Evaluation of the Effectiveness of Breathing Control Technique on Long COVID Symptoms at the Reunion University Hospital Cardiac Coherence and Long COVID Symptoms

Study Overview
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Brief Summary
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Despite the controversy, on October 6, 2021, the World Health Organization (WHO) recognized Long Coronavirus disease (COVID) by officially defining it:  symptoms appeared 3 months after the onset of the primary infection by the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), persisting for at least 2 months and which cannot be explained by any other condition . Long COVID can affects any type of patient and has polymorphic and fluctuating symptoms over time. The Reunion Island is a French overseas department located in the Indian Ocean accounting more than 860,000 inhabitants. It has recorded since March 11, 2020, nearly 491,825 cases of COVID-19 and 961 deaths of hospitalized patients. Reunion's population is multi-ethnic and younger than the metropolitan France's one. It also has a higher prevalence of obesity and type 2 diabetes, two serious form factors of COVID-19. This specific context makes this island a particular study site for Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) and Long COVID. In addition, some studies have confirmed the involvement of the autonomic nervous system (ANS) in the symptomatology of Long COVID and demonstrated that patients with a Long COVID present a dysfunction of their ANS which is objectified by a reduced Heart Rate Variability (HRV). The regulation of heart rate by the ANS is strongly favored by respiration. A regular slow and deep breathing training helps to adjust the baroreflex, which connect heart rate, breathing and blood pressure. The result of this training is an induced state called cardiac coherence (CC). The investigator therefore hypothesize that respiratory training to CC could re-educate the ANS and durably improve the symptomatology of patients with Long COVID.

Official Title
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Evaluation of the Effectiveness of Breathing Control Technique on Long COVID Symptoms at the Reunion University Hospital Cardiac Coherence and Long COVID Symptoms

Conditions
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Long COVID

Intervention / Treatment
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* Other: Cardiac coherence


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients over the age of 18, living in Reunion and having a diagnosis of Long COVID according to the World Health Organization (WHO) definition will be included in this study. These patients must attest to their primary infection with Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) and present a negative antigen test at the time of inclusion. Exclusion Criteria: Patients: with a chronic or disabling respiratory pathology preventing respiratory training (asthma, Chronic Obstructive Pulmonary Disease (COPD), active tuberculosis, pulmonary sequelae of COVID-19, etc.) practicing or having practiced a regular respiratory control technique (yoga, Cardiac coherence training, etc.) in the last 6 months taking a beta-blocker, betamimetic, anti-arrhythmic, morphine, antidepressant treatment (Escitalopram) having a pacemaker or severe heart disease Current and known pregnancy or breastfeeding woman with a cognitive deficit under guardianship/curators or under judicial protection

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Complementary respiratory training to cardiac coherence (CC)<br>The  intervention  group will benefit from a complementary respiratory training to CC during 6 months in addition to the usual care procedure. | Other: Cardiac coherence<br>* Use of Cardiac coherence (complementary respiratory training) during 6 month<br>|
| No Intervention: Usual care procedure in the event of Long COVID<br>The  control  group will follow a usual care procedure in the event of Long COVID | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of the effectiveness of a respiratory training to cardiac coherence on the reduction in the symptomatology of patients with Long COVID. | mean score on the Long COVID Symptom Tool (ST) scale Score 0 to 53 / Higher score mean worse outcome | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Evaluation of the effectiveness of a respiratory training to cardiac coherence on the decrease of overall symptoms over time | Long COVID Symptom Tool (ST) scale Score 0 to 53 / Higher score mean worse outcome | T0, 1 month, 2 months, 3 months, 6 months | 
| Evaluation of the effectiveness of a respiratory training to cardiac coherence on the decrease of specifics symptoms : fatigue | The 11-item Chalder Fatigue Scale (CFS-11) score 0 to 11 / Higher score mean worse outcome | 3 months, 6 months | 
| Evaluation of the effectiveness of a respiratory training to cardiac coherence on the decrease of specifics symptoms : dyspnoea | Modified Medical Research Council (MMRC) dyspnoea scale score 0 to 5 / Higher score mean worse outcome | 3 months, 6 months | 
| Evaluation of the effectiveness of a respiratory training to cardiac coherence on the decrease of specifics symptoms : Anxiety and Depression | Hospital Anxiety and Depression scale (HADS) Score 0 to 42 / Higher score mean worse outcome | 3 months, 6 months | 
| Evaluation of the effectiveness of a respiratory training to cardiac coherence on the decrease of specifics symptoms : cognitive disorders | Montreal Cognitive Assessment (MoCA) Score 0 to 30 / Higher score mean better outcome | 3 months, 6 months | 
| Evaluation of the effectiveness of a respiratory training to cardiac coherence on the decrease of specifics symptoms : Post Traumatic Stress Disorder | Posttraumatic Stress Disorder Checklist for Diagnostic and statistical manual of mental disorders, version 5 (PCL-5) Score 0 to 80 / Higher score mean worse outcome | 3 months, 6 months | 
| Evaluation of the effectiveness of a respiratory training to CC on the impact of the disease on daily life | Long COVID Impact Tool (IT) scale Score 0 to 60 / Higher score mean worse outcome | T0, 1 month, 2 months, 3 months, 6 months |