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Parkinson DiseaseNCT03180515

Neural and Kinematic Features of Freezing of Gait for Adaptive Neurostimulation

A study testing Activa PC+S Neurostimulator in people with Parkinson Disease, run by Stanford University at 1 site in United States.

Completed

Finished. The study has ended and is not enrolling. Results may be posted on the official record.

Official record
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Trial summary

Continuous deep brain stimulation (cDBS) is an established therapy for the major motor signs in Parkinson's disease, however some patients find that it does not adequately treat their freezing of gait (FOG). Read more about this study

Who is it for?
Ages 18 to 80 years
Conditions the study is for
Parkinson Disease
What is being tested?
Activa PC+S Neurostimulator
Type of treatment
Medical device
Could I receive a placebo?
No, everyone receives an active treatment
How many people
12 participants
Where
1 siteUnited States
Study dates
15 May 2017to 31 Oct 2018
Phase
Interventional
Are there results?
Yes, posted in the registrySummary in the doctors' view

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 18 to 80 years
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • A diagnosis of idiopathic Parkinson's disease, with bilateral symptoms at Hoehn and Yahr Stage greater than or equal to II.
  • Documented improvement in motor signs on versus off dopaminergic medication, with a change in the Unified Parkinson's Disease Rating Scale motor (UPDRS III) score of >= 30% off to on medication.
  • The presence of complications of medication such as wearing off signs,fluctuating responses and/or dyskinesias, and/or medication refractory tremor,and/or impairment in the quality of life on or off medication due to these factors.
  • Subjects should be on stable doses of medications, which should remain unchanged until the DBS system is activated. After the DBS system is optimized(during which time the overall medication dose may be reduced to avoid discomfort and complications such as dyskinesias) the medication dose should remain unchanged, if possible, for the duration of the study.
  • Treatment with carbidopa/levodopa, and with a dopamine agonist at the maximal tolerated doses as determined by a movement disorders neurologist.
  • Ability and willingness to return for study visits, at the initial programming and after three, six and twelve months of DBS.
  • Age > 18
  • Has a history of and/or displays freezing of gait

Who cannot join

  • Subjects with significant cognitive impairment and/or dementia as determined bya standardized neuropsychological battery.
  • Subjects with clinically active depression, defined according to the Diagnostic and Statistical manual of Mental Disorders, Fourth Edition (DSM-IV) criteria and as scored on a validated depression assessment scale.
  • Subjects with very advanced Parkinson's disease, Hoehn and Yahr stage 5 on medication (non-ambulatory).
  • Age > 80.
  • Subjects with an implanted electronic device such as a neurostimulator, cardiac pacemaker/defibrillator or medication pump.
  • Subjects, who are pregnant, are capable of becoming pregnant, or who are breast feeding.
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  • Patients with cortical atrophy out of proportion to age or focal brain lesions that could indicate a non-idiopathic movement disorder as determined by MRI
  • Subjects having a major comorbidity increasing the risk of surgery (prior stroke,severe hypertension, severe diabetes, or need for chronic anti-coagulation other than aspirin).
  • Subjects having any prior intracranial surgery.
  • Subjects with a history of seizures.
  • Subjects, who are immunocompromised.
  • Subjects with an active infection.
  • Subjects, who require diathermy, electroconvulsive therapy (ECT), or transcranial magnetic stimulation (TMS) to treat a chronic condition.
  • Subjects, who have an inability to comply with study follow-up visits or study protocol.
  • Subjects, who are unable to understand or sign the informed consent.

Trial locations and contacts

1 site in 1 country.

United States1 site

  • Stanford Movement Disorders

    Palo Alto, California, 94304

Other trials in United States

About this study

Continuous deep brain stimulation (cDBS) is an established therapy for the major motor signs in Parkinson's disease, however some patients find that it does not adequately treat their freezing of gait (FOG). Currently, cDBS is limited to "open-loop" stimulation,without real-time adjustment to the patient's state of activity, fluctuations and types of motor symptoms, medication dosages, or neural markers of the disease. The purpose of this study is to determine if an adaptive DBS system,responding to patient specific, clinically relevant neural or kinematic feedback related to FOG, is more effective than continuous DBS on the motor Unified Parkinson's Disease Rating Scale (UPDRS III) and gait measures of PD.

Being tested
Activa PC+S Neurostimulator
Medical subject headings
Parkinson Disease

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Activa PC+S NeurostimulatorDevice

    Also called adaptive deep brain stimulation (aDBS), continuous deep brain stimulation (cDBS)

    Activa PC+S Neurostimulator is approved for both aDBS and cDBS paradigms.

Study groups in NCT03180515
Study groupRoleWhat they receive
Activa PC+S NeurostimulatorExperimentalAll patients will complete motor testing on both continuous DBS and adaptive DBS during a study visit. The UPDRS rater and the patient will be blind to which type of stimulation they are on.
Receives: Device: Activa PC+S Neurostimulator

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Incidence of Treatment-Emergent Adverse Events [Safety and Tolerability] Related to aDBS

    Safety, tolerability and feasibility of aDBS

    Measured: 30 min - 2 hours

Secondary outcomes (9)

  1. Aim 1: Alpha Power

    Subthalamic nucleus (STN) local field potentials (LFP) recordings demonstrate oscillatory neuronal activity in both the alpha (8-12 Hz) and beta (13-30 Hz) bands in the resting state in PD. Spectrograms were generated using a short-time Fourier transform, with a 1 second Hanning window and a 0.5 second overlap, creating a frequency resolution of 1 Hz. Power spectral densities were calculated using the Welch method with the same window and overlap parameters. Power was summed in the beta and alpha bands. This power can be representative of the magnitude of oscillatory activity in this frequency band occurring in this brain region.

    Measured: 30 minutes

  2. Aim 1: Beta Power

    Subthalamic nucleus (STN) local field potentials (LFP) recordings demonstrate oscillatory neuronal activity in both the alpha (8-12 Hz) and beta (13-30 Hz) bands in the resting state in PD. Spectrograms were generated using a short-time Fourier transform, with a 1 second Hanning window and a 0.5 second overlap, creating a frequency resolution of 1 Hz. Power spectral densities were calculated using the Welch method with the same window and overlap parameters. Power was summed in the beta and alpha bands. This power can be representative of the magnitude of oscillatory activity in this frequency band occurring in this brain region.

    Measured: 30 minutes

  3. Aim 1: Alpha Sample Entropy

    The predictability of the local field potentials (band-pass filtered between 8-12 Hz for alpha) was analyzed using Sample Entropy (SampEn), a nonlinear measure suitable for physiological time series. SampEn may be a more consistent measure and more suitable to shorter time series data than approximate entropy, partially due to the elimination of counting self matches. SampEn is calculated as the negative logarithm of the estimated conditional probability that if consecutive subseries of length m are similar according to some preset tolerance r, the consecutive subseries of length m+1 will be similar too. Here the length of the vector pairs, m, denotes the embedding dimension.

    Measured: 30 minutes

  4. Aim 1: Beta Sample Entropy

    The predictability of the local field potentials (band-pass filtered between 15-30 Hz for beta) was analyzed using Sample Entropy (SampEn), a nonlinear measure suitable for physiological time series. SampEn may be a more consistent measure and more suitable to shorter time series data than approximate entropy, partially due to the elimination of counting self matches. SampEn is calculated as the negative logarithm of the estimated conditional probability that if consecutive subseries of length m are similar according to some preset tolerance r, the consecutive subseries of length m+1 will be similar too. Here the length of the vector pairs, m, denotes the embedding dimension.

    Measured: 30 minutes

  5. Aim 2: Asymmetry

    Asymmetry during both forward walking and stepping in place was calculated using periods of walking or stepping when the subject was not freezing. According to previous studies, asymmetry is defined as: 100*(absolute value of the natural log of the shorter average swing time over the longer average swing time) or mathematically: 100*| ln (SSWT/LSWT) |

    where SSWT = shorter mean swing time LSWT = longer mean swing time

    Measured: 30 minutes

  6. Aim 2: Arrhythmicity

    Arrhythmicity during both forward walking and stepping in place was calculated using periods of walking or stepping when the subject was not freezing. According to previous studies, arrhythmicity is defined as the mean stride time coefficient of variation of both legs, and a greater stride time CV implies less rhythmic gait or stepping. Higher arrhythmicity corresponds to more arrhythmic, or more impaired, gait.

    Measured: 30 minutes

  7. Aim 2: Stride Time

    Kinematic Features associated with Freezing of Gait

    Measured: 30 minutes

  8. Aim 2: Percent Time Freezing

    Freezing of gait episodes during stepping in place were identified using a validated computerized algorithm, and during forward walking by a blinded rater. The percent time freezing was calculated by dividing the time spent freezing by the total time to complete the task then multiplying by 100 to get a percent. If no freezing was observed, then the percent time freezing reported was 0.0%.

    Measured: 30 minutes

  9. Percent Time Freezing

    Freezing of gait episodes during stepping in place were identified using a validated computerized algorithm. The percent time freezing was calculated by dividing the time spent freezing by the total time to complete the task then multiplying by 100 to get a percent. If no freezing was observed, then the percent time freezing reported was 0.0%. The percent time spent freezing was compared while the participant was doing the stepping in place task on continuous deep brain stimulation (cDBS) and while the participant was doing the stepping in place task on adaptive deep brain stimulation (aDBS).

    Measured: 30 minutes

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted8 Jun 2017
  2. Study start15 May 2017
  3. Primary completion31 Oct 2018
  4. Study completion31 Oct 2018

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase N/A
Primary purpose
Basic science
Allocation
Not applicable
Intervention model
Single group
Masking
None (open label)
Enrolment
12 participants (actual)
IDs, dates and publications
ClinicalTrials.gov ID
NCT03180515
Sponsor's protocol ID
1R21NS096398
Status last verified
Nov 2019
First submitted
6 Jun 2017
Last updated
21 Nov 2019
Data monitoring committee
Yes
FDA-regulated drug
No
FDA-regulated device
Yes
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

A study testing Activa PC+S Neurostimulator in people with Parkinson Disease, run by Stanford University at 1 site in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 8 inclusion and 15 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: finished, as of the sponsor's last update on 21 Nov 2019. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

Are results available for this study?

Yes. Results are posted in the registry (first posted 4 Nov 2019). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.

How can a doctor refer a patient or contact the research team?

The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Incidence of Treatment-Emergent Adverse Events [Safety and Tolerability] Related to aDBS (time frame: 30 min - 2 hours). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT03180515.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 21 Nov 2019.

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