - which
helps control gait and balance, is connected to several other brain areas, and is easily
stimulated with tDCS - may be a likely location to further optimize walking and balance in
PD. There is also evidence that certain electrodes placements may be better than others.
Thus, the purpose of this study is to determine the effects of cerebellar tDCS stimulation
using two different placement strategies on walking and balance in PD.
Additionally, although many tDCS devices are capable of a range of stimulation intensities
(for example, 0 mA - 5 mA), the intensities currently used in most tDCS research are less
than 2 mA, which is sufficient to produce measurable improvements; but, these improvements
may be expanded at higher intensities. In the beginning, when the safety of tDCS was still
being established for human subjects, careful and moderate stimulation approaches were
warranted. However, recent work using stimulation at higher intensities (for example, up to 4
mA) have been performed in different people and were found to have no additional negative
side-effects. Now that the safety of tDCS at higher intensities is better established,
studies exploring the differences in performance between moderate (i.e., 2 mA) and higher
(i.e., 4 mA) intensities are necessary to determine if increasing the intensity increases the
effectiveness of the desired outcome.
Prospective participants will include 10 people with mild-moderate PD that will be recruited
to complete five randomly-ordered stimulation sessions, separated by at least 5 days each.
Each session will involve one visit to the Integrative Neurophysiology Laboratory (INPL) and
will last for approximately one hour. Data collection is expected to take 4-6 months. Each
session will include walking and balance testing performed while wearing the tDCS device.
Total tDCS stimulation time for each session will be 25 minutes.
Description:
Parkinson's disease (PD) is the second most common neurodegenerative disorder and affects
approximately 1 million people in the United States with total annual costs approaching 11
billion dollars. The most common symptoms of PD are tremor, stiffness, slowness, and trouble
with balance/walking, which lead to severe impairments in performing activities of daily
living. Current medical and surgical treatments for PD are either only mildly effective,
expensive, or associated with a variety of side-effects. Therefore, the development of
practical and effective add-ons to current therapeutic treatment approaches would have many
benefits. Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation
technique that can affect brain activity and can help make long-term brain changes to improve
functions like walking and balance. While a few initial research studies and review articles
involving tDCS have concluded that tDCS may improve PD walking and balance, many results are
not meaningful in real life and several crucial issues still prevent tDCS from being a useful
add-on intervention in PD. These include the selection of stimulation sites (brain regions
stimulated) and tDCS electrode placement. Most studies have targeted the motor cortex (brain
region that controls intentional movement), but there is evidence that the cerebellum - which
helps control gait and balance, is connected to several other brain areas, and is easily
stimulated with tDCS - may be a likely location to further optimize walking and balance in
PD. There is also evidence that certain electrodes placements may be better than others.
Thus, the purpose of this study is to determine the effects of cerebellar tDCS stimulation
using two different placement strategies on walking and balance in PD.
Additionally, although many tDCS devices are capable of a range of stimulation intensities
(for example, 0 mA - 5 mA), the intensities currently used in most tDCS research are less
than 2 mA, which is sufficient to produce measurable improvements; but, these improvements
may be expanded at higher intensities. In the beginning, when the safety of tDCS was still
being established for human subjects, careful and moderate stimulation approaches were
warranted. However, recent work using stimulation at higher intensities (for example, up to 4
mA) have been performed in different people and were found to have no additional negative
side-effects. Now that the safety of tDCS at higher intensities is better established,
studies exploring the differences in performance between moderate (i.e., 2 mA) and higher
(i.e., 4 mA) intensities are necessary to determine if increasing the intensity increases the
effectiveness of the desired outcome.
Prospective participants will include 10 people with mild-moderate PD that will be recruited
to complete five randomly-ordered stimulation sessions (baseline/SHAM, unilateral tDCS
montage at 2 mA, unilateral tDCS montage at 4 mA, bilateral tDCS montage at 2 mA, and
bilateral montage at 4 mA), separated by at least 5 days. Each session will involve one visit
to the Integrative Neurophysiology Laboratory (INPL) and will last for approximately one
hour. Data collection is expected to take 4-6 months. Each session will include gait
(30-meter walk test [30mWT], 6-minute walk test [6MWT], Timed Up and Go [TUG]) and balance
testing (standing on a force platform with either a firm surface or a foam surface) performed
in conjunction with one of the five randomly-ordered stimulation conditions (SHAM, unilateral
2 mA, unilateral 4 mA, bilateral 2 mA, and bilateral 4 mA). Total tDCS stimulation time for
each session will be 25 minutes. Gait characteristics (i.e., gait speed, stride length, step
length, toe-off angle, etc.) and distance walked during the 30mWT and 6MWT will also be
determined with inertial sensors (OPAL motion sensors).