Acute and Long Term Effects of VNS on Memory in Patients With Refractory Epilepsy

May 2, 2023 updated by: University Hospital, Ghent

Research on the Acute and Long Term Effects on Memory and the Mechanism of Action of Vagus Nerve Stimulation in Patients With Refractory Epilepsy

Refractory epilepsy patients implanted with a vagus nerve stimulator perform a memory test at baseline in three conditions: invasive vagus nerve stimulation (VNS), transcutaneous vagus nerve stimulation (taVNS) and sham stimulation. After 6 weeks of VNS treatment, the memory test is repeated in two condition: invasive vagus nerve stimulation (VNS) and sham stimulation.

The endpoint of this experiment is assessing the effect of VNS and taVNS on memory performance.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

Previous studies underlined the potential of both invasive as transcutaneous auricular vagus nerve stimulation to ameliorate certain cognitive functions.

In this randomized, controlled cross-over within-subjects study, a memory test is conducted in patients with refractory epilepsy who are implanted with a vagus nerve stimulation.

The memory test consists out of a word recognition paradigm based on the study of Clarck et al. published in 1999 in Nature Neuroscience. Testing is performed at baseline (before start of the stimulation) and after 6 weeks of treatment with vagus nerve stimulation.

During the first session, the patients complete the word recognition task during three interventions:

  • Invasive vagus nerve stimulation
  • Transcutaneous vagus nerve stimulation (cymba concha)
  • Sham vagus nerve stimulation (no stimulation)

During the second session, the patients complete the word recognition task during two interventions:

  • Invasive vagus nerve stimulation
  • Sham vagus nerve stimulation (no stimulation)

The goal is to investigate if invasive vagus nerve stimulation and transcutaneous nerve stimulation can influence (i.e. improve) the performance on the memory task and if this performance is improved after 6 weeks of VNS treatment.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
16

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Belgium
      • Ghent, Belgium, 9000
        • University Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Refractory epilepsy
  • Treated with vagus nerve stimulation
  • IQ >= 70 and able to perform the memory task

Exclusion Criteria:

  • IQ < 70

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Vagus nerve stimulation
Invasive vagus nerve stimulation
Diagnostic test: Memory task
Word recognition task
Experimental: Transcutaneous vagus nerve stimulation
Cymba concha stimulation
Diagnostic test: Memory task
Word recognition task
Sham Comparator: Sham vagus nerve stimulation
No vagus nerve stimulation
Diagnostic test: Memory task
Word recognition task

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Immediate recall score at session 1
Time Frame: At baseline
Free recall score for correctly recalled words (min score 0,max score 21, higher score indicates better performance), calculated as a percentage
At baseline
Immediate recall score at session 2
Time Frame: After 6 weeks of VNS treatment
Free recall score for correctly recalled words (min score 0, max score 21, higher score indicates better performance)), calculated as a percentage
After 6 weeks of VNS treatment
Delayed recognition scores at session 1
Time Frame: At baseline
Hitscore for correctly recognized target words (min score 0,max score 63, higher score indicates better performance), score for not recognized target words= misses (min score 0,max score 63, higher score indicates worse performance),correct rejection score of non-target related words (min score 0,max score 63, higher score indicates better performance), score for incorrect recognition of non-target related words= false alarms (min score 0,max score 63, higher score indicates worse performance), discrimination index= hit score -false alarm score (min score 0,max score 63, higher score indicates better performance). All scores are calculated as a percentage.
At baseline
Delayed recognition scores at session 2
Time Frame: After 6 weeks of VNS treatment
Hitscore for correctly recognized target words (min score 0,max score 48, higher score indicates better performance), score for not recognized target words= misses (min score 0,max score 48, higher score indicates worse performance),correct rejection score of non-target related words (min score 0,max score 48, higher score indicates better performance), score for incorrect recognition of non-target related words= false alarms (min score 0,max score 48, higher score indicates worse performance), discrimination index= hit score -false alarm score (min score 0,max score 48, higher score indicates better performance). All scores are calculated as a percentage.
After 6 weeks of VNS treatment

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Attention score at session 1
Time Frame: At baseline
Score of correct responses on 6 open question (min score 0, max score 6, higher score indicates better performance), calculated as a percentage
At baseline
Attention score at session 2
Time Frame: After 6 weeks of VNS treatment
Score of correct responses on 6 open question (min score 0, max score 6, higher score indicates better performance), calculated as a percentage
After 6 weeks of VNS treatment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University Hospital, Ghent

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
November 22, 2018

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
August 28, 2020

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
August 28, 2020

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
August 19, 2021

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 26, 2021

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
September 1, 2021

Study Record Updates

Last Update Posted (Estimate)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
May 4, 2023

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 2, 2023

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
May 1, 2023

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • EC/2016/0786

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

UNDECIDED

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Refractory Epilepsy

Clinical Trials on Memory task

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

Cookie Settings

We use cookies to ensure that we give you the best experience on our website. For more details carefully read our Privacy and Cookies Policy. ...>>>You can change your preferences or withdraw your consent at any time by deleting the cookies from your website or computer as described in the policy. Please accept it and choose your preferences by ticking the corresponding boxes in the "Manage Settings" section below. Please carefully read our Terms of Service before you proceed with using any part of this website.
«Manage Settings