Cardiac-coherence breathing training for adults with Long COVID in Réunion

Randomized Controlled Trial Evaluating the Effectiveness of a Breathing Control Technique on Long COVID Symptoms at the Reunion University Hospital

This project will test whether a simple breathing-control method (cardiac coherence) helps adults in Réunion with Long COVID reduce symptoms and improve daily functioning.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 200 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Centre Hospitalier Universitaire de la Réunion (other)
• Locations: 2 sites (Saint-Denis and 1 other locations)
• Trial ID: NCT05851859 on ClinicalTrials.gov

What this trial studies

Adults living in Réunion who meet the WHO definition of Long COVID and can document prior SARS‑CoV‑2 infection with a negative antigen test will be enrolled at CHU de la Réunion (Saint‑Denis and Saint‑Pierre). Participants will receive structured training in a cardiac coherence breathing technique (guided slow breathing to improve heart‑rate variability) as the interventional program. Symptom scores and functional outcomes will be recorded over time to measure change after the breathing program, with predefined exclusions for respiratory comorbidity, recent breathing‑technique practice, certain cardiac medications or devices, pregnancy, cognitive impairment, or guardianship. The intervention is non‑pharmacologic and delivered in an outpatient hospital setting.

Who should consider this trial

Good fit: Adults (18+) living in Réunion with a WHO‑defined diagnosis of Long COVID and a documented prior SARS‑CoV‑2 infection who test antigen‑negative at inclusion are ideal candidates.

Not a fit: Patients with chronic or disabling respiratory disease that prevents respiratory training, those already practicing similar breathing techniques within the last six months, or people taking excluded cardiac or psychoactive medications are unlikely to benefit from this program.

Why it matters

Potential benefit: If effective, the breathing technique could reduce symptom burden and improve daily functioning and quality of life for people with Long COVID.

How similar studies have performed: Breathing‑retraining and heart‑rate‑variability techniques have shown some symptom and quality‑of‑life improvements in other post‑viral and long‑COVID cohorts, but results across studies are limited and mixed.

Eligibility criteria

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

Where this trial is running

Saint-Denis and 1 other locations

• CHU de la Réunion — Saint-Denis, France (RECRUITING)
• CHU de la Réunion — Saint-Pierre, France (NOT_YET_RECRUITING)

Study contacts

• Study coordinator: Léa BRUNEAU

Conditions: Long COVID