Trial Outcomes & Findings for Can Transcranial Direct Current Stimulation Improve Ambulation and Fatigue Resistance in People With MS? (NCT NCT02987621)

Results Overview

Knee extensor strength will be tested with tDCS (less than 10V) and sham stimulation (0V). Participants performed maximal voluntary contractions (MVCs) with the knee extensors to objectively determine the weaker leg as more-affected, which was afterwards confirmed by the subject's self-report and used for the subsequent endurance task. This task consisted of a sustained isometric contraction at 15% MVC until volitional task termination and was immediately followed by a post MVC. During tDCS, stimulation intensity was ramped up to 2 mA, started 90 second prior to the task, and extended until task failure or a maximum stimulation length of 20 minutes. For Sham, the current was ramped up to 2 mA, but turned off after 30 seconds.

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

14 participants

Primary outcome timeframe

At session 1 and minimum of 7 days later

Results posted on

2020-07-30

Participant Flow

Participant milestones

Participant milestones
Measure	Sham First, Seven Day Wash Out, Then tDCS Separated by a minimum of 7 days, participants will perform leg muscle strength and fatigue testing once with tDCS and once with Sham in a counterbalanced order. Leg muscle strength testing will be measured by performing a series of maximal effort knee extension, knee flexion, plantar/dorsi-flexion trials. Note: the 6 minute walk test was not conducted. The fatigue testing will be measured by time to fatigue with isometric contraction of the knee extensors. tDCS: Less than 10V of Transcranial Direct Current Stimulation Sham tDCS: Sham 0V of Transcranial Direct Current Stimulation	tDCS First, 7 Day Wash Out, Then Sham Separated by a minimum of 7 days, participants will perform leg muscle strength and fatigue testing once with tDCS and once with Sham in a counterbalanced order. Leg muscle strength testing will be measured by performing a series of maximal effort knee extension, knee flexion, plantar/dorsi-flexion trials. Note: the 6 minute walk test was not conducted. The fatigue testing will be measured by time to fatigue with isometric contraction of the knee extensors. tDCS: Less than 10V of Transcranial Direct Current Stimulation Sham tDCS: Sham 0V of Transcranial Direct Current Stimulation
Overall Study STARTED	7	7
Overall Study COMPLETED	7	7
Overall Study NOT COMPLETED	0	0

Reasons for withdrawal

Withdrawal data not reported

Baseline Characteristics

Race and Ethnicity were not collected from any participant.

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure	All Study Participants n=14 Participants Separated by a minimum of 7 days, participants will perform leg muscle strength and fatigue testing once with tDCS and once with Sham in a counterbalanced order. Leg muscle strength testing will be measured by performing a series of maximal effort knee extension, knee flexion, plantar/dorsi-flexion trials. Note: the 6 minute walk test was not conducted. The fatigue testing will be measured by time to fatigue with isometric contraction of the knee extensors. tDCS: Less than 10V of Transcranial Direct Current Stimulation Sham tDCS: Sham 0V of Transcranial Direct Current Stimulation
Age, Categorical <=18 years	0 Participants n=14 Participants
Age, Categorical Between 18 and 65 years	12 Participants n=14 Participants
Age, Categorical >=65 years	2 Participants n=14 Participants
Sex: Female, Male Female	11 Participants n=14 Participants
Sex: Female, Male Male	3 Participants n=14 Participants

PRIMARY outcome

Timeframe: At session 1 and minimum of 7 days later

Population: Crossover design

Knee extensor strength will be tested with tDCS (less than 10V) and sham stimulation (0V). Participants performed maximal voluntary contractions (MVCs) with the knee extensors to objectively determine the weaker leg as more-affected, which was afterwards confirmed by the subject's self-report and used for the subsequent endurance task. This task consisted of a sustained isometric contraction at 15% MVC until volitional task termination and was immediately followed by a post MVC. During tDCS, stimulation intensity was ramped up to 2 mA, started 90 second prior to the task, and extended until task failure or a maximum stimulation length of 20 minutes. For Sham, the current was ramped up to 2 mA, but turned off after 30 seconds.

Outcome measures

Outcome measures
Measure	All Study Participants n=14 Participants Participants will perform leg muscle strength testing with tDCS. On a separate day they will repeat the leg muscle strength testing with Sham stimulation. Leg strength testing will be measured by performing a series of maximal effort knee extension, knee flexion, plantar/dorsi-flexion trials. Furthermore, participants perform a 6 minute walk. tDCS: Less than 10V of Transcranial Direct Current Stimulation Sham tDCS: Sham 0V of Transcranial Direct Current Stimulation
Leg Muscle Strength With and Without tDCS. Sham Stimulation	330 Newtons Standard Error 98
Leg Muscle Strength With and Without tDCS. tDCS Stimulation	323 Newtons Standard Error 15

PRIMARY outcome

Timeframe: At session 1 and minimum of 7 days later.

Population: Crossover design

Knee extensor endurance (fatigue) will be tested with tDCS (less than 10V) and sham stimulation (0V), as reported as time to failure. During tDCS, stimulation intensity was ramped up to 2 mA, started 90 second prior to the task, and extended until task failure or a maximum stimulation length of 20 minutes. For Sham, the current was ramped up to 2 mA, but turned off after 30 seconds.

Outcome measures

Outcome measures
Measure	All Study Participants n=14 Participants Participants will perform leg muscle strength testing with tDCS. On a separate day they will repeat the leg muscle strength testing with Sham stimulation. Leg strength testing will be measured by performing a series of maximal effort knee extension, knee flexion, plantar/dorsi-flexion trials. Furthermore, participants perform a 6 minute walk. tDCS: Less than 10V of Transcranial Direct Current Stimulation Sham tDCS: Sham 0V of Transcranial Direct Current Stimulation
Leg Muscle Endurance With and Without tDCS. tDCS Stimulation	1087 seconds Standard Error 938
Leg Muscle Endurance With and Without tDCS. Sham Stimulation	872 seconds Standard Error 547

PRIMARY outcome

Timeframe: At session 1 and minimum of 7 days later

Population: No data was collected

After completion of the tDCS/Sham strength assessment participants will perform a 6 minute walk test. The test will be performed in a cordoned off hallway with 2 cones placed 30 meters apart. Once the participants begin walking, a timer will be started and the distance covered every min will be recorded. Participants are allowed to stop and rest during the test if required. Every minute during the walk test participants will be asked their rating of perceived exertion (RPE, 0-10 scale).

Outcome measures

Outcome data not reported

Adverse Events

All Study Participants-Leg Muscle Strength tDCS

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

All Study Participants-Leg Muscle Strength Sham

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

All Study Participants-Leg Muscle Endurance tDCS

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

All Study Participants-Leg Muscle Endurance Sham

Serious events: 0 serious events

Other events: 0 other events

Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Manager of Research Operations

Colorado State University

Phone: 9704912242

Email: [email protected]

Results disclosure agreements

Principal investigator is a sponsor employee
Publication restrictions are in place