Skip to content

Effect of Non-invasive Vagus Nerve Stimulation on Cerebrovascular Reactivity and Cognition in Chronic Stroke Patients

Effect of Non-invasive Vagus Nerve Stimulation on Cerebrovascular Reactivity and Cognition in Chronic Stroke Patients

Status
Not yet recruiting
Phases
Unknown
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT07626242
Enrollment
40
Registered
2026-06-04
Start date
2026-06-01
Completion date
2027-02-28
Last updated
2026-06-04

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Stroke

Brief summary

This study will be conducted to assess the effect of non-invasive vagus nerve stimulation on cerebrovascular reactivity and cognition in chronic stroke patients

Detailed description

Stroke is a leading cause of disability worldwide, resulting in physical, cognitive, and emotional impairments. These impairments significantly affect individuals, families, and communities. It imposes a substantial social and financial burden on healthcare systems and economies. Deficits in cognitive functions are highly associated with reduced treatment outcomes after stroke. This interferes with social and occupational recovery and limit psychosocial functioning. Introducing new therapeutic methods such as non-invasive vagus nerve stimulation (VNS) alongside traditional rehabilitation is essential for enhancing cognitive function after stroke. Vagus nerve stimulation can be invasive or non-invasive. Non-invasive method of VNS via transcutaneous stimulation of the peripheral auricular branch of the Vagus nerve (taVNS) is safer, better-tolerated method for delivering VNS with the same effect of invasive VNS. There are few key human studies that assessed the effects of transcutaneous vagus nerve stimulation (tVNS) on cerebrovascular reactivity (CVR) and cognition in chronic stroke patients. Up to our knowledge, this is the first Egyptian study that will assess the effect of transcutaneous vagus nerve stimulation on cerebrovascular reactivity and cognition in chronic stroke patients. This study will hopefully be of benefit in the physical therapy field. This may guide rehabilitation programs of physical therapy toward better results.

Interventions

Transcutaneous vagal nerve stimulation will be done through EME Therapic 9200 electrotherapy device (EME Physio, Via degli Abeti 88/161122 Pesaro (PU), Italy). A clip electrode will be applied on cymba conchae of left ear. Stimulation parameters will be set to 30 minutes treatment time, a pulse width of 300 microseconds, pulse frequency 30 HZ and a pulsed mode with a duty cycle of 50% (30 sec on and 30 sec off time).

DEVICESham trans-auricular vagus nerve stimulation

Patients will receive false trans-auricular vagus nerve stimulation through EME Therapic 9200 electrotherapy device (EME Physio, Via degli Abeti 88/161122 Pesaro (PU), Italy). The ear clip electrode will be attached to the center of the left earlobe of the patient, as it is free from vagus innervation. Stimulation parameters will be set to 30 minutes treatment time, a pulse width of 300 microseconds, pulse frequency 30 HZ and a pulsed mode with a duty cycle of 50% (30 sec on and 30 sec off time).

OTHERConventional physical therapy

The physical therapy program will include strengthening exercises to the antispastic muscles, stretching exercises to spastic muscles, gait training exercises, proprioceptive neuromuscular facilitation exercises for upper limb and lower limb, and graduated balance exercise.

DEVICEComputer based cognitive rehabilitation training

* RehaCom (Dr. G. Schuhfrted Ges.m.b.II., model No. A-2340 device) will be used in this study for assessment and training two cognitive domains: attention/concentration and figural memory. Each patient will be in a comfortable sitting position in front of a screen during the session. The two domains will be assessed at the end of each session. * Attention/concentration domain (AC) includes 24 levels of difficulty. Assessment will start at level one and will be advanced to more challenging levels. * Figural memory domain includes nine levels of difficulty. Assessment will start at level one and will be advanced to more challenging levels. Each cognitive training session will last 30 minutes, with 15 minutes dedicated to each targeted domain.

Sponsors

Cairo University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
50 Years to 60 Years
Healthy volunteers
No

Inclusion criteria

* Forty chronic ischemic hemiparetic patients, of both sexes, will represent the sample. * The patient's age will range from 50 to 60 years old. * Duration of illness will range from six months to twelve months. * Patients with mild cognitive impairment according to Montreal Cognitive Assessment (MoCA) scale (from 18 to 25). * Spasticity will be 1 or 1+ according to Modified Aschworth scale. * Educated patients.

Exclusion criteria

* The patients will be excluded if they have one of the followings: * Patients with other neurological disease that affect cognition. * Visual, verbal or hearing impairments that can interfere with communication. * Depression assessed by Hamilton Depression Scale (Ham-D). * Patients with poor bone window. * History of psychiatric disease. * Hemorrhagic stroke patients. * Uncontrolled blood pressure or low heart rate. * Uncontrolled diabetes (\>130 mg/dL especially if consistently over 150 to 160 mg/dL) * Patients with any taVNS contraindications (open heart surgery, pacemaker or other implants, previous surgical intervention on Vagus nerve, Facial or ear pain, and recent ear trauma) * Stroke patients with severe cognitive impairment. * Uncooperative patients.

Design outcomes

Primary

MeasureTime frameDescription
Breathing holding index4 weeksTranscranial doppler ultrasonography technique will be used to assess cerebrovascular reactivity by measuring the percentage increase in cerebral blood flow velocity during apnea, divided by the duration of breath hold in seconds. Breath holding index will be calculated according to the following equation: BHI= ((Mean Flow Velocity (MFV) post- Mean Flow Velocity (MFV)rest/ Mean Flow Velocity (MFV)rest) × (100/Duration in second)) normal range:1.03-1.65.

Secondary

MeasureTime frameDescription
Montreal Cognitive Assessment Scale (MOCA):4 weeksIt will be used to assess cognition before and after treatment period for all patients. Each patient will be asked to write and draw using the non-affected hand. The test consists of a single page, with reading items presented in a clear and appropriately sized font. The assessment will include short-term memory, executive functions, visuospatial abilities, language, attention, concentration, working memory, and temporal and spatial orientation. Total score of MoCA is from 0 to 30. From 26-30 is normal cognition, from 18-25 is mild cognitive impairment (MCI), from 10-17 is moderate cognitive impairment, and less than ten is Severe cognitive impairment.
Attention/concentration domain (AC)4 weeksRehaCom (Dr. G. Schuhfrted Ges.m.b.II., model No. A-2340 device) will be used in this study to assess and rehabilitate the cognitive function in stroke patients. It is a valid and reliable instrument for assessing and improving cognitive functions in stroke patients. Attention/concentration domain (AC) includes 24 levels of difficulty. Assessment will start at level one and will be advanced to more challenging levels. normal range :10-12 level; indicative cognitive impairment: below 10 level
Figural memory domain4 weeksRehaCom (Dr. G. Schuhfrted Ges.m.b.II., model No. A-2340 device) will be used in this study to assess and rehabilitate the cognitive function in stroke patients. It is a valid and reliable instrument for assessing and improving cognitive functions in stroke patients. Figural memory domain includes 9 levels of difficulty. Assessment will start at level one and will be advanced to more challenging levels. normal range :7-8 level; indicative cognitive impairment: below 7 level

Countries

Egypt

Contacts

CONTACTAhmed Kamal
kamsafahm567@gmaol.com01110053571
CONTACTMarwa Abd El-Moneim, PHD
marwa.mostafa@cu.edu.eg01005661591
STUDY_DIRECTORMohamed Soliman, Professor

Cairo University

STUDY_DIRECTORShimaa Mohamed, Professor

Cairo University

STUDY_CHAIRMoshera Darwish, Professor

Cairo University

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Jun 5, 2026