Physiopathology of Lower Cortical Activation in COPD Patients: Contribution of Cortical Neuromodulation

Physiology Clinical Trial

Official title:

Physiopathology of Lower Cortical Activation in COPD Patients: Contribution of Cortical Neuromodulation

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT03368703
• Other study ID #: 5S_EXCCOM
• Status: Completed
• Phase: N/A
• Start date: June 1, 2017
• Est. completion date: June 30, 2018

Study information

• Verified date: January 2020
• Source: 5 Santé
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

Patients with COPD have lower cortical activation and higher cortical inhibitory levels. The purpose of this study is to test the reversibility the lower cortical activation by counterbalancing the increased cortical inhibitory levels with neuro-modulation.

Description:

Chronic obstructive pulmonary disease (COPD) patients exhibit not only respiratory symptoms but also a peripheral muscular weakness. This weakness is characterized by a loss in strength, harmful for the patients' life quality and vital prognostic. Even if many papers have enlightened damages at a peripheral level, the muscular atrophy itself cannot totally explain the loss in force. Furthermore, the contractile properties of COPD muscles fibres are preserved. Consequently, it seems that the peripheral muscle weakness cannot only be explained by peripheral factors and central structures may be involved.

A recent work showed that during quadriceps voluntary contraction, cortical activation in COPD patients was significantly lower than in healthy subjects, contributing in the loss in strength. However, the pathophysiology underlying this loss of strength is still unclear and two hypotheses can be advanced: 1) the influence of anatomical lesions in the brain of COPD patients and 2) the particular metabolism of this population. Indeed, COPD patients show a reduced oxidative activity and an increased glycolytic contribution (decreased type I fibres and increased type II fibres, increased glycolytic enzymes activity, increased metabolites production). This specific metabolic may lead to an over-activation of type III-IV afferents, projecting onto somatosensory cortex sensitive to metabolites at a peripheral level, and produce inhibitory activity on the primary motor cortex, seat of the motor control. What is reported in the literature so far, is that COPD patients display increased cortical inhibitory values than healthy subjects.

Therefore, beyond understanding better the nervous mechanisms involved in the COPD's peripheral muscle weakness, the aim of this study is to counterbalance this increased cortical inhibitory level.

We hypothesize that modulating inhibitory processes at a cortical level would induced a reduction of inhibitions in patients with COPD and an increase in the force produced. In case this hypothesis would be verified, we will be able to confirm that this increased cortical level in COPD patients is reversible and may be a target for rehabilitation.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 34
• Est. completion date: June 30, 2018
• Est. primary completion date: June 30, 2018
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 45 Years to 75 Years

Eligibility

Inclusion Criteria:

• Health insurance

• Patients : COPD Gold II-IV

• Patients : No rehabilitation since at least 1 yrs

• Control : sedentary (< 9 Voorips)

Exclusion Criteria:

• Pregnant women

• Seizures

• Unable to give written consent

• Metalic object above shoulders

• Dermatological issue concerning surface electrodes

• Drugs influencing central nervous system

• Caffeine consumption > 4 coffee / day

• Neurological disorders

• Patients : recent exacerbation (< 4 weeks)

Related Conditions & MeSH terms

• Physiology

Intervention

Device:
• Anodal transcranial direct-current-stimulation
2mA / 20min Anodal and Sham tDCS over dominant M1. Anodal tDCS consists of 30s of ramp up followed by 20min of stimulation and 30s of ramp down.
• Sham transcranial direct-current-stimulation
Sham tDCS consists of only 30s of ramp up followed by 30s of ramp down and no further stimulation. Participants therefore have the same feeling for both modalities : slight itching due to the induced current at the beginning of the protocol (during around 30s) allowing no differentiation by the participant between the anodal or sham sessions.

Locations

Country	Name	City	State
France	Cliniques du Souffle	Lodeve	Herault

Sponsors (1)

Lead Sponsor	Collaborator
5 Santé

Country where clinical trial is conducted

France, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in motor-evoked potentials	Cortical excitability	Baseline (pre-intervention) ; Post-Stim (immediately post-intervention) ; Post-30 (30min post-intervention)
Secondary	Change in short-interval intracortical inhibition	Cortical inhibition level	Baseline (pre-intervention) ; Post-Stim (immediately post-intervention) ; Post-30 (30min post-intervention)
Secondary	Change in cortical silent period	Cortical inhibition level	Baseline (pre-intervention) ; Post-Stim (immediately post-intervention) ; Post-30 (30min post-intervention)
Secondary	Change in cortical voluntary activation	Motor command	Baseline (pre-intervention) ; Post-Stim (immediately post-intervention) ; Post-30 (30min post-intervention)
Secondary	Change in strength	Functional output	Baseline (pre-intervention) ; Post-Stim (immediately post-intervention) ; Post-30 (30min post-intervention)