Promoting Emotional and Autonomic Control Through Guided Breathing Exercises for Emerging Adults With Autism

NCT07238153 | Recruiting

• 1 other identifier: S70725
• Study Type: interventional
• Target: 68
• Locations: 1 country
• Sites: 2

Brief Summary

This study examines the impact of guided breathing exercises on stress and heart rate variability (HRV) in autistic young adults. It explores how daily movement behavior (sleep, physical activity and sedentary behavior) influences HRV and to what extent two guided breathing exercises can affect HRV. Additionally, the study investigates how participants perceive the exercises in terms of usability and usefulness.

Conditions

Autism; Autism Spectrum Disorder

Keywords

Heart rate variability; Stress; Biofeedback; Autism; Movement behavior; Guided breathing exercise; slow paced breathing

Outcome Measures

Primary Outcomes (2)

• Change in cardiac vagal modulation of heart rate based on resting-state HRV.

  Calculated as (1) a time domain measure (RMSSD: Root Mean Square of Successive Differences). Three-lead electrocardiographic data will be captured using the NeXus-10 MKII biofeedback device and Biotrace+ Software (MindMedia B.V., The Netherlands). Disposable, self-adhesive and pre-gelled electrodes (Kendall™ ECG Electrodes Arbo™ H124SG, Covidien, Ireland) will be used without specific skin preparations at a sampling rate of 256 SPS. For the recording of the breathing frequency, an elastic band with stretch-sensitive sensors and a sampling rate of 32 SPS is placed around the waist.

  At all assessment points: at the start of the study (week 0, time point 0) before the intervention (week 5, time point 1) + after 5 weeks of intervention (week 10, time point 2) + after 5 weeks at the follow-up (week 15, time point 3)

• Change in cardiac vagal modulation of heart rate based on resting-state HRV

  Calculated as (2) a frequency domain measures (HF-HRV). Three-lead electrocardiographic data will be captured using the NeXus-10 MKII biofeedback device and Biotrace+ Software (MindMedia B.V., The Netherlands). Disposable, self-adhesive and pre-gelled electrodes (Kendall™ ECG Electrodes Arbo™ H124SG, Covidien, Ireland) will be used without specific skin preparations at a sampling rate of 256 SPS. For the recording of the breathing frequency, an elastic band with stretch-sensitive sensors and a sampling rate of 32 SPS is placed around the waist.

  At all assessment points: at the start of the study (week 0, time point 0) before the intervention (week 5, time point 1) + after 5 weeks of intervention (week 10, time point 2) + after 5 weeks at the follow-up (week 15, time point 3)

Secondary Outcomes (10)

• Change in mental health indicators

  At all assessment points: at the start of the study (week 0, time point 0) before the intervention (week 5, time point 1) + after 5 weeks of intervention (week 10, time point 2) + after 5 weeks at the follow-up (week 15, time point 3)

• Change in mental health indicators

  At all assessment points: at the start of the study (week 0, time point 0) before the intervention (week 5, time point 1) + after 5 weeks of intervention (week 10, time point 2) + after 5 weeks at the follow-up (week 15, time point 3)

• Change in mental health indicators

  At all assessment points: at the start of the study (week 0, time point 0) before the intervention (week 5, time point 1) + after 5 weeks of intervention (week 10, time point 2) + after 5 weeks at the follow-up (week 15, time point 3)

• feasibility and acceptability of the HRV-BF and SPB interventions.

  For 5 weeks 4 times per day (before and after each sessions) during the intervention phase (between week 5 and week 10)

• feasibility and acceptability of the HRV-BF and SPB interventions.

  For 5 weeks 4 times per day during the intervention phase (between week 5 and week 10)

Study Arms (2)

Slow paced breathing (SPB)

ACTIVE COMPARATOR

The participants will receive a 5-week training, starting with one visit to explain the procedure and determine the individual resonance frequency (for reasons of comparison). Afterwards, participants are instructed to practice at home, using the Pebbles. The breathing frequency of the Pebbles will be set at 6 breaths/minute (3-1-4-2) (slow-paced breathing) and participants are instructed to practice 4x5 minutes a day. In week 2 and week 3, follow-up sessions will be scheduled with each participant (in line with the protocol for the HRV-BF group). Similar to the HRV-BF group, the participants will be asked to rate the level of comfort during the training via a secure web-based application (m-path, KU Leuven) and compliance and physiological data will be captured with the Pebbles. The device used to support the home-based training.

Device: Guided breathing exercise - SPB

Heart rate variability biofeedback (HRV-BF)

ACTIVE COMPARATOR

The participants will follow a fixed scheme: consisting of 3 supervised sessions (30 minutes) combined with home-practice on the other days (20 minutes, 4x5 minutes/day), followed by a training period of 2 weeks, without supervised sessions. In the first session, the personal resonance frequency of the participant will be determined. The resonance frequency refers to a breathing frequency between 4.5 and 7 breaths per minute at which heart rate and the breathing pattern are in phase, also known as Respiratory Sinus Arrhythmia. This introductory session is followed by two supervised training session in week 2 and 3. The participants will be asked to rate the level of comfort during the training via a secure web-based application (m-path, KU Leuven) and compliance and physiological data will be captured with the Pebbles. The device used to support the home-based training.

Device: Guided breathing exercise - HRV-BF

Interventions

Guided breathing exercise - SPB DEVICE

Guided breathing exercises are performed at a fixed pace of 6 breaths per minute (SPB) .

Slow paced breathing (SPB)

Guided breathing exercise - HRV-BF DEVICE

Guided breathing exercises are performed at each participant's individually determined resonance frequency, which typically falls between 4.5 and 7 breaths per minute (HRV-BF).

Heart rate variability biofeedback (HRV-BF)

Eligibility Criteria

• Age: 16 Years - 25 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64)

You may qualify if:

• For participants ≥18 years a voluntary written informed consent and for participants \< 18 years a written informed consent from the parents or their legally authorized representative and an informed assent of the participant has been obtained prior to any screening procedures
• Male or Female (biological)
• Between 16 and 25 years old
• Diagnosis of autism as described in the DSM-IV/DSM-5(-TR)

You may not qualify if:

• Participant has a history of congenital heart diseases, diagnosed cardiovascular abnormalities or somatic diseases conditions that may interfere with the main outcome measure HRV or with the safe practice of breathing exercises (e.g., uncontrolled epilepsy, severe respiratory illness)
• Presence of contra-indications for participating (intervention and/or assessment): acute agitation and/or severe psychiatric symptoms (psychosis, mania or major depression) and/or active substance use.
• The presence of an intellectual disability, defined as an intelligence quotient \< 70, as described in the DSM-IV/DSM-V.
• Insufficient knowledge of Dutch language in order to follow instructions and fill out questionnaires.
• Female who is pregnant.
• Participation in another interventional study, with or without an investigational medicinal product (IMP) or device (IMD).
• The use of medication known to affect cardiac modulation (excluding hormonal contraceptives).
• Hearing- or vision impairment that cannot be corrected to normal functioning.

Sponsors & Collaborators

• Universitaire Ziekenhuizen KU Leuven: lead

Study Sites (2)

KU Leuven

Leuven, Vlaams Brabant, 3000, Belgium

RECRUITING

UPC Z.Org

Leuven, Belgium

NOT YET RECRUITING

MeSH Terms

Conditions

Autistic Disorder; Autism Spectrum Disorder

Condition Hierarchy (Ancestors)

Child Development Disorders, Pervasive; Neurodevelopmental Disorders; Mental Disorders

Study Officials

• Tine Van Damme, Prof. dr.

  KU Leuven

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Esther Meers

CONTACT

+32 479976950; esther.meers@kuleuven.be

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Masking Details: The researcher plays an active role during the intervention, and participants will be informed about the different interventions provided in both groups.
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: The study begins with an assessment at T0, followed by a five-week baseline period. The assessment consist of a physiological measurement and three mental health questionnaires. During the baseline period, all participants will wear an accelerometer to monitor their movement behaviors. The accelerometer will be wrist worn for 7 consecutive days. After this baseline period, participants will be randomly assigned to one of two intervention groups (HRV- biofeedback or slow-paced breathing) and the second assessment will take place at T1. The following intervention period lasts five weeks. During this period, all participants will receive 3 supervised sessions with the researcher, combined with home-based practice. After the intervention period the third assessment will take place at T2. Following the intervention, there will be a five-week no-intervention period for all participants. After this, a follow-up assessment will take place at T3.

Study Record Dates

• First Submitted: September 19, 2025
• First Posted: November 20, 2025
• Study Start: November 30, 2025
• Primary Completion (Estimated): April 1, 2028
• Study Completion (Estimated): April 1, 2028
• Last Updated: April 29, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ICF, ANALYTIC CODE
• Time Frame: IPD will be made available beginning 6 months after publication of the primary results and will remain available for at least 10 years.
• Access Criteria: De-identified individual participant data will be shared with qualified researchers for non-commercial scientific purposes. Requests must include a short proposal describing the planned analyses. Access will be granted following review by the principal investigator. Approved researchers will be required to sign a data use agreement prior to receiving access through the KU Leuven Research Data Repository.

Locations

BE (2)