HALOA: Cardiac Coherence With CPAP for Obstructive Sleep Apnea (HALOA)

Effect of Adding Cardiac Coherence to Continuous Positive Airway Pressure in Patients With Obstructive Sleep Apnea: A Multicenter Randomized Delayed-Start Controlled Study

This multicenter study will evaluate whether adding cardiac coherence breathing sessions to continuous positive airway pressure (CPAP) improves sleep quality in adults with newly diagnosed obstructive sleep apnea who are starting CPAP. Approximately 180 participants will be randomly assigned to one of two groups. Both groups will start treatment with the HALOA CPAP system. In one group, the cardiac coherence module will be activated at the start of treatment. In the other group, participants will use CPAP alone for 8 weeks before the module is activated.

Sleep quality will be assessed at study entry, at 8 weeks, and at 16 weeks using the Pittsburgh Sleep Quality Index. The primary comparison will assess the change in sleep quality from study entry to week 8 between the two groups. Secondary assessments will include daytime sleepiness, insomnia symptoms, anxiety and depression symptoms, treatment satisfaction, usability of the cardiac coherence module, CPAP use, and heart-rate variability when polysomnography recordings are available.

Study Overview

• Status: Not yet recruiting
• Conditions: OSA; Obstructive Sleep Apnea (OSA)
• Intervention / Treatment: Device: HALOA Continuous Positive Airway Pressure (CPAP); Behavioral: Cardiac Coherence Breathing Module

Detailed Description

Obstructive sleep apnea is commonly treated with continuous positive airway pressure (CPAP). However, some patients have difficulty adhering to CPAP or experience persistent sleep-related symptoms. Cardiac coherence is a guided breathing practice intended to support relaxation and emotional regulation. The HALOA system combines CPAP treatment with a cardiac coherence module. This study will assess whether access to this module from the start of CPAP treatment improves subjective sleep quality compared with starting the module after an initial period of CPAP alone.

This is a prospective, multicenter, randomized, open-label, delayed-start controlled study. Approximately 180 adults with newly diagnosed obstructive sleep apnea and an indication for CPAP will be enrolled at 11 planned centers. Participants will be randomly assigned in equal numbers to one of two groups.

All participants will begin CPAP treatment using the HALOA system and will receive usual CPAP care. Participants in the immediate-intervention group will have the cardiac coherence module activated at study entry and will receive guidance on its use. Participants in the delayed-intervention group will use CPAP without cardiac coherence for the first 8 weeks. After the week 8 assessment, the module will be activated and participants will receive guidance on its use.

Study assessments will take place at baseline, week 8, and week 16. The primary outcome is the change in the global Pittsburgh Sleep Quality Index (PSQI) score from baseline to week 8, comparing the two randomized groups. The week 8 assessment provides the controlled comparison before participants in the delayed-intervention group begin cardiac coherence. Changes in PSQI from week 8 to week 16 in the delayed-intervention group will also be assessed to explore the effect after the module is introduced.

Secondary assessments will include daytime sleepiness using the Epworth Sleepiness Scale, insomnia symptoms using the Insomnia Severity Index, and anxiety and depression symptoms using the Hospital Anxiety and Depression Scale. Patient satisfaction will be assessed using the CSQ-8 and a study-specific questionnaire. Usability of the cardiac coherence module will be assessed using the System Usability Scale. CPAP adherence will be evaluated using device data, including hours of use and the proportion of participants meeting the protocol-defined adherence threshold. Heart-rate variability indices will be evaluated from polysomnography recordings when available.

Participants will be adults with obstructive sleep apnea diagnosed by polysomnography within the 3 months before inclusion and for whom CPAP treatment is indicated. The protocol lists recent CPAP or mandibular advancement device treatment, refusal of or contraindication to CPAP, inability to use the cardiac coherence device, and specified medical, psychiatric, or other circumstances among the non-inclusion criteria.

• Study Type: Interventional
• Enrollment (Estimated): 180
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: François FB Bughin, Md, PhD; Phone Number: 0033761783081; Email: fbughin@hotmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age 18 years or older.
• Obstructive sleep apnea diagnosed according to ICSD-3 criteria by polysomnography performed within 3 months before study inclusion.
• Indication for CPAP treatment according to current recommendations: apnea-hypopnea index (AHI) ≥30 events/hour, or AHI ≥15 events/hour with severe cardiovascular or respiratory comorbidity.
• Written informed consent.

Exclusion Criteria:

• CPAP or mandibular advancement device treatment within the 3 months before inclusion.
• Refusal of CPAP treatment.
• Contraindication to CPAP treatment.
• Unstable psychiatric disorder or substance-use disorder.
• Technical inability to use the cardiac coherence device.
• Not affiliated with, or not a beneficiary of, a social security system.
• Deprivation of liberty by judicial or administrative decision.
• Legal protective measure, including guardianship or curatorship.
• Pregnancy, childbirth, or breastfeeding.
• Language barrier preventing participation.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Immediate cardiac coherence with CPAP; Participants will start HALOA CPAP at study inclusion. The cardiac coherence breathing module will be activated from the start of treatment, with guidance on its use. Participants will be assessed at baseline, week 8, and week 16.	Device: HALOA Continuous Positive Airway Pressure (CPAP); CPAP treatment using the HALOA system, initiated at study inclusion in both groups and provided as part of usual care.; Behavioral: Cardiac Coherence Breathing Module; Guided cardiac coherence breathing sessions using the module integrated with the HALOA system. The module is activated at study inclusion in the experimental group and after the week 8 assessment in the active comparator group.
Active Comparator: Delayed cardiac coherence with CPAP; Participants will start HALOA CPAP at study inclusion and use it without the cardiac coherence module for 8 weeks. After the week 8 assessment, the module will be activated and guidance on its use provided. Participants will be assessed at baseline, week 8, and week 16.	Device: HALOA Continuous Positive Airway Pressure (CPAP); CPAP treatment using the HALOA system, initiated at study inclusion in both groups and provided as part of usual care.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Global Pittsburgh Sleep Quality Index (PSQI) Score	Absolute change in the global PSQI score from baseline (V1) to week 8 (V2), comparing the randomized groups. PSQI scores range from 0 to 21; higher scores indicate poorer sleep quality.	Baseline to week 8

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in PSQI Score After Delayed Initiation of Cardiac Coherence	Absolute change in global PSQI score from week 8 (V2) to week 16 (V3) in the delayed-intervention group, after the cardiac coherence module is activated.	Week 8 to week 16
Change in Daytime Sleepiness	Changes in Epworth Sleepiness Scale (ESS)	Baseline, week 8, and week 16
Change in insomnia symptoms	Changes in Insomnia Severity Index (ISI)	Baseline, week 8, and week 16
Change in depression symptoms	Changes in Hospital Anxiety and Depression Scale anxiety and depression subscale scores (HADS-A and HADS-D).	Baseline, week 8, and week 16
Patient Satisfaction	Patient satisfaction measured using the Client Satisfaction Questionnaire (CSQ-8) and the study-specific S-HALOA-CC questionnaire. S-HALOA-CC results will be considered exploratory.	Baseline, week 8, and week 16, as applicable
Usability of the Cardiac Coherence Module	Usability measured using the System Usability Scale (SUS) after exposure to the cardiac coherence module.	Week 8 for the immediate-intervention group and week 16 for the delayed-intervention group
CPAP Adherence	Mean nightly CPAP use and the proportion of participants meeting the protocol-defined adherence threshold of at least 4 hours per night on at least 70% of nights.	At weeks 8 and 16; device use assessed over the 7-day and 30-day periods before each visit
Heart-Rate Variability	Changes in time-domain and frequency-domain heart-rate variability indices derived from polysomnography recordings, when follow-up recordings are available.	Baseline and week 16, when recordings are available
Clinically Meaningful Improvement in Sleep Quality	Proportion of participants with a decrease of at least 3 points in global PSQI score over the specified assessment interval.	Baseline to week 8, week 8 to week 16, and baseline to week 16

Collaborators and Investigators

• Sponsor: Clinique du Millenaire

Publications and helpful links

General Publications

• Herhaus B, Kalin A, Gouveris H, Petrowski K. Mobile Heart Rate Variability Biofeedback Improves Autonomic Activation and Subjective Sleep Quality of Healthy Adults - A Pilot Study. Front Physiol. 2022 Feb 17;13:821741. doi: 10.3389/fphys.2022.821741. eCollection 2022.
• Laborde S, Hosang T, Mosley E, Dosseville F. Influence of a 30-Day Slow-Paced Breathing Intervention Compared to Social Media Use on Subjective Sleep Quality and Cardiac Vagal Activity. J Clin Med. 2019 Feb 6;8(2):193. doi: 10.3390/jcm8020193.
• Stepnowsky C, Zamora T, Edwards C. Does Positive Airway Pressure Therapy Result in Improved Sleep Quality? Health (Irvine Calif). 2014 Oct;6(18):2416-2424. doi: 10.4236/health.2014.618278.

Study record dates

Study Major Dates

• Study Start (Estimated): November 1, 2026
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): December 1, 2028

Study Registration Dates

• First Submitted: November 5, 2026
• First Submitted That Met QC Criteria: November 5, 2026
• First Posted (Actual): November 10, 2026

Study Record Updates

• Last Update Posted (Actual): November 10, 2026
• Last Update Submitted That Met QC Criteria: November 5, 2026
• Last Verified: November 1, 2026

More Information

Terms related to this study

• Keywords: Obstructive Sleep Apnea; CPAP; Sleep quality; heart rate variability; Treatment adherence; cardiac coherence
• Additional Relevant MeSH Terms: Nervous System Diseases; Mental Disorders; Respiratory Tract Diseases; Respiration Disorders; Sleep Wake Disorders; Apnea; Sleep Disorders, Intrinsic; Dyssomnias; Sleep Apnea Syndromes; Behavior; Health Behavior; Sleep Apnea, Obstructive; Sleep Initiation and Maintenance Disorders; Treatment Adherence and Compliance
• Other Study ID Numbers: 26.01725.000477

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

IPD Plan Description

The sponsor has not yet determined whether individual participant data and the corresponding data dictionary will be made available to other researchers. The plan will be updated once a decision has been made.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No